atn438 lte ran troubleshooting (1of2) ericsson v1.9c ce att 926p

4G

LT

E

VoLT

E

LTE

-AD

VAN

CE

D

IMS

TD

-LTE

HS

PA+

S

MA

LL C

ELL

S

DA

S

SD

N

NFV

IP

CO

NVE

RG

EN

CE

IP

v6

CLO

UD

M

2M

TE

CH

NO

LOG

Y TR

EN

DS

ATT_926p

LTE RAN TROUBLESHOOTING

WORKSHOP FOR UMTS OPERATORS (1 OF 2)

WORKBOOK FOR ERICSSON MARKETSCUSTOMIZED COURSE FOR AT&TContains AT&T Confidential Information

This eBook may contain AT&T Proprietary and Confidential Information, restricted to the use of a single authorized AT&T staff member. Do not distribute in electronic or print form.

LTE RAN Troubleshooting Workshop (1 of 2) Workbook for Ericsson Markets

Award Solutions, Inc. www.awardsolutions.com +1-972-664-0727

This eBook may contain AT&T Proprietary and Confidential Information, restricted to the use of a single authorized AT&T staff member. Do not distribute in electronic or print form.

© 2014 Award Solutions, Inc. All Rights Reserved. This course book and the material and information contained in it are owned by Award Solutions, Inc. (“Award Solutions”) and Award Solutions reserves for itself and successors and assigns all right, title and interest in and to the content (except the AT&T Content, defined below), Award Solutions’ logos and other trademarks, including all copyrights, authorship rights, moral rights, publication and distribution rights, trademarks and other intellectual property rights. Certain pages of this course book also contain in certain slides and/or narrative some information provided by AT&T (“AT&T Content”) under special license and this course book or the slide or narrative that contains AT&T Content indicate that it contains AT&T confidential information. Award Solutions maintains a description of said AT&T confidential information. AT&T reserves for itself and successors and assigns all right, title and interest in and to the AT&T Content and AT&T’s logos and trademarks, including all copyrights, authorship rights, moral rights, trademarks and other intellectual property rights. The inclusion of AT&T Content in this course book does not create any joint authorship rights in this course book or the subject matter course between Award Solutions and AT&T and does not grant to AT&T or any user any license or other rights in the contents of the course book or course, except as may be expressly set forth in a duly executed written agreement between Award Solutions and AT&T. This course book shall not be modified, reproduced, disseminated or transmitted by or in any medium, form or means, electronic or mechanical, including photocopying, recording or any information retrieval system, in whole or in part, without Award Solutions, Inc.’s express, prior written consent signed by an authorized officer whose authority is evidenced by a duly signed corporate resolution. This course book was designed for use as a student guide with the subject matter course taught by Award Solutions’ authorized employees and contractors. It was not designed to be a standalone textbook. Award Solutions makes no representations or warranties and disclaims all implied warranties with respect to the information contained herein or products derived from use of such information and Award Solutions undertakes no obligation to update or otherwise modify the information or to notify AT&T or any user of any update or obsolescence. To the extent permitted by applicable law, Award Solutions’ total liability in connection with the course and/or course material is the amount actually received by Award from the purchaser/user for the purchase or license of the course and course material. This course book is not made for publication or distribution in the public domain and shall not be published or placed in the public domain, in whole or in part, without Award Solutions, Inc.’s express, prior written consent signed by an authorized officer whose authority is evidenced by a duly signed corporate resolution.

2100 Lakeside Blvd., Suite 300 Richardson, TX 75082 Phone: +1.972.664.0727 Fax: +1.972.664.0729 If you have any questions, concerns or comments regarding this course please write to us at: [email protected]

The 3GPP, LTE and LTE-Advanced logos are the property of Third Generation Partnership Project (3GPP). The 3GPP2 logo is property of Third Generation Partnership Project (3GPP2) and its organization partners. The content of this document is based on 3GPP/LTE and 3GPP2 specifications which are available at www.3gpp.org, and www.3gpp2.org.

http://www.3gpp.org

http://www.3gpp2.org

Award Solutions, Inc. www.awardsolutions.com +1.972.664.0727 v14.1

About Award Solutions

AWARD SOLUTIONS, INC. has over 16 years of training excellence in advanced wireless, IP, and network transformation technologies. Our products and services provide our customers with innovative, flexible, and cost-effective solutions that help rapidly boost workforce productivity to more quickly meet market demands.

Our areas of expertise include:

•4G •DAS •LTE •SDN •VoLTE •NFV •LTE-Advanced •IPConvergence •IMS •IPv6 •TD-LTE •Cloud •HSPA+ •M2M •SmallCells •TechnologyTrends

The level of technical depth in our training programs gives students unique benefits that they can apply immediately. We offer a range of courses appropriate for audiences needing a high-level overview, engineers looking for technical details as well as sales and marketing teams needing a different point of view.

Our Subject Matter Experts (SMEs) and consultants are best-in-class, having achieved substantial industry experience in areas such as product definition and development, network deployment, and network and systems engineering. We strive to help our students and customers “become an expert”.

Award Solutions constantly keeps a finger on the pulse of the industry, always researching new technologies, and updating our curriculums to stay on the cutting edge.

Whether you are a training manager responsible for a large organization, or a team lead responsible for enhancing your team’s skills, Award Solutions can meet your technology training needs.

We offer a multitude of delivery methods and services:

ON-SITETRAINING: Our Subject Matter Experts travel to your facility to engage the students in an interactive learning experience. This is a great option for teams with 12 or more people.

VIRTUALTRAINING: Award Solutions embraces different learning styles and preferences. Our virtual trainings are conducted by our Subject Matter Experts in real-time. This is a great option for teams geographically dispersed.

PUBLICTRAININGEVENTS: Award Solutions hosts a subset of our courses in our office and in conjunction with Industry events. This expert-led sessions are ideal for individuals and small groups. Visit our website at for the latest schedule.

SELF-PACEDeLEARNING: An engaging, cost-effective solution, allowing individuals to take training online at their own pace when their schedule permits.

CERTIFICATIONS: Becoming an Award Certified Expert (A.C.E.) is the best way to for a student to demonstrate expertise, prove their ability to use real-world industry tools, and validate that they have the required knowledge to implement and/or run a successful network.

If you are interested in or have any questions regarding Award Solutions training or services, please visit Award’s website at www.awardsolutions.com or contact us at+1-972-664-0727 ext. 306.

OURPROMISETo continually demonstrate our core values: Integrity, Expertise, Flexibility, Teamwork and Excellent Return on Investment.


Instructor Led Training

EmergingTrendsWi-Fi Technical Overview ..................................................2 daysSmall Cell Essentials .......................................................... 1 daySmall Cell Technical Overview ..........................................2 daysDAS Technical Overview ....................................................2 days

* New Course

WirelessLandscapeExploring Wireless Landscape, IP Convergence, and 4G ...2 daysExploring Wireless Technologies and Networks .................5 daysFundamentals of RF Engineering .....................................2 daysExploring GSM/EGPRS/UMTS/HSPA/HSPA+ ..................5 daysWireless and 3G/4G Basics .............................................. 1 day

UMTS/HSPA+Exploring UMTS (WCDMA) ................................................2 daysMastering UMTS Radio Protocols and Signaling ..................4 daysMastering HSPA Protocols and Signaling ........................3 daysHSPA+ Protocols and Signaling (R7, R8 & R9) .................2 daysUMTS/HSPA/HSPA+ Air Interface ....................................3 daysUMTS/HSPA+ RF Optimization Workshop .......................4 days

TechnologyforBusinessTechnology Trends for Business .......................................2 daysWireless Foundations for Business................................... 1 dayIP Convergence for Sales and Marketing ........................3 daysLTE Services for Enterprise Customers ............................. 1 dayCloud Computing Essentials for Business ........................ 1 dayThe M2M Ecosystem.......................................................... 1 dayUnified Communications and Collaboration .................. 0.5 dayThe World of App Development ......................................... 1 dayThe World of Enterprise .................................................. 0.5 dayThe Mobile Enterprise ........................................................ 1 dayEnterprise Data Networks.................................................. 1 dayData Savvy 101: Data, IP, and the Internet ...................... 1 dayData Savvy 102: Data, IP, and the Enterprise .................. 1 day

*

***

IPConvergence&IMSIP Convergence Essentials ................................................ 1 dayEthernet Backhaul Essentials ........................................... 1 dayExploring IPv6 ..................................................................... 1 dayExploring MPLS .................................................................2 daysExploring IMS (R8) ............................................................3 daysExploring SIP, VoIP and IP Convergence with IMS ..................4 daysExploring TCP/IP Protocols ...............................................2 daysExploring Ethernet Backhaul ............................................2 daysVoice and Video over IP Protocols and Technologies ..................2 daysExploring IP Routing and Ethernet Bridging ....................2 daysEthernet Backhaul Planning .............................................3 daysSIP and Diameter for IMS/VoLTE .....................................2 days

*

4GLTELTE Essentials..................................................................... 1 dayLTE-Advanced Essentials ................................................... 1 dayLTE RAN Performance Essentials ...................................... 1 dayVoLTE Essentials ................................................................ 1 dayLTE and VoLTE Essentials for Cell Techs ..........................2 daysLTE Technology Overview ..................................................2 daysLTE-Advanced Technical Overview ...................................2 daysExploring IPv6 for LTE Networks .......................................2 daysVoLTE and IMS in LTE-EPC Networks ...............................3 daysPolicy and Charging Control in LTE Networks ..................2 daysExploring IMS/VoLTE Networks ........................................2 daysMastering LTE Air Interface ..............................................2 daysMastering TD-LTE Air Interface .........................................2 daysLTE Protocols and Signaling .............................................3 daysLTE and GSM/UMTS Interworking ....................................2 daysLTE-EPC Networks and Signaling .....................................3 daysVoLTE Signaling and Operations: RAN/UE Perspective .........4 daysLTE RF Planning and Design Certification Workshop .....5 daysLTE-EPC Capacity Planning Certification Workshop ........4 daysLTE RAN Capacity Planning Certification Workshop .......3 daysLTE RAN Signaling and Operations Certification .............5 daysLTE RF Optimization Certification Workshop (UE Based) ..5 daysSmall Cell and VoLTE RF Planning and Design Certification Workshop .....4 days

**

*

**

****

***

NetworkTransformationBig Data Technology Overview .......................................... 1 dayExploring Cloud Computing Service Models....................2 daysExploring Software-Defined Networking (SDN) and OpenFlow ..2 daysExploring the Service Oriented Architecture (SOA) .........2 daysExploring Infrastructure as a Service (IaaS) ....................2 daysExploring Network Functions Virtualization (NFV) ...........2 days

*

*

*


Self-paced eLearning

EmergingTrendsOverview of OFDM (e) .....................................................2 hoursMultiple Antenna Techniques (e) ...................................3 hoursWi-Fi Overview (e) ............................................................3 hours Small Cell Overview (e) .....................................................1 hour

(e) eLearning Course

4GLTEWelcome to LTE (e) ............................................................1 hourLTE Overview (e) ..............................................................3 hoursLTE SAE Evolved Packet Core (EPC) Overview (e) .........3 hoursLTE Air Interface Signaling Overview (e) ........................3 hoursVoLTE Overview ...............................................................3 hoursOverview of IPv6 for LTE Networks .................................3 hours

IPConvergence&IMSWelcome to IP Networking (e) ........................................3 hoursIP Convergence Overview (e) ..........................................4 hoursOverview of MPLS (e) .................................................. 3.5 hoursOverview of IMS (e) ..................................................... 2.5 hoursVoice and Video over IP (VoIP) Overview (e) ..................3 hoursIP Quality of Service (QoS) (e) ........................................3 hoursSession Initiation Protocol (SIP) (e) ................................2 hoursEthernet Backhaul Overview (e) .....................................3 hoursIP Basics (e) .......................................................................1 hourIP Routing (e) .....................................................................1 hourQoS in IP Networks (e) ......................................................1 hourTCP and Transport Layer Protocols (e) .............................1 hourEthernet Basics (e) ............................................................1 hourEthernet VLANs (e) ............................................................1 hourEthernet Bridging (e) .........................................................1 hourInterconnecting IP Networks (e) .......................................1 hourWelcome to IPv6 (e) ..........................................................1 hour

UMTS/HSPA+Welcome to UMTS (e).................................................. 1.5 hoursOverview of UMTS (e) ......................................................2 hoursUMTS/WCDMA Air Interface Fundamentals (e) ............3 hoursUMTS Signaling (e) ..........................................................1 hoursUMTS Mobility (e) ............................................................1 hoursHSDPA (R5) (e) ................................................................3 hoursHSUPA (R6) (e) ............................................................ 2.5 hoursHSPA+ Overview (R7) (e) ................................................4 hours

WirelessLandscapeWelcome to Wireless Networks (e) ..................................1 hourWelcome to GSM/GPRS (e) ........................................ 1.5 hours1xEV-DO Networks (Rev 0) (e) ........................................3 hours1xEV-DO Networks (Rev A) (e) ........................................3 hoursOverview of 3G Wireless Networks (e) ....................... 1.5 hoursOverview of WiMAX (e) ....................................................3 hours

*

Table of Contents

ATT_926p Version 1.9c i

Chapter 1

Scope of the Document .................................................................................................................................. 1

Chapter 2

LTE Key Performance Indicators (KPIs) Exercises ........................................................................................ 3

Chapter 3

LTE Coverage Analysis and Exercises .......................................................................................................... 11

Chapter 4

Accessibility KPI Analysis ............................................................................................................................. 19

Chapter 5

Intra-LTE Handover Analysis ......................................................................................................................... 57

Chapter 6

Inter-RAT Mobility ........................................................................................................................................105

Additional Material

Perforated Tear-outs ...................................................................................................................................131

1 | Scope of the Document

1 Scope of the Document This document contains LTE-Uu and network logs collected from the AT&T LTE network. The information

contained is AT&T Proprietary and Confidential and should be treated as per guidelines established by

AT&T for such material.

The message logs have been separated into sections to facilitate discussions during the session.

Relevant snapshots of information from technical specifications have been included. The participant is

expected to complete each section and make note of their observations and discussions in class.

1.1 Convention (AT&T-Provided Proprietary Information)

1.1.1.1 AT&T-Provided Proprietary Information

AT&T-Provided Proprietary Information

Table Data Table Data Table Data Table Data

Table Data Table Data Table Data Table Data

1.2 Convention (Log Messages)

1.2.1 Log Message Capture... (Message Name)

Reference: which market\what scenario-log file 1 This is a log message collected at the UE in your network 2 This is a log message ... 3 This is a log message 4

1.3 Convention (from Specifications)

1.3.1 Specification Definition of a Message... (Message Name)

Reference: abc 5 This is a message snapshot from Specifications 6 This is a message snapshot ... 7 This is a message snapshot 8

1.4 Convention (from Specifications)

1.4.1 Specification Definition of an Information Element Within a Message... (IE Name)

Reference: abc This is a IE snapshot from Specifications 9 This is a IE snapshot ... 10 This is a IE snapshot 11 Specification definition of information... (message parms/IE/other information) 12

Reference: xyz

PRACH Configuration Index

Preamble Format

System frame number

Subframe number

PRACH Configuration Index

Preamble Format

System frame number

Subframe number

0 0 Even 1 32 2 Even 1

... ... ... ... ... ... ... ...

1

1 | Scope of the Document

1.5 Convention (Exercise)

1.5.1 Questions and Space for Answers that Should be Completed

[1] This is question one of the workbook. Enter your name and email address. _____________

___________________________________________________________________________________________________

2

2 | LTE Key Performance Indicators (KPIs) Exercises

2 LTE Key Performance Indicators (KPIs) Exercises

2.1 Mapping Ericsson Counters to AT&T KPIs

2.1.1 Accessibility KPI

Figure 1: Components of Accessibility KPI

Figure 2: AT&T-Defined Accessibility KPI

3


2.1.1.1 Counter Definitions

The following vendor counters are pegged at the cell level. Vendor Counter Name Counter Description

pmRrcConnEstabAtt Pegged upon reception of an RRC Connection Request message.

pmRrcConnEstabSucc Pegged upon reception of an RRC Connection Setup Complete message.

pmRrcConnEstabAttReatt Pegged upon the reception of an RRC Connection Request while an RRC Connection is

already on going for that S-TMSI.

pmS1SigConnEstabAtt This measurement provides the number of S1 Signalling connection establishment

attempts for any establishment cause. Pegged at transmission of Initial UE message.

pmS1SigConnEstabSucc The total number of successful S1 signalling connection establishments. Pegged at the

first occurrence of reception of any message on this S1 logical connection.

PmErabEstabAttInit The total number of initial E-RAB Establishment attempts. Initial E-RABs are all E-RABs

present in the S1 message Initial Context Setup Request. Pegged for each E-RAB

received in the S1 message Initial Context Setup Request.

pmErabEstabSuccInit The total number of successful initial E-RAB Establishments. Initial E-RABs are all E-RABs

present in the S1 message Initial Context Setup Request. Pegged for each initial E-RAB

that is successfully established.

pmErabEstabAttAdded The total number of added E-RAB Establishment attempts. Added E-RABs are all E-RABs

present in S1 message E-RAB Setup Request. Pegged for each bearer received in the S1

message E-RAB Setup Request.

pmErabEstabSuccAdded The total number of successfully added E-RABs. Added E-RABs are all E-RABs present in

S1 message E-RAB Setup Request. Pegged for each added bearer that is successfully

established.

2.1.2 E-RAB Retainability KPI

Figure 3: AT&T-Defined E-RAB Retainability Success KPI

4




pmErabRelNormalEnb The total number of normal E-RAB Releases triggered by RBS. The counter is pegged

regardless of whether data was or was not lost in UL/DL buffers. It is pegged at the

reception of the S1 message E-RAB Release Command or the UE Context Release

Command when the internal cause codes are considered normal (user inactivity, inter-

RAT redirection, CS Fallback-triggered) and when the RBS initiated the release.

pmErabRelAbnormalEnbAct The total number of abnormal E-RAB Releases initiated by the RBS and with data in

either the UL or DL buffer (i.e., active). If there was data in the buffer at the time of

release, then it is pegged at the reception of the S1 message E-RAB Release Command

or UE Context Release Command, when internal cause codes are considered abnormal

(Radio Connection with UE is lost; handover failure for the UE; non-admitted E-RABs by

target cell at successful handover for the UE; UE pre-emption), and when the RBS

initiated the release. It can also be stepped at the transmission of the E-RAB Release

Indication, the UE Context Release Request or a Reset message by the RBS, or when a

cell owned by that RBS is disabled (and which leads to internal RBS UE Context

Release).

pmErabRelAbnormalMmeAct The total number of E-RAB Releases initiated by the MME considered as Abnormal. The

counter is stepped if there was data in either the UL or DL buffer (i.e., active). Pegged

at reception of the S1 message E-RAB Release Command or UE Context Release and

when there was data in either the UL or DL buffer (i.e., active). The release must also

have been MME-initiated.

2.1.3 Throughput KPI

Figure 4: AT&T DL Throughput KPI

Figure 5: AT&T UL Throughput KPI

5




pmPdcpVolDlDrb The total volume (PDCP SDU) on Data Radio Bearers that has been transferred

(acknowledged by the UE) in the downlink direction (measured in units of kbits).

pmPdcpVolDlDrbLastTTI The total volume (PDCP SDU) on Data Radio Bearers that has been transferred

(acknowledged by the UE) in the downlink direction in the last TTI when a buffer is

emptied (measured in units of kbits).

pmUeThpTimeDl Amount of time required to transmit DL data in buffer, not including the last TTI when the

buffer was empty (measured in msec).

pmUeThpVolUl The UL DRB volume used for UL UE throughput. It is composed of the MAC SDU volume

received on the air interface, excluding both the volume received in the first four data

receptions of a UL buffer transfer and the TTI emptying the UL buffer (measured in units

of kbits).

pmUeThpTimeUl The UL volume transfer time used for UL UE throughput. It is composed of time periods

from the fifth MAC SDU’s data reception of a UL buffer transfer on the air interface until

the buffer is emptied, excluding the TTI emptying the buffer (measured in msec).

2.1.4 Intra-Frequency Mobility KPI

Figure 6: AT&T-Defined Intra-Frequency Handover Success Rate KPI

6



The following vendor counters are part of the EUtranCellRelation Managed Object and are pegged at the cell

relation (i.e., neighbor) level. Vendor Counter Name Counter Description

pmHoPrepAttLteIntraF Pegged during the preparation phase of an intra-frequency handover when the source

eNodeB sends either an X2 Handover Request message or a S1 Handover Required

message.

pmHoPrepSuccLteIntraF Pegged during the preparation phase of an intra-frequency handover when the source

eNodeB receives either an X2 Handover Request Ack message or a S1 Handover

Command message, indicating the target eNodeB has reserved resources for the UE’s

pending handover.

pmHoExeAttLteIntraF Pegged during the execution phase of an intra-frequency handover when the source

eNodeB sends a RRC Connection Reconfiguration message to the UE which includes

mobility control information.

pmHoExeSuccLteIntraF Pegged during the execution phase of an intra-frequency handover when the source

eNodeB receives either an X2 UE Context Release message or a S1 UE Context Release

Command message, indicating the UE has successfully performed a handover to the

target eNodeB.

2.1.5 Inter-Frequency Mobility KPI

Figure 7: AT&T-Defined Inter-Frequency Handover Success Rate KPI




pmHoPrepAttLteInterF Pegged during the preparation phase of an inter-frequency handover when the source

eNodeB sends either an X2 Handover Request message or a S1 Handover Required

message.

pmHoPrepSuccLteInterF Pegged during the preparation phase of an inter-frequency handover when the source

eNodeB receives either an X2 Handover Request Ack message or a S1 Handover

Command message, indicating the target eNodeB has reserved resources for the UE’s

pending handover.

pmHoExeAttLteInterF Pegged during the execution phase of an inter-frequency handover when the source

eNodeB sends a RRC Connection Reconfiguration message to the UE which includes


pmHoExeSuccLteInterF Pegged during the execution phase of an inter-frequency handover when the source

eNodeB receives either an X2 UE Context Release message or a S1 UE Context Release

Command message, indicating the UE has successfully performed a handover to the

target eNodeB.

7


2.1.6 IRAT Redirect % KPI

Figure 8: AT&T-Defined IRAT Redirect % KPI



pmUeCtxtRelSCGsm The number of Session Continuity RRC Connection Releases with a redirect to GERAN.

Pegged upon reception of a S1 UE Context Release Command as a result of an IRAT to

the GSM.

pmUeCtxtRelSCWcdma The number of Session Continuity RRC Connection Releases with a redirect to UTRA FDD.

Pegged upon reception of a S1 UE Context Release Command as a result of an IRAT to

UMTS.

pmUeCtxtEstabSucc The total number of Initial Context Setup Establishment successes. Pegged upon

transmission Initial Context Setup Response message.

2.1.7 % Time not on LTE (TnoL)

The % Time not on LTE measurement KPI is designed to measure the network’s ability to provide LTE service to

LTE-capable devices. This KPI is calculated seperately for data-only devices and CSFB-capable devices. The

measurements used in the calculation of this KPI are derived from cell trace records (CDRs).

The measurement is made only within the LTE-launched service area (LTE polygon). Usage of LTE devices

outside the LTE service area is not included.

Because customers may use LTE-capable devices without having upgraded to LTE rate plans, the metric is

based on a “white list” of customers and their devices that have, at some point, successfully accessed the LTE

network. Devices that are unable to access the LTE network because of service provisioning issues, rate plan

incompatibility, etc. are not included in the metric.

8


Figure 9: AT&T-Defined % TnoL KPI

2.1.8 CS Fallback % KPI

Figure 10: AT&T-Defined CSFB % KPI



pmUeCtxtRelCsfbWcdma Pegged upon the reception of a S1 UE Context Release Command as a result of a CSFB

to UMTS.

pmUeCtxtRelCsfbWcdmaEm Pegged upon the reception of a S1 UE Context Release Command as a result of a CSFB

to UMTS due to an emergency call.

pmUeCtxtEstabSucc Pegged upon transmission Initial Context Setup Response message.

9

3 | LTE Coverage Analysis and Exercises

3 LTE Coverage Analysis and Exercises

3.1 Reference Signal (RSRP and RSRQ) Formulas (from Specifications)

3.1.1 Reference Signal Received Power (RSRP)

Reference: (3GPP TS 36.214 Section 5.1.1)

Definition Reference Signal Received Power (RSRP) is defined as the linear average over the power contributions (in [W]) of the resource elements that carry cell-specific reference signals within the considered measurement frequency bandwidth. For RSRP determination, the cell-specific reference signals R0 according TS 36.211 [3] are used. If the UE can reliably detect that R1 is available, it may use R1 in addition to R0 to determine RSRP. If receiver diversity is in use by the UE, the reported value should not be lower than the corresponding RSRP of any of the individual diversity branches.

Applicable for RRC_IDLE intra-frequency RRC_IDLE inter-frequency RRC_CONNECTED intra-frequency RRC_CONNECTED inter-frequency

Note 1: The number of resource elements within the considered measurement frequency bandwidth and within

the measurement period that are used by the UE to determine RSRP is left up to the UE implementation with

the limitation that corresponding measurement accuracy requirements have to be fulfilled.

Note 2: The power per resource element is determined from the energy received during the useful part of the

symbol, excluding the CP.

3.1.2 Reference Signal Received Quality (RSRQ)


Definition Reference Signal Received Quality (RSRQ) is defined as the ratio N×RSRP/(E-UTRA carrier RSSI), where N is the number of RBs of the E-UTRA carrier RSSI measurement bandwidth. The measurements in the numerator and denominator shall be made over the same set of resource blocks. E-UTRA Carrier Received Signal Strength Indicator (RSSI), comprises the linear average of the total received power (in [W]) observed only in OFDM symbols containing reference symbols for antenna port 0 in the measurement bandwidth, over N number of resource blocks by the UE from all sources including co-channel serving and non-serving cells, adjacent channel interference, thermal noise, etc. If receiver diversity is in use by the UE, the reported value shall not be lower than the corresponding RSRQ of any of the individual diversity branches.

Applicable for RRC_CONNECTED intra-frequency RRC_CONNECTED inter-frequency

3.1.3 DL Reference Signal TX power


Definition Downlink reference signal transmit power is determined for a considered cell as the linear average over the power contributions (in [W]) of the resource elements that carry cell-specific reference signals which are transmitted by the eNodeB within its operating system bandwidth. For DL RS TX power determination, the cell-specific reference signals R0 and if available R1 according TS 36.211 [3] can be used. The reference point for the DL RS TX power measurement is the TX antenna connector.

11


3.1.4 RSRP Measurement Report Mapping


The reporting range of RSRP is defined from -140 dBm to -44 dBm with 1 dB resolution.

Reported value Measured quantity value Unit

RSRP_00 RSRP -140 dBm

RSRP_01 -140 RSRP < -139 dBm

RSRP_02 -139 RSRP < -138 dBm

… … …

RSRP_95 -46 RSRP < -45 dBm

RSRP_96 -45 RSRP < -44 dBm

RSRP_97 -44 RSRP dBm

RSRP [dBm] = Reported Value - 140

3.1.5 RSRQ Measurement Report Mapping


The reporting range of RSRQ is defined from -19.5 dB to -3 dB with 0.5 dB resolution.


RSRQ_00 RSRQ -19.5 dB

RSRQ_01 -19.5 RSRQ < -19 dB

RSRQ_02 -19 RSRQ < -18.5 dB

… … …

RSRQ_32 -4 RSRQ < -3.5 dB

RSRQ_33 -3.5 RSRQ < -3 dB

RSRQ_34 -3 RSRQ dB

RSRQ [dB] = (Reported Value/2) - 20

12


3.2 RF Coverage Exercises

3.2.1 Dominant RSRP

Figure 1: Best Server RSRP Coverage Plot

[1] Describe how the Best Server RSRP Coverage Plot could be used to identify coverage issues.

13


3.2.2 Dominant PCI Plot

Figure 2: Best Server PCI Plot

[2] Describe how the Dominant PCI Plot could be used to identify coverage issues.

14


3.2.3 Dominant RS CINR Plot

Figure 3: Dominant RS CINR Plot

[3] Describe how the Best Server RS CINR could be used to identify coverage issues.

15


3.2.4 RSRP per PCI Plot

Figure 4: Per PCI RSRP Plot

[4] Describe how the Per Cell Coverage Plot could be used to identify coverage issues.

16


3.2.5 CINR per PCI Plot

Figure 5: Per PCI CINR Plot

[5] Describe how the Per Cell Coverage Plot could be used to identify coverage issues.

17

4 | Accessibility KPI Analysis

4 Accessibility KPI Analysis This chapter will investigate the steps required to set up an LTE call. This will include the random access

procedure as well as the RRC, S1 Signaling Connection, and Default Bearer establishment.

Figure 1: Components of Accessibility KPI

19


4.1 Random Access Procedures

This section will give an overview of the Random Access procedure.

Figure 2: Random Access Algorithm

4.1.1 Broadcasting Random Access Parameters

The first stage of system access is the broadcasting of the cell’s Random Access parameters to the UE. This is

achieved by means of System Information Blocks (SIBs). SIB 2 transmits cell-specific parameters for Random

Access.

Figure 3: Broadcasting Random Access Parameters

20


4.1.2 System Information Block 2 (UE Log Message)

Reference: SCL08-CL38_East1/0808_01.log Time : 23:19:15.161 1 Vendor Header 2 Length : 57 3 Log Code (Hex) : 0xB0C0 4 HW Timestamp : (15554365.00 ms) 04:19:14.365 5 1.25 ms fraction : 0.00 6 CFN : 148 7 1.25 ms counter : 822816923492 8 RRC Signaling Header 9 Log Packet Version : 1 10 RRC Release Number : 8.7.0 11 Radio Bearer Id : 0 12 Physical Cell Id : 273 13 E-ARFCN : 5815 14 System Frame Number 15 System frame number : N/A 16 Sub frame number : N/A 17 Message Type : BcchSchDownlink 18 Message Length : 32 19 criticalExtensions : systemInformation-r8 20 systemInformation-r8 21 sib-TypeAndInfo : 22 [0 ] : 23 noName : choiceInSequence 24 choiceInSequence : sib2 25 sib2 26 radioResourceConfigCommon 27 rach-ConfigCommon 28 numberOfRA-Preambles : n64 29 powerRampingStep : dB4 30 preambleInitialReceivedTargetPower : dBm-110 31 preambleTransMax : n10 32 ra-ResponseWindowSize : sf4 33 mac-ContentionResolutionTimer : sf64 34 maxHARQ-Msg3Tx : 4 35 bcch-Config 36 modificationPeriodCoeff : n2 37 pcch-Config 38 defaultPagingCycle : rf128 39 nB : oneT 40 prach-Config 41 rootSequenceIndex : 70 42 prach-ConfigInfo 43 prach-ConfigIndex : 5 44 highSpeedFlag : False 45 zeroCorrelationZoneConfig : 12 46 prach-FreqOffset : 2 47 pdsch-ConfigCommon 48 referenceSignalPower : 23 49 p-b : 1 50 pusch-ConfigCommon 51 n-SB : 1 52 hoppingMode : interSubFrame 53 pusch-HoppingOffset : 0 54 enable64QAM : False 55 ul-ReferenceSignalsPUSCH 56 groupHoppingEnabled : True 57 groupAssignmentPUSCH : 0 58 sequenceHoppingEnabled : False 59 cyclicShift : 0 60 pucch-ConfigCommon 61

21


deltaPUCCH-Shift : ds1 1 nRB-CQI : 1 2 nCS-AN : 0 3 n1PUCCH-AN : 16 4 soundingRS-UL-ConfigCommon 5 SoundingRS-UL-ConfigCommon : setup 6 srs-BandwidthConfig : bw2 7 srs-SubframeConfig : sc3 8 ackNackSRS-SimultaneousTransmission : True 9 uplinkPowerControlCommon 10 p0-NominalPUSCH : -106 11 alpha : al1 12 p0-NominalPUCCH : -120 13 deltaFList-PUCCH 14 deltaF-PUCCH-Format1 : deltaF0 15 deltaF-PUCCH-Format1b : deltaF3 16 deltaF-PUCCH-Format2 : deltaF0 17 deltaF-PUCCH-Format2a : deltaF0 18 deltaF-PUCCH-Format2b : deltaF0 19 deltaPreambleMsg3 : 6 20 ul-CyclicPrefixLength : len1 21 ue-TimersAndConstants 22 t300 : ms1000 23 t301 : ms400 24 t310 : ms2000 25 n310 : n20 26 t311 : ms3000 27 n311 : n1 28 additionalSpectrumEmission : 1 29 timeAlignmentTimerCommon : infinity 30 [1 ] : 31 noName : choiceInSequence 32 choiceInSequence : sib3 33 sib3 34 q-Hyst : dB4 35 s-NonIntraSearch : 3 36 threshServingLow : 3 37 cellReselectionPriority : 5 38 q-RxLevMin : -61 39 p-Max : 23 40 s-IntraSearch : 31 41 allowedMeasBandwidth : mbw25 42 presenceAntennaPort1 : True 43 neighCellConfig 44 Binary string (Bin) : 01 45 [0 ] : 0 46 [1 ] : 1 47 t-ReselectionEUTRA : 2 48

22


4.1.3 SystemInformationBlockType2 (from Specifications)

Reference: (3GPP TS 36.331 Section 6.3.1) -- ASN1START 1 2 SystemInformationBlockType2 ::= SEQUENCE 3 ac-BarringInfo SEQUENCE 4 ac-BarringForEmergency BOOLEAN, 5 ac-BarringForMO-Signalling AC-BarringConfig OPTIONAL, -- Need 6 OP 7 ac-BarringForMO-Data AC-BarringConfig OPTIONAL -- Need 8 OP 9 OPTIONAL, -- Need 10 OP 11 radioResourceConfigCommon RadioResourceConfigCommonSIB, 12 ue-TimersAndConstants UE-TimersAndConstants, 13 freqInfo SEQUENCE 14 ul-CarrierFreq ARFCN-ValueEUTRA OPTIONAL, -- Need 15 OP 16 ul-Bandwidth ENUMERATED n6, n15, n25, n50, n75, n100 17 OPTIONAL, -- Need 18 OP 19 additionalSpectrumEmission AdditionalSpectrumEmission 20 , 21 mbsfn-SubframeConfigList MBSFN-SubframeConfigList OPTIONAL, -- Need 22 OR 23 timeAlignmentTimerCommon TimeAlignmentTimer, 24 ... 25 26 27 AC-BarringConfig ::= SEQUENCE 28 ac-BarringFactor ENUMERATED 29 p00, p05, p10, p15, p20, p25, p30, p40, 30 p50, p60, p70, p75, p80, p85, p90, p95, 31 ac-BarringTime ENUMERATED s4, s8, s16, s32, s64, s128, s256, s512, 32 ac-BarringForSpecialAC BIT STRING (SIZE(5)) 33 34 35 MBSFN-SubframeConfigList ::= SEQUENCE (SIZE (1..maxMBSFN-Allocations)) OF MBSFN-36 SubframeConfig 37 38 MBSFN-SubframeConfig ::= SEQUENCE 39 radioframeAllocationPeriod ENUMERATED n1, n2, n4, n8, n16, n32, 40 radioframeAllocationOffset INTEGER (0..7), 41 subframeAllocation CHOICE 42 oneFrame BIT STRING (SIZE(6)), 43 fourFrames BIT STRING (SIZE(24)) 44 45 46 -- ASN1STOP 47

23


4.1.4 RadioResourceConfigCommon


The IE RadioResourceConfigCommonSIB and IE RadioResourceConfigCommon are used to specify common

radio resource configurations in the system information and in the mobility control information, respectively,

e.g., the random access parameters and the static Physical Layer parameters. -- ASN1START 1 2 RadioResourceConfigCommonSIB ::= SEQUENCE 3 rach-ConfigCommon RACH-ConfigCommon, 4 bcch-Config BCCH-Config, 5 pcch-Config PCCH-Config, 6 prach-Config PRACH-ConfigSIB, 7 pdsch-ConfigCommon PDSCH-ConfigCommon, 8 pusch-ConfigCommon PUSCH-ConfigCommon, 9 pucch-ConfigCommon PUCCH-ConfigCommon, 10 soundingRS-UL-ConfigCommon SoundingRS-UL-ConfigCommon, 11 uplinkPowerControlCommon UplinkPowerControlCommon, 12 ul-CyclicPrefixLength UL-CyclicPrefixLength, 13 ... 14 15 16 RadioResourceConfigCommon ::= SEQUENCE 17 rach-ConfigCommon RACH-ConfigCommon OPTIONAL, -- Need 18 ON 19 prach-Config PRACH-Config, 20 pdsch-ConfigCommon PDSCH-ConfigCommon OPTIONAL, -- Need 21 ON 22 pusch-ConfigCommon PUSCH-ConfigCommon, 23 phich-Config PHICH-Config OPTIONAL, -- Need 24 ON 25 pucch-ConfigCommon PUCCH-ConfigCommon OPTIONAL, -- Need 26 ON 27 soundingRS-UL-ConfigCommon SoundingRS-UL-ConfigCommon OPTIONAL, -- Need 28 ON 29 uplinkPowerControlCommon UplinkPowerControlCommon OPTIONAL, -- Need 30 ON 31 antennaInfoCommon AntennaInfoCommon OPTIONAL, -- Need ON 32 p-Max P-Max OPTIONAL, -- Need 33 OP 34 tdd-Config TDD-Config OPTIONAL, -- Cond 35 TDD 36 ul-CyclicPrefixLength UL-CyclicPrefixLength, 37 ... 38 39 40 BCCH-Config ::= SEQUENCE 41 modificationPeriodCoeff ENUMERATED n2, n4, n8, n16 42 43 44 PCCH-Config ::= SEQUENCE 45 defaultPagingCycle ENUMERATED 46 rf32, rf64, rf128, rf256, 47 nB ENUMERATED 48 fourT, twoT, oneT, halfT, quarterT, oneEighthT, 49 oneSixteenthT, oneThirtySecondT 50 51 52 UL-CyclicPrefixLength ::= ENUMERATED len1, len2 53

RadioResourceConfigCommon Information Element

24


4.1.5 RACH-ConfigCommon


The IE RACH-ConfigCommon is used to specify the generic random access parameters. -- ASN1START 1 2 RACH-ConfigCommon ::= SEQUENCE 3 preambleInfo SEQUENCE 4 numberOfRA-Preambles ENUMERATED 5 n4, n8, n12, n16 ,n20, n24, n28, 6 n32, n36, n40, n44, n48, n52, n56, 7 n60, n64, 8 preamblesGroupAConfig SEQUENCE 9 sizeOfRA-PreamblesGroupA ENUMERATED 10 n4, n8, n12, n16 ,n20, n24, n28, 11 n32, n36, n40, n44, n48, n52, n56, 12 n60, 13 messageSizeGroupA ENUMERATED b56, b144, b208, b256, 14 messagePowerOffsetGroupB ENUMERATED 15 minusinfinity, dB0, dB5, dB8, dB10, dB12, 16 dB15, dB18, 17 ... 18 OPTIONAL -- Need OP 19 , 20 powerRampingParameters SEQUENCE 21 powerRampingStep ENUMERATED dB0, dB2,dB4, dB6, 22 preambleInitialReceivedTargetPower ENUMERATED 23 dBm-120, dBm-118, dBm-116, dBm-114, dBm-112, 24 dBm-110, dBm-108, dBm-106, dBm-104, dBm-102, 25 dBm-100, dBm-98, dBm-96, dBm-94, 26 dBm-92, dBm-90 27 , 28 ra-SupervisionInfo SEQUENCE 29 preambleTransMax ENUMERATED 30 n3, n4, n5, n6, n7, n8, n10, n20, n50, 31 n100, n200, 32 ra-ResponseWindowSize ENUMERATED 33 sf2, sf3, sf4, sf5, sf6, sf7, 34 sf8, sf10, 35 mac-ContentionResolutionTimer ENUMERATED 36 sf8, sf16, sf24, sf32, sf40, sf48, 37 sf56, sf64 38 , 39 maxHARQ-Msg3Tx INTEGER (1..8), 40 ... 41 42

RACH-ConfigCommon Information Element

25


4.1.6 ZeroCorrelation Configuration Index


NCS

configuration NCS value Unrestricted

set

NCS value Restricted

set 0 0 15

1 13 18

2 15 22

3 18 26

4 22 32

5 26 38

6 32 46

7 38 55

8 46 68

9 59 82

10 76 100

11 93 128

12 119 158

13 167 202

14 279 237

15 419

26


4.1.7 PRACH Configurations

Frame Structure Type 1: RACH Configuration for preamble format 0-3


PRACH Configuration

Index

Preamble Format

System frame

number

Subframe number

PRACH Configuration

Index

Preamble Format

System frame

number

Subframe number

0 0 Even 1 32 2 Even 1 1 0 Even 4 33 2 Even 4 2 0 Even 7 34 2 Even 7 3 0 Any 1 35 2 Any 1 4 0 Any 4 36 2 Any 4 5 0 Any 7 37 2 Any 7 6 0 Any 1, 6 38 2 Any 1, 6 7 0 Any 2 ,7 39 2 Any 2 ,7 8 0 Any 3, 8 40 2 Any 3, 8 9 0 Any 1, 4, 7 41 2 Any 1, 4, 7

10 0 Any 2, 5, 8 42 2 Any 2, 5, 8 11 0 Any 3, 6, 9 43 2 Any 3, 6, 9 12 0 Any 0, 2, 4, 6, 8 44 2 Any 0, 2, 4, 6, 8 13 0 Any 1, 3, 5, 7, 9 45 2 Any 1, 3, 5, 7, 9 14 0 Any 0, 1, 2, 3,

4, 5, 6, 7, 8, 9

46 N/A N/A N/A

15 0 Even 9 47 2 Even 9 16 1 Even 1 48 3 Even 1 17 1 Even 4 49 3 Even 4 18 1 Even 7 50 3 Even 7 19 1 Any 1 51 3 Any 1 20 1 Any 4 52 3 Any 4 21 1 Any 7 53 3 Any 7 22 1 Any 1, 6 54 3 Any 1, 6 23 1 Any 2 ,7 55 3 Any 2 ,7 24 1 Any 3, 8 56 3 Any 3, 8 25 1 Any 1, 4, 7 57 3 Any 1, 4, 7 26 1 Any 2, 5, 8 58 3 Any 2, 5, 8 27 1 Any 3, 6, 9 59 3 Any 3, 6, 9 28 1 Any 0, 2, 4, 6, 8 60 N/A N/A N/A 29 1 Any 1, 3, 5, 7, 9 61 N/A N/A N/A 30 N/A N/A N/A 62 N/A N/A N/A 31 1 Even 9 63 3 Even 9

27


4.1.8 UplinkPowerControl


The IE UplinkPowerControlCommon and IE UplinkPowerControlDedicated are used to specify parameters for

uplink power control in the system information and in the dedicated signaling, respectively.

Parameter: 3_ MsgPREAMBLE see TS 36.213 [23, 5.1.1.1]. Actual value = IE value * 2 [dB].

-- ASN1START 1 2 UplinkPowerControlCommon ::= SEQUENCE 3 p0-NominalPUSCH INTEGER (-126..24), 4 alpha ENUMERATED al0, al04, al05, al06, al07, al08, al09, 5 al1, 6 p0-NominalPUCCH INTEGER (-127..-96), 7 deltaFList-PUCCH DeltaFList-PUCCH, 8 deltaPreambleMsg3 INTEGER (-1..6) 9 10 11 UplinkPowerControlDedicated ::= SEQUENCE 12 p0-UE-PUSCH INTEGER (-8..7), 13 deltaMCS-Enabled ENUMERATED en0, en1, 14 accumulationEnabled BOOLEAN, 15 p0-UE-PUCCH INTEGER (-8..7), 16 pSRS-Offset INTEGER (0..15), 17 filterCoefficient FilterCoefficient DEFAULT fc4 18 19 20 DeltaFList-PUCCH ::= SEQUENCE 21 deltaF-PUCCH-Format1 ENUMERATED deltaF-2, deltaF0, deltaF2, 22 deltaF-PUCCH-Format1b ENUMERATED deltaF1, deltaF3, deltaF5, 23 deltaF-PUCCH-Format2 ENUMERATED deltaF-2, deltaF0, deltaF1, deltaF2, 24 deltaF-PUCCH-Format2a ENUMERATED deltaF-2, deltaF0, deltaF2, 25 deltaF-PUCCH-Format2b ENUMERATED deltaF-2, deltaF0, deltaF2 26 27 -- ASN1STOP 28

UplinkPowerControl Information Elements

The following are configuration parameters related to the RACH procedure.

Vendor Parameter Name Parameter Description

rachRootSequence The first root sequence number for Random Access Channel (RACH) preamble

generation. RACH root sequence is broadcast as a part of system information

distribution and used for preamble detection (Range: 0.. 837).

CellRange Defines the maximum distance from the base station where a connection to a UE can

be setup and/or maintained (Default value: 15 Km).

cfraEnable This parameter controls if Contention Free Random Access (CFRA) shall be enabled or

not. When enabled, a portion of random access preambles should be allocated for

CFRA and CFRA can be used for incoming handovers.

28


4.1.9 Exercises

[1] Using the log file for SIB 2 above (or the SIB2 for the local market provided by the instructor,

Chapter_4_Exercise_1.txt), provide the configured and effective values for the following parameters.

Parameter Name Configured Value Effective Value

a) numberOfRA-Preambles

b) powerRampingStep

c) preambleInitialReceivedTargetPower

d) preambleTransMax

e) rootSequenceIndex

f) zerocorrelationZoneConfig

g) powerRampingStep

h) prach-ConfigIndex

i) referenceSignalPower

j) deltaPreambleMsg3

k) T300

29


[2] Referring to the answers provided above, answer the following questions regarding the Random

Access configuration for this cell.

a) Based on the number of available preambles for this cell, how many preambles are being reserved for:

Contention-Free Random Access?

Contention-Based Random Access?

b) How does the UE determine which specific preambles are allocated for this specific cell?

c) Assume the UE measures a RSRP of -80 dBm. What will the calculated path loss be?

d) Based on this RSRP of -80 dBm, what will the power of the initial preamble be?

e) What will the power of the second preamble be, assuming no RAR is received?

f) What will the power of the initial preamble be if the UE is at the cell-edge and measures a RSRP = QRxLevMin?

30


4.1.10 Random Access Attempt (UE Log Message)

Reference: ATT_Drive_Test.log ML1 Idle Neighbor Cell Measurement Request/Response 1 2 Time : 18:33:02.343 3 Length : 144 4 Log Code (Hex) : 0xB192 5 HW Timestamp : (84781066.25 ms) 23:33:01.066 6 1.25 ms fraction : 0.00 7 CFN : 4 8 1.25 ms counter : 803449584853 9 Version : 1 10 Number of Subpackets : 2 11 Subpackets : 12 [0 ] : 13 Idle Mode Log Subpacket 14 Subpacket ID : 0x1A 15 Subpacket Version : 1 16 Subpacket Size (bytes) : 40 17 Idle Mode Neighbor Cell Measurement Request 18 EARFCN : 5780 19 Number of Cells : 2 20 Number of Rx Antennas : 2 21 Duplexing Mode : Duplex Mode FDD 22 Neighbor Cells : 23 [0 ] : 24 Cell Id : 219 25 Cyclic Prefix Type : CP Mode Normal 26 Number of Tx Antennas : 1 27 TTL : Disabled 28 FTL : Disabled 29 [1 ] : 30 Cell Id : 287 31 Cyclic Prefix Type : CP Mode Normal 32 Number of Tx Antennas : 1 33 TTL : Disabled 34 FTL : Disabled 35 [1 ] : 36 Idle Mode Log Subpacket 37 Subpacket ID : 0x1B 38 Subpacket Version : 1 39 Subpacket Size (bytes) : 88 40 Neighbor Cell Measurement Result 41 EARFCN : 5780 42 Number of Cells : 2 43 Duplexing Mode : Duplex Mode FDD 44 Neighbor Cells : 45 [0 ] : 46 Cell Id : 219 47 FTL Cumulative frequency offset : 0 48 Inst RSRP Rx[0] : -94.31 dBm 49 Inst RSRP Rx[1] : -96.31 dBm 50 Inst RSRP : -94.31 dBm 51 Inst RSRQ Rx[0] : -19.94 dBm 52 Inst RSRQ Rx[1] : -19.44 dBm 53 Inst RSRQ : -19.44 dBm 54 Inst RSSI Rx[0] : -57.00 dBm 55 Inst RSSI Rx[1] : -59.50 dBm 56 Inst RSSI : -44.00 dBm 57 [1 ] : 58 Cell Id : 287 59 FTL Cumulative frequency offset : 0 60 Inst RSRP Rx[0] : -106.31 dBm 61

31


Inst RSRP Rx[1] : -100.75 dBm 1 Inst RSRP : -100.75 dBm 2 Inst RSRQ Rx[0] : -30.00 dBm 3 Inst RSRQ Rx[1] : -23.88 dBm 4 Inst RSRQ : -23.88 dBm 5 Inst RSSI Rx[0] : -57.00 dBm 6 Inst RSSI Rx[1] : -59.50 dBm 7 Inst RSSI : -44.00 dBm 8 9 RRC Connection Request (UL-CCCH) 10 11 Time : 18:33:03.250 12 Vendor Header 13 Length : 31 14 Log Code (Hex) : 0xB0C0 15 HW Timestamp : (84781946.25 ms) 23:33:01.946 16 1.25 ms fraction : 0.00 17 CFN : 76 18 1.25 ms counter : 803449585557 19 RRC Signaling Header 20 Log Packet Version : 1 21 RRC Release Number : 8.7.0 22 Radio Bearer Id : 0 23 Physical Cell Id : 220 24 E-ARFCN : 5780 25 System Frame Number 26 System frame number : N/A 27 Sub frame number : N/A 28 Message Type : CcchUplink 29 Message Length : 6 30 criticalExtensions : rrcConnectionRequest-r8 31 rrcConnectionRequest-r8 32 ue-Identity 33 InitialUE-Identity : s-TMSI 34 s-TMSI 35 mmec 36 Binary string (Bin) : 00000010 37 [0 ] : 0 38 [1 ] : 0 39 [2 ] : 0 40 [3 ] : 0 41 [4 ] : 0 42 [5 ] : 0 43 [6 ] : 1 44 [7 ] : 0 45 m-TMSI : 11110000000001100011010100110100 46 [0 ] : 1 47 [1 ] : 1 48 [2 ] : 1 49 [3 ] : 1 50 [4 ] : 0 51 [5 ] : 0 52 [6 ] : 0 53 [7 ] : 0 54 [8 ] : 0 55 [9 ] : 0 56 [10] : 0 57 [11] : 0 58 [12] : 0 59 [13] : 1 60 [14] : 1 61 [15] : 0 62 [16] : 0 63

32


[17] : 0 1 [18] : 1 2 [19] : 1 3 [20] : 0 4 [21] : 1 5 [22] : 0 6 [23] : 1 7 [24] : 0 8 [25] : 0 9 [26] : 1 10 [27] : 1 11 [28] : 0 12 [29] : 1 13 [30] : 0 14 [31] : 0 15 establishmentCause : mo-Data 16 spare : 0 17 [0 ] : 0 18 19 ML1 Random Access Request 20 21 Time : 18:33:03.250 22 Length : 40 23 Log Code (Hex) : 0xB167 24 HW Timestamp : (84781991.25 ms) 23:33:01.991 25 1.25 ms fraction : 0.00 26 CFN : 40 27 1.25 ms counter : 803449585593 28 Version : 5 29 Preamble Sequence : 30 30 Physical Root Index : 22 31 Cyclic Shift : 238 32 PRACH Tx Power : -16 33 Beta PRACH : 242 34 PRACH Frequency Offset : 2 35 Preamble Format : 0 36 Duplex Mode : FDD 37 PRACH Timing SFN : 823 38 PRACH Timing Sub-fn : 4 39 PRACH Window Start SFN : 823 40 PRACH Window Start Sub-fn : 7 41 PRACH Window End SFN : 824 42 PRACH Window End Sub-fn : 1 43 RA RNTI : 5 44 PRACH Actual Tx Power : 240 45 46 LL1 RACH Tx Report 47 48 Time : 18:33:03.250 49 Length : 24 50 Log Code (Hex) : 0xB144 51 HW Timestamp : (84781992.50 ms) 23:33:01.992 52 1.25 ms fraction : 0.00 53 CFN : 124 54 1.25 ms counter : 803449585594 55 Version : 2 56 Current SFN SF : 8234 57 Preamble Sequence : 30 58 Cycle Shift : 238 59 Preamble Format : 0 60 First RB for PRACH Opportunity : 2 61 Start RB : 2 62 PRACH Transmit Power : -16 63

33


Logical Root (q) : 22 1 2 ML1 Random Access Response 3 4 Time : 18:33:03.250 5 Length : 24 6 Log Code (Hex) : 0xB168 7 HW Timestamp : (84781998.75 ms) 23:33:01.999 8 1.25 ms fraction : 0.00 9 CFN : 136 10 1.25 ms counter : 803449585599 11 Version : 1 12 PRACH Response Timing SFN : 823 13 PRACH Response Timing Sub-fn : 8 14 Timing Advance : 7 15 Timing Advance Included : Included 16 RACH Procedure Type : Contention Based 17 RACH Procedure Mode : Initial Access 18 RNTI Type : TEMP_C_RNTI 19 RNTI Value : 49575 20

34


[3] Answer the following questions regarding the UE Log File ATT_Drive_Test.log, which is located in the

preceding section.

a) What triggered the RA process? (Hint: See the Establishment cause for the RRC Connection Request)

b) Based on the ML1 Random Access Request report, provide the following information regarding the

preamble:

Preamble Sequence: RA RNTI:

Preamble Format: _____________ PRACH Tx Power: ______________

c) Based on the ML1 Random Access Response report, answer the following:

Was this a successful Random Access attempt?

A RNTI (49575) is piggy-backed in this message. What role does it play?_________________________

What is the Timing Advance value? _______

Can you determine the approximate distance between the UE and the cell antenna based on the TA?

________

After a successful RA procedure the L3 message (RRC Conn. Req.) will be sent. Why does the log show

the Random Access procedure happening after the RRC message?

________

At what power will the RRC message will be sent?

d) How many times will the RACH counter at the eNB be pegged for this UE’s access attempt? What type of

counter will be pegged (CBRA or CFRA?)

35


4.1.11 Random Access Counters

In this section, Random Access-related counters will be discussed.


pmRaAttCbra Pegged when the eNodeB receives a contention based random access preamble

pmRaSuccCbra Pegged when the eNodeB successfully receives a L3 message as a direct result of a

contention based random access preamble. A RRC Connection Request message would

be an example. A L3 message is considered successfully received if its CRC is correct.

pmRaAttCfra This counter is incremented whenever a CFRA preamble that has been allocated to a UE

is detected in the Cell.

pmRaSuccCfra This counter is incremented when an UL-SCH message is successfully detected after a

CFRA preamble has been received.

pmRaFailCbraMsg2Disc The number of CBRA preambles for which no random access response (RA Msg2) was

sent. This counter should be incremented when the RA response window expires before

an RA response has been sent for a detected CBRA preamble.

[4] For the following questions, refer to the counter file Accessibility.xlsx, which is located on the class

jump drive.

a) Consider rows with RRC_EstablishmentAtt >= 1000; this will remove statistically insignificant data. Sort on the

ContentionBased_RA_Fail% column and provide the following regarding the cell with the highest failure

percent:

eNodeB:

CBRA Success percent:

Number of CBRA attempts:

Number of CBRA successes:

b) What is the average CBRA failure percentage for all cells on this day (continue to filter out low data points)?

________

________

c) Can you think of a reason why this failure rate is so high?

________

________

________

________

________

________

36


4.2 RRC Connection Setup Procedure

This section will investigate the RRC Connection Setup Procedure.

Figure 4: RRC Connection Setup

4.2.1 RRC Connection Setup (eNodeB Cell Trace)

Reference: RRC.txt FSL00229;15918;8457873;15:28:42:970;UE;ERBS;0;680229-23;Unavailable;RRC; 1 RRC_RRC_CONNECTION_REQUEST; 2 value UL-CCCH-Message ::= 3 message c1 : rrcConnectionRequest : 4 criticalExtensions rrcConnectionRequest-r8 : 5 ue-Identity s-TMSI : 6 mmec '00001001'B, 7 m-TMSI '11000000 10000111 11001110 11001101'B 8 , 9 establishmentCause mo-Data, 10 spare '0'B 11 12 13 14 15 16 FSL00229;15919;8457873;15:28:42:977;ERBS;UE;0;680229-23;Unavailable;RRC; 17 RRC_RRC_CONNECTION_SETUP; 18 value DL-CCCH-Message ::= 19 message c1 : rrcConnectionSetup : 20 rrc-TransactionIdentifier 0, 21 criticalExtensions c1 : rrcConnectionSetup-r8 : 22 radioResourceConfigDedicated 23 srb-ToAddModList 24 25 srb-Identity 1, 26 rlc-Config explicitValue : am : 27

37


ul-AM-RLC 1 t-PollRetransmit ms80, 2 pollPDU pInfinity, 3 pollByte kBinfinity, 4 maxRetxThreshold t32 5 , 6 dl-AM-RLC 7 t-Reordering ms35, 8 t-StatusProhibit ms0 9 10 , 11 logicalChannelConfig explicitValue : 12 ul-SpecificParameters 13 priority 1, 14 prioritisedBitRate infinity, 15 bucketSizeDuration ms50, 16 logicalChannelGroup 0 17 18 19 20 , 21 mac-MainConfig explicitValue : 22 ul-SCH-Config 23 maxHARQ-Tx n4, 24 periodicBSR-Timer sf5, 25 retxBSR-Timer sf320, 26 ttiBundling FALSE 27 , 28 timeAlignmentTimerDedicated infinity, 29 phr-Config setup : 30 periodicPHR-Timer sf200, 31 prohibitPHR-Timer sf200, 32 dl-PathlossChange dB3 33 34 , 35 physicalConfigDedicated 36 pdsch-ConfigDedicated 37 p-a dB-3 38 , 39 pusch-ConfigDedicated 40 betaOffset-ACK-Index 10, 41 betaOffset-RI-Index 9, 42 betaOffset-CQI-Index 10 43 , 44 cqi-ReportConfig 45 cqi-ReportModeAperiodic rm30, 46 nomPDSCH-RS-EPRE-Offset 0, 47 cqi-ReportPeriodic setup : 48 cqi-PUCCH-ResourceIndex 0, 49 cqi-pmi-ConfigIndex 77, 50 cqi-FormatIndicatorPeriodic widebandCQI : NULL, 51 ri-ConfigIndex 322, 52 simultaneousAckNackAndCQI FALSE 53 54 , 55 antennaInfo explicitValue : 56 transmissionMode tm3, 57 codebookSubsetRestriction n2TxAntenna-tm3 : '11'B, 58 ue-TransmitAntennaSelection release : NULL 59 , 60 schedulingRequestConfig setup : 61 sr-PUCCH-ResourceIndex 0, 62 sr-ConfigIndex 7, 63

38


dsr-TransMax n64 1 2 3 4 5 6 7 8 9 FSL00229;15920;8457873;15:28:43:010;UE;ERBS;0;680229-23;Unavailable;RRC; 10 RRC_RRC_CONNECTION_SETUP_COMPLETE; 11 value UL-DCCH-Message ::= 12 message c1 : rrcConnectionSetupComplete : 13 rrc-TransactionIdentifier 0, 14 criticalExtensions c1 : rrcConnectionSetupComplete-r8 : 15 selectedPLMN-Identity 1, 16 dedicatedInfoNAS 'C707A3CC'H 17 18 19 20 21 22 FSL00229;15922;8457873;15:28:43:010;ERBS;;0;680229-23;Unavailable;INTERNAL_PROC; 23 INTERNAL_PROC_RRC_CONN_SETUP; 24 INITIAL_UE_IDENTITY_TYPE: Unavailable 25 INITIAL_UE_IDENTITY: '0009C087CECD'H 26 RRC_ESTABL_CAUSE: MO_DATA 27 RRC_RESULT: SUCCESS 28 TIMESTAMP_START_HOUR: 15 29 TIMESTAMP_START_MINUTE: 28 30 TIMESTAMP_START_SECOND: 42 31 TIMESTAMP_START_MILLISEC: 971 32 TIMESTAMP_STOP_HOUR: 15 33 TIMESTAMP_STOP_MINUTE: 28 34 TIMESTAMP_STOP_SECOND: 43 35 TIMESTAMP_STOP_MILLISEC: 10 36

39


4.2.2 RRCConnectionRequest (from Specifications)


The RRCConnectionRequest message is used to request the establishment of an RRC connection.

Signaling radio bearer: SRB0, RLC-SAP: TM, Logical channel: CCCH, Direction: UE to E-UTRAN -- ASN1START 1 2 RRCConnectionRequest ::= SEQUENCE 3 criticalExtensions CHOICE 4 rrcConnectionRequest-r8 RRCConnectionRequest-r8-IEs, 5 criticalExtensionsFuture SEQUENCE 6 7 8 9 RRCConnectionRequest-r8-IEs ::= SEQUENCE 10 ue-Identity InitialUE-Identity, 11 establishmentCause EstablishmentCause, 12 spare BIT STRING (SIZE (1)) 13 14 15 InitialUE-Identity ::= CHOICE 16 s-TMSI S-TMSI, 17 randomValue BIT STRING (SIZE (40)) 18 19 20 EstablishmentCause ::= ENUMERATED 21 emergency, highPriorityAccess, mt-Access, mo-Signalling, 22 mo-Data, spare3, spare2, spare1 23 24 -- ASN1STOP 25

4.2.3 RandomValue IE (from Specifications)

Reference: (3GPP TS 36.331 Section 6.2.2) Integer value in the range 0 to 2

40 - 1. 26

4.2.4 RRCConnectionSetup (from Specifications)


The RRCConnectionSetup message is used to establish SRB1.

Signaling radio bearer: SRB0, RLC-SAP: TM, Logical channel: CCCH, Direction: E-UTRAN to UE -- ASN1START 27 28 RRCConnectionSetup ::= SEQUENCE 29 rrc-TransactionIdentifier RRC-TransactionIdentifier, 30 criticalExtensions CHOICE 31 c1 CHOICE 32 rrcConnectionSetup-r8 RRCConnectionSetup-r8-IEs, 33 spare7 NULL, 34 spare6 NULL, spare5 NULL, spare4 NULL, 35 spare3 NULL, spare2 NULL, spare1 NULL 36 , 37 criticalExtensionsFuture SEQUENCE 38 39 40 41 RRCConnectionSetup-r8-IEs ::= SEQUENCE 42 radioResourceConfigDedicated RadioResourceConfigDedicated, 43 nonCriticalExtension SEQUENCE OPTIONAL -- Need 44 OP 45 46 47 -- ASN1STOP 48 49

40


4.2.5 RadioResourceConfigDedicated IE (from Specifications)


The IE RadioResourceConfigDedicated is used to setup/modify/release RBs, to modify the MAC main

configuration, to modify the SPS configuration and to modify the dedicated physical configuration. -- ASN1START 1 2 RadioResourceConfigDedicated ::= SEQUENCE 3 srb-ToAddModList SRB-ToAddModList OPTIONAL, -- Cond HO-4 Conn 5 drb-ToAddModList DRB-ToAddModList OPTIONAL, -- Cond HO-6 toEUTRA 7 drb-ToReleaseList DRB-ToReleaseList OPTIONAL, -- Need ON 8 mac-MainConfig CHOICE 9 explicitValue MAC-MainConfig, 10 defaultValue NULL 11 OPTIONAL, -- Cond HO-12 toEUTRA2 13 sps-Config SPS-Config OPTIONAL, -- Need ON 14 physicalConfigDedicated PhysicalConfigDedicated OPTIONAL, -- Need ON 15 ... 16 17 18 SRB-ToAddModList ::= SEQUENCE (SIZE (1..2)) OF SRB-ToAddMod 19 20 SRB-ToAddMod ::= SEQUENCE 21 srb-Identity INTEGER (1..2), 22 rlc-Config CHOICE 23 explicitValue RLC-Config, 24 defaultValue NULL 25 OPTIONAL, -- Cond Setup 26 logicalChannelConfig CHOICE 27 explicitValue LogicalChannelConfig, 28 defaultValue NULL 29 OPTIONAL, -- Cond Setup 30 ... 31 32 33 DRB-ToAddModList ::= SEQUENCE (SIZE (1..maxDRB)) OF DRB-ToAddMod 34 35 DRB-ToAddMod ::= SEQUENCE 36 eps-BearerIdentity INTEGER (0..15) OPTIONAL, -- Cond DRB-Setup 37 drb-Identity DRB-Identity, 38 pdcp-Config PDCP-Config OPTIONAL, -- Cond PDCP 39 rlc-Config RLC-Config OPTIONAL, -- Cond Setup 40 logicalChannelIdentity INTEGER (3..10) OPTIONAL, -- Cond DRB-Setup 41 logicalChannelConfig LogicalChannelConfig OPTIONAL, -- Cond Setup 42 ... 43 44 45 DRB-ToReleaseList ::= SEQUENCE (SIZE (1..maxDRB)) OF DRB-Identity 46 47 -- ASN1STOP 48

41


4.2.6 RRCConnectionSetupComplete (from Specifications)


The RRCConnectionSetupComplete message is used to confirm the successful completion of an RRC

connection establishment.

Signaling radio bearer: SRB1, RLC-SAP: AM, Logical channel: DCCH, Direction: UE to E-UTRAN -- ASN1START 1 2 RRCConnectionSetupComplete ::= SEQUENCE 3 rrc-TransactionIdentifier RRC-TransactionIdentifier, 4 criticalExtensions CHOICE 5 c1 CHOICE 6 rrcConnectionSetupComplete-r8 RRCConnectionSetupComplete-r8-IEs, 7 spare3 NULL, spare2 NULL, spare1 NULL 8 , 9 criticalExtensionsFuture SEQUENCE 10 11 12 13 RRCConnectionSetupComplete-r8-IEs ::= SEQUENCE 14 selectedPLMN-Identity INTEGER (1..6), 15 registeredMME RegisteredMME OPTIONAL, 16 dedicatedInfoNAS DedicatedInfoNAS, 17 nonCriticalExtension SEQUENCE OPTIONAL 18 19 20 RegisteredMME ::= SEQUENCE 21 plmn-Identity PLMN-Identity OPTIONAL, 22 mmegi BIT STRING (SIZE (16)), 23 mmec MMEC 24 25 26 -- ASN1STOP 27

42


4.2.7 RRC Connection Setup Counters

In this section, RRC Connection Setup-related counters will be discussed.


pmRrcConnEstabAtt Pegged upon reception of an RRC Connection Request message.

pmRrcConnEstabSucc Pegged upon reception of an RRC Connection Setup Complete message.

pmRrcConnEstabAttReatt The total number of RRC Connection Request attempts that are considered as re-

attempts. Pegged at reception of RRC message RRC Connection Request while an

RRC Connection Setup is already ongoing for that S-TMSI.

pmRrcConnEstabFailLic The total number of failed RRC Connection Establishments due to lack of connected

users license.

pmRrcConnEstabFailHighLoad The total number of failed RRC Connection Establishments due to high load.

pmRrcConnEstabFailOverload The total number of failed RRC Connection Establishments due to overload.

pmRrcConnEstabFailBearerAd

missionRej

The total number of failed establishment of RRC Connection due to the fact that all

the UE's bearers are rejected during bearer admission.

43



jump drive.

a) Consider rows with RRC_EstablishmentAtt >= 1000; this will remove statistically insignificant data. Sort on

the RRC_Setup_Failure % column and provide the following regarding the cell with the highest failure percent:

• Cell: _______________________________

• RRC_Setup_Failure %: ________________

• Number of RRC connection attempts: __________________________

• Number of RRC connection failures: _________________________ __

• Number of RRC connection successes: ________________________

b) Why is the failure rate so high? What would you do to improve this KPI?

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

44


4.3 S1 Signaling Bearer Setup Procedure

This section will investigate the S1 Signaling Bearer Setup phase of the call setup procedure.

Figure 5: S1 Signaling Connection Establishment

4.3.1 S1 Connection Setup Procedure (eNodeB Cell Trace)

Reference: RRC.txt FSL00229;15921;8457873;15:28:43:010;ERBS;MME;0;680229-23;Unavailable;S1AP; 1 S1_INITIAL_UE_MESSAGE; 2 value S1AP-PDU ::= initiatingMessage : 3 procedureCode 12, 4 criticality ignore, 5 value InitialUEMessage : 6 protocolIEs 7 8 id 8, 9 criticality reject, 10 value ENB-UE-S1AP-ID : 2457 11 , 12 13 id 26, 14 criticality reject, 15 value NAS-PDU : 'C707A3CC'H 16 , 17 18 id 67, 19 criticality reject, 20 value TAI : 21 pLMNidentity '134001'H, 22 tAC '370F'H 23 24 , 25

45


1 id 100, 2 criticality ignore, 3 value EUTRAN-CGI : 4 pLMNidentity '134001'H, 5 cell-ID '10100110 00010010 01010001 0111'B 6 7 , 8 9 id 134, 10 criticality ignore, 11 value RRC-Establishment-Cause : mo-Data 12 , 13 14 id 96, 15 criticality reject, 16 value S-TMSI : 17 mMEC '09'H, 18 m-TMSI 'C087CECD'H 19 20 21 22 23 24 25 FSL00229;15921;8457873;15:28:43:010;MME;ERBS;0;680229-23;Unavailable;S1AP; 26 S1_DOWNLINK_NAS_TRANSPORT; 27 value S1AP-PDU ::= initiatingMessage : 28 procedureCode 11, 29 criticality ignore, 30 value DownlinkNASTransport : 31 protocolIEs 32 33 id 0, 34 criticality reject, 35 value MME-UE-S1AP-ID : 279213029 36 , 37 38 id 8, 39 criticality reject, 40 value ENB-UE-S1AP-ID : 2457 41 , 42 43 id 26, 44 criticality reject, 45 value NAS-PDU : '075501'H 46 47 48 49 50 51 FSL00229;15924;8457873;15:28:43:049;ERBS;;0;680229-23;279213029;INTERNAL_PROC; 52 INTERNAL_PROC_S1_SIG_CONN_SETUP; 53 RRC_ESTABL_CAUSE: MO_DATA 54 S1_SIG_CONN_RESULT: SUCCESS 55 TIMESTAMP_START_HOUR: 15 56 TIMESTAMP_START_MINUTE: 28 57 TIMESTAMP_START_SECOND: 43 58 TIMESTAMP_START_MILLISEC: 10 59 TIMESTAMP_STOP_HOUR: 15 60 TIMESTAMP_STOP_MINUTE: 28 61 TIMESTAMP_STOP_SECOND: 43 62 TIMESTAMP_STOP_MILLISEC: 10 63

46


4.3.2 Initial UE Message (from Specifications)

Reference: (3GPP TS 36.413 Section 9.3.3) InitialUEMessage ::= SEQUENCE 1 protocolIEs ProtocolIE-Container InitialUEMessage-IEs, 2 ... 3 4 5 InitialUEMessage-IEs S1AP-PROTOCOL-IES ::= 6 ID id-eNB-UE-S1AP-ID CRITICALITY reject TYPE ENB-UE-S1AP-ID 7 PRESENCE mandatory | 8 ID id-NAS-PDU CRITICALITY reject TYPE NAS-PDU 9 PRESENCE mandatory | 10 ID id-TAI CRITICALITY reject TYPE TAI 11 PRESENCE mandatory | 12 ID id-EUTRAN-CGI CRITICALITY ignore TYPE EUTRAN-CGI 13 PRESENCE mandatory | 14 ID id-RRC-Establishment-Cause CRITICALITY ignore TYPE RRC-Establishment-Cause 15 PRESENCE mandatory | 16 ID id-S-TMSI CRITICALITY reject TYPE S-TMSI 17 PRESENCE optional | 18 ID id-CSG-Id CRITICALITY reject TYPE CSG-Id 19 PRESENCE optional | 20 ID id-GUMMEI-ID CRITICALITY reject TYPE GUMMEI 21 PRESENCE optional, 22 ... 23 24

4.3.3 Downlink NAS Transport (from Specifications)

Reference: (3GPP TS 36.413 Section 9.3.3) DownlinkNASTransport ::= SEQUENCE 25 protocolIEs ProtocolIE-Container DownlinkNASTransport-IEs, 26 ... 27 28 29 DownlinkNASTransport-IEs S1AP-PROTOCOL-IES ::= 30 ID id-MME-UE-S1AP-ID CRITICALITY reject TYPE MME-UE-S1AP-ID PRESENCE 31 mandatory | 32 ID id-eNB-UE-S1AP-ID CRITICALITY reject TYPE ENB-UE-S1AP-ID PRESENCE 33 mandatory | 34 ID id-NAS-PDU CRITICALITY reject TYPE NAS-PDU PRESENCE 35 mandatory | 36 ID id-HandoverRestrictionList CRITICALITY ignore TYPE HandoverRestrictionList37 PRESENCE optional , 38 ... 39 40

4.3.4 S1 Connection Setup Counters

In this section, S1 Connection Setup counters will be discussed.


pmS1SigConnEstabAtt Pegged upon transmission of a S1 Initial UE Message.

pmS1SigConnEstabSucc Pegged upon reception of an S1 Initial Context Setup Request message. Pegged at the

first occurrence of reception of any message on this S1 logical connection.

47



jump drive.

4.4 E-RAB Setup Procedure

This section will review the last phase of the call setup procedure, the E-RAB setup procedure.

Figure 6: E-RAB Setup Procedure

c) Consider rows with pmS1SigConnEstabAtt >= 1000; this will remove statistically insignificant data. Sort on the

S1_Setup_Failure % column and provide the following regarding the cell with the highest failure percent:

• Cell: __________________________

• S1_Setup_Failure %: __________________________

• Number of S1 connection setup attempts: _________________________

• Number of S1 connection setup successes: ________________________

d) Is the S1 setup failure % high? If yes, why? (Check the alarm logs from the OSS Element manager and/or

Quantum to answer the question).

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

48


4.4.1 Initial Context Setup Request and RRC Reconfiguration

Reference: RRC.txt FSL00229;15923;8457873;15:28:43:049;MME;ERBS;0;680229-23;279213029;S1AP; 1 S1_INITIAL_CONTEXT_SETUP_REQUEST; 2 value S1AP-PDU ::= initiatingMessage : 3 procedureCode 9, 4 criticality reject, 5 value InitialContextSetupRequest : 6 protocolIEs 7 8 id 0, 9 criticality reject, 10 value MME-UE-S1AP-ID : 279213029 11 , 12 13 id 8, 14 criticality reject, 15 value ENB-UE-S1AP-ID : 2457 16 , 17 18 id 66, 19 criticality reject, 20 value UEAggregateMaximumBitrate : 21 uEaggregateMaximumBitRateDL 70000000, 22 uEaggregateMaximumBitRateUL 25000000 23 24 , 25 26 id 24, 27 criticality reject, 28 value E-RABToBeSetupListCtxtSUReq : 29 30 id 52, 31 criticality reject, 32 value E-RABToBeSetupItemCtxtSUReq : 33 e-RAB-ID 5, 34 e-RABlevelQoSParameters 35 qCI 8, 36 allocationRetentionPriority 37 priorityLevel 10, 38 pre-emptionCapability shall-not-trigger-pre-emption, 39 pre-emptionVulnerability pre-emptable 40 41 , 42 transportLayerAddress '10100110 10010011 01111000 11101110'B, 43 gTP-TEID 'C2F4357A'H 44 45 46 47 , 48 49 id 107, 50 criticality reject, 51 value UESecurityCapabilities : 52 encryptionAlgorithms '11000000 00000000'B, 53 integrityProtectionAlgorithms '11000000 00000000'B 54 55 , 56 57 id 73, 58 criticality reject, 59

49


value SecurityKey : '11111111 11111111 11111111 11111111 111'B -- truncated -- 1 , 2 3 id 41, 4 criticality ignore, 5 value HandoverRestrictionList : 6 servingPLMN '134001'H, 7 forbiddenInterRATs cdma2000 8 9 , 10 11 id 74, 12 criticality ignore, 13 value UERadioCapability : 14 '013001023C520000304184200E1F8FFF0FC7FF87E3FFC3F1FFDF83FF2022060090E194'H -- 15 16 truncated -- 17 18 19 20 21 22 23 FSL00229;16264;8457873;15:28:49:063;ERBS;UE;0;680229-23;282460628;RRC; 24 RRC_RRC_CONNECTION_RECONFIGURATION; 25 value DL-DCCH-Message ::= 26 message c1 : rrcConnectionReconfiguration : 27 rrc-TransactionIdentifier 0, 28 criticalExtensions c1 : rrcConnectionReconfiguration-r8 : 29 measConfig 30 measObjectToAddModList 31 32 measObjectId 1, 33 measObject measObjectEUTRA : 34 carrierFreq 2175, 35 allowedMeasBandwidth mbw25, 36 presenceAntennaPort1 TRUE, 37 neighCellConfig '10'B 38 39 40 , 41 reportConfigToAddModList 42 43 reportConfigId 1, 44 reportConfig reportConfigEUTRA : 45 triggerType event : 46 eventId eventA3 : 47 a3-Offset 6, 48 reportOnLeave FALSE 49 , 50 hysteresis 2, 51 timeToTrigger ms320 52 , 53 triggerQuantity rsrp, 54 reportQuantity both, 55 maxReportCells 4, 56 reportInterval ms480, 57 reportAmount infinity 58 59 , 60 61 reportConfigId 2, 62 reportConfig reportConfigEUTRA : 63

50


triggerType event : 1 eventId eventA2 : 2 a2-Threshold threshold-RSRP : 28 3 , 4 hysteresis 2, 5 timeToTrigger ms1280 6 , 7 triggerQuantity rsrp, 8 reportQuantity both, 9 maxReportCells 4, 10 reportInterval ms480, 11 reportAmount infinity 12 13 , 14 15 reportConfigId 3, 16 reportConfig reportConfigEUTRA : 17 triggerType event : 18 eventId eventA2 : 19 a2-Threshold threshold-RSRP : 24 20 , 21 hysteresis 2, 22 timeToTrigger ms1280 23 , 24 triggerQuantity rsrp, 25 reportQuantity both, 26 maxReportCells 4, 27 reportInterval ms480, 28 reportAmount infinity 29 30 , 31 32 reportConfigId 4, 33 reportConfig reportConfigEUTRA : 34 triggerType event : 35 eventId eventA3 : 36 a3-Offset 0, 37 reportOnLeave FALSE 38 , 39 hysteresis 2, 40 timeToTrigger ms320 41 , 42 triggerQuantity rsrp, 43 reportQuantity both, 44 maxReportCells 4, 45 reportInterval ms480, 46 reportAmount r1 47 48 49 , 50 measIdToAddModList 51 52 measId 1, 53 measObjectId 1, 54 reportConfigId 1 55 , 56 57 measId 2, 58 measObjectId 1, 59 reportConfigId 2 60 , 61 62 measId 3, 63

51


measObjectId 1, 1 reportConfigId 3 2 , 3 4 measId 4, 5 measObjectId 1, 6 reportConfigId 4 7 8 , 9 quantityConfig 10 quantityConfigEUTRA 11 filterCoefficientRSRP fc9 12 , 13 quantityConfigUTRA 14 measQuantityUTRA-FDD cpich-RSCP, 15 measQuantityUTRA-TDD pccpch-RSCP 16 17 , 18 speedStatePars release : NULL 19 , 20 radioResourceConfigDedicated 21 srb-ToAddModList 22 23 srb-Identity 2, 24 rlc-Config explicitValue : am : 25 ul-AM-RLC 26 t-PollRetransmit ms80, 27 pollPDU pInfinity, 28 pollByte kBinfinity, 29 maxRetxThreshold t32 30 , 31 dl-AM-RLC 32 t-Reordering ms35, 33 t-StatusProhibit ms0 34 35 , 36 logicalChannelConfig explicitValue : 37 ul-SpecificParameters 38 priority 3, 39 prioritisedBitRate infinity, 40 bucketSizeDuration ms50, 41 logicalChannelGroup 0 42 43 44 45 , 46 drb-ToAddModList 47 48 eps-BearerIdentity 5, 49 drb-Identity 3, 50 pdcp-Config 51 discardTimer ms300, 52 rlc-AM 53 statusReportRequired FALSE 54 , 55 headerCompression notUsed : NULL 56 , 57 rlc-Config am : 58 ul-AM-RLC 59 t-PollRetransmit ms80, 60 pollPDU p16, 61 pollByte kBinfinity, 62 maxRetxThreshold t16 63

52


, 1 dl-AM-RLC 2 t-Reordering ms35, 3 t-StatusProhibit ms25 4 5 , 6 logicalChannelIdentity 3, 7 logicalChannelConfig 8 ul-SpecificParameters 9 priority 11, 10 prioritisedBitRate kBps8, 11 bucketSizeDuration ms50, 12 logicalChannelGroup 1 13 14 15 16 , 17 mac-MainConfig explicitValue : 18 drx-Config setup : 19 onDurationTimer psf10, 20 drx-InactivityTimer psf200, 21 drx-RetransmissionTimer psf2, 22 longDRX-CycleStartOffset sf320 : 161, 23 shortDRX 24 shortDRX-Cycle sf20, 25 drxShortCycleTimer 1 26 27 , 28 timeAlignmentTimerDedicated infinity 29 , 30 physicalConfigDedicated 31 soundingRS-UL-ConfigDedicated setup : 32 srs-Bandwidth bw0, 33 srs-HoppingBandwidth hbw0, 34 freqDomainPosition 0, 35 duration TRUE, 36 srs-ConfigIndex 25, 37 transmissionComb 0, 38 cyclicShift cs3 39 40 41 42 43 44 45

53


4.4.2 RRCConnection Reconfiguration (from Specifications)


The RRCConnectionReconfiguration message is the command to modify an RRC connection. It may convey

information for measurement configuration, mobility control, radio resource configuration (including RBs, MAC

main configuration and physical channel configuration), including any associated dedicated NAS information

and security configuration.

Signaling radio bearer: SRB1, RLC-SAP: AM, Logical channel: DCCH, Direction: E-UTRAN to UE -- ASN1START 1 2 RRCConnectionReconfiguration ::= SEQUENCE 3 rrc-TransactionIdentifier RRC-TransactionIdentifier, 4 criticalExtensions CHOICE 5 c1 CHOICE 6 rrcConnectionReconfiguration-r8 RRCConnectionReconfiguration-r8-IEs, 7 spare7 NULL, 8 spare6 NULL, spare5 NULL, spare4 NULL, 9 spare3 NULL, spare2 NULL, spare1 NULL 10 , 11 criticalExtensionsFuture SEQUENCE 12 13 14 15 RRCConnectionReconfiguration-r8-IEs ::= SEQUENCE 16 measConfig MeasConfig OPTIONAL, -- Need ON 17 mobilityControlInfo MobilityControlInfo OPTIONAL, -- Cond HO 18 dedicatedInfoNASList SEQUENCE (SIZE(1..maxDRB)) OF 19 DedicatedInfoNAS OPTIONAL, -- Cond nonHO 20 radioResourceConfigDedicated RadioResourceConfigDedicated OPTIONAL, -- Cond HO-21 toEUTRA 22 securityConfigHO SecurityConfigHO OPTIONAL, -- Cond HO 23 nonCriticalExtension SEQUENCE OPTIONAL -- Need OP 24 25 26 SecurityConfigHO ::= SEQUENCE 27 handoverType CHOICE 28 intraLTE SEQUENCE 29 securityAlgorithmConfig SecurityAlgorithmConfig OPTIONAL, -- Need 30 OP 31 keyChangeIndicator BOOLEAN, 32 nextHopChainingCount NextHopChainingCount 33 , 34 interRAT SEQUENCE 35 securityAlgorithmConfig SecurityAlgorithmConfig, 36 nas-SecurityParamToEUTRA OCTET STRING (SIZE(6)) 37 38 , 39 ... 40 41

54


4.4.3 RRCConnection Reconfiguration Complete (from Specifications)


The RRCConnectionReconfigurationComplete message is used to confirm the successful completion of an RRC

connection reconfiguration.

Signaling radio bearer: SRB1, RLC-SAP: AM, Logical channel: DCCH, Direction: UE to E-UTRAN -- ASN1START 1 2 RRCConnectionReconfigurationComplete ::= SEQUENCE 3 rrc-TransactionIdentifier RRC-TransactionIdentifier, 4 criticalExtensions CHOICE 5 rrcConnectionReconfigurationComplete-r8 6 RRCConnectionReconfigurationComplete-r8-IEs, 7 criticalExtensionsFuture SEQUENCE 8 9 10 11 RRCConnectionReconfigurationComplete-r8-IEs ::= SEQUENCE 12 nonCriticalExtension SEQUENCE OPTIONAL 13 14

4.4.4 E-RAB Setup Counters

In this section, the E-RAB setup counters will be discussed.


pmErabEstabAttInit Pegged upon reception of a S1 Initial Context Setup Request message

pmErabEstabSuccInit Pegged upon transmission of a S1 Initial Context Setup Response message

pmErabEstabFailInitLic The total number of failed establishment of initial E-RABs due to license rejects (Multiple

Radio Bearer per user or RLC UM). Initial E-RABs are all E-RABs present in the S1

message Initial Context Setup Request.

pmErabEstabAttInitQci The total number of initial E-RAB setup attempts per QCI.

pmErabEstabSuccInitQci The total number of successful initial E-RAB setup per QCI.

55


4.5 eNodeB Trace and Counter Analysis

4.5.1 Counter Analysis

[7] In this exercise, statistics will be used to identify a suspect cell. Answer the following questions.

4.5.2 eNodeB Trace and Counter Analysis

[8] In this exercise, the eNodeB Cell Trace FSL00229_logfile.txt will be used. Answer the following

questions.

a) Refer to the eNodeB Cell Trace FSL00229_logfile.txt. Based on this log file, which of the following will be

pegged? Include the time stamp.

pmRrcConnEstabAtt:

pmRrcConnEstabSucc:

pmS1SigConnEstabAtt:

pmS1SigConnEstabSucc:

pmErabEstabAttInit:

e) Refer to the spreadsheet Exercise4.4_Accessibility.xlsx. Consider rows with RRC_EstablishmentAtt >= 1000;

this will remove statistically insignificant data. For this day, what cell has the highest Total_Initial_Estab_Fail

%?

• Cell: __________________________

• Total_Initial_Estab_Fail %: __________________________

f) For this cell, what is the distribution of failures based on the three components of the Accessibility KPI?

RRC Setup Fail %: ________ S1 Setup Fail %: ________ Initial E-RAB Fail %: ________

g) What is the likely cause of the high rate of failures?

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

_________________________________________________________________________________________

56

5 | Intra-LTE Handover Analysis

5 Intra-LTE Handover Analysis Figure 1 below illustrates the basic call flow of an Intra-LTE Handover. The various stages will be detailed in the

following sections.

Figure 1: Basic Intra-LTE Handover Call Flow

57


5.1 Intra-Frequency Handover

Prior to examining the details of the various stages of intra-frequency handover, the vendor-specific

parameters related to Event A3 will be examined.

5.1.1 Event A3 Algorithm

This picture illustrates the key ideas behind the Event A3 Measurement and Reporting Algorithm as

implemented on the UE.

Figure 2: Event A3 Algorithm

58


5.1.1.1 Periodical Reporting of Event A3 This picture illustrates the how Periodical Reporting aspect of the Event A3 Measurement and Reporting

Algorithm as implemented on the UE.

Figure 3: Periodical Reporting of Event A3

59


5.1.1.2 Handover-Related Parameters This section provides details about the parameters related to LTE intra-frequency handover. The parameters

are listed by the Managed Object in which they reside. The Managed Object defines how a parameter is

logically segregated within the vendor software and at what element it can be configured (i.e., eNodeB, Cell, or

Neighbor).

5.1.1.2.1 ReportConfigEUtraBestCell MO The following vendor parameters are part of the ReportConfigEUtraBestCell Managed Object and are

configurable at the cell level: 3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

a3-Offset a3offset (-150, -145, … 145, 150) 0.1 dB Resolution

hysteresis hysteresisA3 (0, 5, … 145, 150) 0.1 dB Resolution

timeToTrigger timeToTriggerA3 (0, 40, 64, 80, 100, 128, 160,

256, 320, 480, 512, 640, 1024,

1280, 2560, 5120) ms

n/a

triggerQuantity triggerQuantityA3 (RSRP, RSRQ) n/a

reportAmount reportAmountA3 (0, 1, 2, 4, 8, 16, 32, 64) 0 =

Infinity

n/a

reportInterval reportIntervalA3 (MS_120, MS_240, MS_480,

MS_640, MS_1024, MS_5120,

MS_10240, MIN_1, MIN_6,

MIN_12, MIN_30, MIN_60,

MS_2048)

n/a

[1] Using the local market CM dump located on the class jump drive, provide the configured value for the

following parameters.


a) a3offset

b) hysteresisA3

c) timeToTriggerA3

d) triggerQuantityA3

e) a3offsetAnrDelta

5.1.1.2.2 UeMeasControl MO The following vendor parameters are part of the UeMeasControl Managed Object and are configurable at the

cell level. 3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

s-Measure sMeasure (-140, -139, ...-45, -44) dBm,

0 = disabled

1 dBm

filterCoefficientRSRP filterCoefficientEUtraRsrp (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13,

15, 17, 19)

n/a

60


[2] Using the local market CmDump located on the class jump drive, provide the configured value for the

following parameters.


a) sMeasure

b) filterCoefficientEUtraRsrp

5.1.1.2.3 EUtranCellRelation MO The following vendor parameters are part of the EUtranCellRelation Managed Object and are configurable at

the cell level per neighbor relation. 3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

cellIndividualOffset cellIndividualOffsetEUtran (-24, -22, … -1, 0, 1, … 22, 24) dB 1 dB

5.1.2 Measurement Configuration and UE Measurements

This section will detail the delivery of the Event A3 Measurement.Configuration via the RRC Reconfiguration

Message, as well as UE measurements as they pertain to intra-frequency handover.

Figure 4: Measurement Configuration

61


5.1.2.1 RRC Connection Reconfiguration: Measurement Configuration (eNodeB Cell Trace) Reference: Inter-Freq handover.txt FSL00229;16264;8457873;15:28:49:183;ERBS;UE;0;680229-23;282460628;RRC; 1 RRC_RRC_CONNECTION_RECONFIGURATION; 2 value DL-DCCH-Message ::= 3 message c1 : rrcConnectionReconfiguration : 4 rrc-TransactionIdentifier 1, 5 criticalExtensions c1 : rrcConnectionReconfiguration-r8 : 6 measConfig 7 measObjectToAddModList 8 9 measObjectId 1, 10 measObject measObjectEUTRA : 11 carrierFreq 2175, 12 allowedMeasBandwidth mbw25, 13 presenceAntennaPort1 TRUE, 14 neighCellConfig '10'B 15 16 17 , 18 reportConfigToAddModList 19 20 reportConfigId 1, 21 reportConfig reportConfigEUTRA : 22 triggerType event : 23 eventId eventA3 : 24 a3-Offset 6, 25 reportOnLeave FALSE 26 , 27 hysteresis 2, 28 timeToTrigger ms320 29 , 30 triggerQuantity rsrp, 31 reportQuantity both, 32 maxReportCells 4, 33 reportInterval ms480, 34 reportAmount infinity 35 36 , 37 38 reportConfigId 2, 39 reportConfig reportConfigEUTRA : 40 triggerType event : 41 eventId eventA2 : 42 a2-Threshold threshold-RSRP : 28 43 , 44 hysteresis 2, 45 timeToTrigger ms1280 46 , 47 triggerQuantity rsrp, 48 reportQuantity both, 49 maxReportCells 4, 50 reportInterval ms480, 51 reportAmount infinity 52 53 , 54 55 reportConfigId 3, 56 reportConfig reportConfigEUTRA : 57 triggerType event : 58 eventId eventA2 : 59 a2-Threshold threshold-RSRP : 24 60 , 61

62


hysteresis 2, 1 timeToTrigger ms1280 2 , 3 triggerQuantity rsrp, 4 reportQuantity both, 5 maxReportCells 4, 6 reportInterval ms480, 7 reportAmount infinity 8 9 , 10 11 reportConfigId 4, 12 reportConfig reportConfigEUTRA : 13 triggerType event : 14 eventId eventA3 : 15 a3-Offset 0, 16 reportOnLeave FALSE 17 , 18 hysteresis 2, 19 timeToTrigger ms320 20 , 21 triggerQuantity rsrp, 22 reportQuantity both, 23 maxReportCells 4, 24 reportInterval ms480, 25 reportAmount r1 26 27 28 , 29 measIdToAddModList 30 31 measId 1, 32 measObjectId 1, 33 reportConfigId 1 34 , 35 36 measId 2, 37 measObjectId 1, 38 reportConfigId 2 39 , 40 41 measId 3, 42 measObjectId 1, 43 reportConfigId 3 44 , 45 46 measId 4, 47 measObjectId 1, 48 reportConfigId 4 49 50 , 51 quantityConfig 52 quantityConfigEUTRA 53 filterCoefficientRSRP fc9 54 , 55 quantityConfigUTRA 56 measQuantityUTRA-FDD cpich-RSCP, 57 measQuantityUTRA-TDD pccpch-RSCP 58 59 60 61 62 63

63


1

5.1.2.2 RRC Connection Reconfiguration (from Specifications) Reference: (3GPP TS 36.331 Section 6.2.2) 2 -- ASN1START 3 4 RRCConnectionReconfiguration ::= SEQUENCE 5 rrc-TransactionIdentifier RRC-TransactionIdentifier, 6 criticalExtensions CHOICE 7 c1 CHOICE 8 rrcConnectionReconfiguration-r8 RRCConnectionReconfiguration-r8-IEs, 9 spare7 NULL, 10 spare6 NULL, spare5 NULL, spare4 NULL, 11 spare3 NULL, spare2 NULL, spare1 NULL 12 , 13 criticalExtensionsFuture SEQUENCE 14 15 16 17 RRCConnectionReconfiguration-r8-IEs ::= SEQUENCE 18 measConfig MeasConfig OPTIONAL,-- Need ON 19 mobilityControlInfo MobilityControlInfo OPTIONAL,-- Cond HO 20 dedicatedInfoNASList SEQUENCE (SIZE(1..maxDRB)) OF 21 DedicatedInfoNAS OPTIONAL,-- Cond nonHO 22 radioResourceConfigDedicated RadioResourceConfigDedicated OPTIONAL, -- Cond HO-23 toEUTRA 24 securityConfigHO SecurityConfigHO OPTIONAL,-- Cond HO 25 nonCriticalExtension SEQUENCE OPTIONAL -- Need OP 26 27 28 SecurityConfigHO ::= SEQUENCE 29 handoverType CHOICE 30 intraLTE SEQUENCE 31 securityAlgorithmConfig SecurityAlgorithmConfig OPTIONAL,-- Need OP 32 keyChangeIndicator BOOLEAN, 33 nextHopChainingCount NextHopChainingCount 34 , 35 interRAT SEQUENCE 36 securityAlgorithmConfig SecurityAlgorithmConfig, 37 nas-SecurityParamToEUTRA OCTET STRING (SIZE(6)) 38 39 , 40 ... 41 42 43 -- ASN1STOP 44 45 46

64


5.1.2.3 MeasConfig IE Reference: (3GPP TS 36.331 Section 6.3.5) -- ASN1START 1 2 MeasConfig ::= SEQUENCE 3 -- Measurement objects 4 measObjectToRemoveList MeasObjectToRemoveList OPTIONAL, -- Need ON 5 measObjectToAddModList MeasObjectToAddModList OPTIONAL, -- Need ON 6 -- Reporting configurations 7 reportConfigToRemoveList ReportConfigToRemoveList OPTIONAL, -- Need ON 8 reportConfigToAddModList ReportConfigToAddModList OPTIONAL, -- Need ON 9 -- Measurement identities 10 measIdToRemoveList MeasIdToRemoveList OPTIONAL, -- Need ON 11 measIdToAddModList MeasIdToAddModList OPTIONAL, -- Need ON 12 -- Other parameters 13 quantityConfig QuantityConfig OPTIONAL, -- Need ON 14 measGapConfig MeasGapConfig OPTIONAL, -- Need ON 15 s-Measure RSRP-Range OPTIONAL, -- Need ON 16 preRegistrationInfoHRPD PreRegistrationInfoHRPD OPTIONAL, -- Need OP 17 speedStatePars CHOICE 18 release NULL, 19 setup SEQUENCE 20 mobilityStateParameters MobilityStateParameters, 21 timeToTrigger-SF SpeedStateScaleFactors 22 23 OPTIONAL, -- Need ON 24 ... 25 26 27 MeasIdToRemoveList ::= SEQUENCE (SIZE (1..maxMeasId)) OF MeasId 28 29 MeasObjectToRemoveList ::= SEQUENCE (SIZE (1..maxObjectId)) OF MeasObjectId 30 31 ReportConfigToRemoveList ::= SEQUENCE (SIZE (1..maxReportConfigId)) OF ReportConfigId 32 33 -- ASN1STOP 34

65


5.1.2.4 ReportConfigEUTRA IE Reference: (3GPP TS 36.331 Section 6.3.5)

Event A1: Serving becomes better than absolute threshold;

Event A2: Serving becomes worse than absolute threshold;

Event A3: Neighbor becomes amount of offset better than serving;

Event A4: Neighbor becomes better than absolute threshold;

Event A5: Serving becomes worse than absolute threshold1 and Neighbor becomes better than another

absolute threshold2. -- ASN1START 1 2 ReportConfigEUTRA ::= SEQUENCE 3 triggerType CHOICE 4 event SEQUENCE 5 eventId CHOICE 6 eventA1 SEQUENCE 7 a1-Threshold ThresholdEUTRA 8 , 9 eventA2 SEQUENCE 10 a2-Threshold ThresholdEUTRA 11 , 12 eventA3 SEQUENCE 13 a3-Offset INTEGER (-30..30), 14 reportOnLeave BOOLEAN 15 , 16 eventA4 SEQUENCE 17 a4-Threshold ThresholdEUTRA 18 , 19 eventA5 SEQUENCE 20 a5-Threshold1 ThresholdEUTRA, 21 a5-Threshold2 ThresholdEUTRA 22 , 23 ... 24 , 25 hysteresis Hysteresis, 26 timeToTrigger TimeToTrigger 27 , 28 periodical SEQUENCE 29 purpose ENUMERATED 30 reportStrongestCells, reportCGI 31 32 , 33 triggerQuantity ENUMERATED rsrp, rsrq, 34 reportQuantity ENUMERATED sameAsTriggerQuantity, both, 35 maxReportCells INTEGER (1..maxCellReport), 36 reportInterval ReportInterval, 37 reportAmount ENUMERATED r1, r2, r4, r8, r16, r32, r64, infinity, 38 ... 39 40 41 ThresholdEUTRA ::= CHOICE 42 threshold-RSRP RSRP-Range, 43 threshold-RSRQ RSRQ-Range 44 45 46 -- ASN1STOP 47

5.1.2.5 Hysteresis IE Reference: (3GPP TS 36.331 Section 6.3.5)

The IE Hysteresis is a parameter used within the entry and leave condition of an event-triggered reporting

condition. The actual value is IE value * 0.5 dB. -- ASN1START 48 49 Hysteresis ::= INTEGER (0..30) 50 51 -- ASN1STOP 52

66


5.1.2.6 Time-To-Trigger IE (Used for s-Measure IE) Reference: (3GPP TS 36.331 Section 6.3.5) -- ASN1START 1 2 TimeToTrigger ::= ENUMERATED 3 ms0, ms40, ms64, ms80, ms100, ms128, ms160, ms256, 4 ms320, ms480, ms512, ms640, ms1024, ms1280, ms2560, 5 ms5120 6 7 -- ASN1STOP 8

5.1.2.7 RSRP-Range IE (Used for s-Measure IE) Reference: (3GPP TS 36.331 Section 6.3.5)

The IE RSRP-Range specifies the value range used in RSRP measurements and thresholds. Use the integer

value for RSRP according to the mapping table in TS 36.133 [16].

Value “0” indicates to disable s-Measure. -- ASN1START 9 10 RSRP-Range ::= INTEGER(0..97) 11 12 -- ASN1STOP 13


The reporting range of RSRP is defined from -140 dBm to -44 dBm with 1 dB resolution.

The mapping of measured quantity is defined in Table 9.1.4-1. The range in the signaling may be larger than

the guaranteed accuracy range.


RSRP_00 RSRP -140 dBm RSRP_01 -140 RSRP < -139 dBm RSRP_02 -139 RSRP < -138 dBm

… … … RSRP_95 -46 RSRP < -45 dBm RSRP_96 -45 RSRP < -44 dBm RSRP_97 -44 RSRP dBm

5.1.2.8 RSRQ-Range IE Reference: (3GPP TS 36.331 Section 6.3.5)

The IE RSRQ-Range specifies the value range used in RSRQ measurements and thresholds. Use the integer

value for RSRQ according to the mapping table in TS 36.133 [16]. -- ASN1START 14 15 RSRQ-Range ::= INTEGER(0..34) 16 17 -- ASN1STOP 18


The reporting range of RSRQ is defined from -19.5 dB to -3 with 0.5 dB resolution. The mapping of measured

quantity is defined in table 9.1.7-1. The range in the signaling may be larger than the guaranteed accuracy

range.


RSRQ_00 RSRQ -19.5 dB RSRQ_01 -19.5 RSRQ < -19 dB RSRQ_02 -19 RSRQ < -18.5 dB

… … … RSRQ_32 -4 RSRQ < -3.5 dB RSRQ_33 -3.5 RSRQ < -3 dB RSRQ_34 -3 RSRQ dB

67


[3] Referring to the RRC Connection Reconfiguration provided in Section 5.3.1, answer the following

questions.

5.1.2.9 Filtering Measurements Prior to Triggering Event A3 Reference: (3GPP TS 36.331 Section 5.5.3.2) 1 5.5.3.2 Layer 3 filtering 2 The UE shall: 3 1> for each measurement quantity that the UE performs measurements according to 5.5.3.1: 4 2> filter the measured result, before using for evaluation of reporting criteria or for 5 measurement reporting, by the following formula: 6 7 8 where 9 Mn is the latest received measurement result from the physical layer; 10 Fn is the updated filtered measurement result, that is used for evaluation of reporting 11

criteria or for measurement reporting; 12 Fn-1 is the old filtered measurement result, where F0 is set to M1 when the first measurement 13

result from the physical layer is received; and 14 a = 1 / 2

(k/4), where k is the filterCoefficent for the corresponding measurement quantity 15

received by the quantityConfig; 16 2> adapt the filter such that the time characteristics of the filter are preserved at different 17 input rates, observing that the filterCoefficent k assumes a sample rate equal to 200 ms; 18 19

a) Refer to reportConfigId 1: Based on the a3-offset, hysteresis and timeToTrigger values, how much

greater must the neighbor cell’s RSRP be, relative to the serving cell’s RSRP, to trigger this A3 event?

(Assume the neighbor’s cellIndividualOffsetEUtran value is 0 dB.)

________

________

b) At what value must the neighbor cell’s RSRP be, relative to the serving cell’s RSRP, to leave Event A3

and cease sending Measurement Reports?

________

________

c) Refer to reportConfigId 4: Based on the a3-offset, hysteresis and timeToTrigger values, how much

greater must the neighbor cell’s RSRP be, relative to the serving cell’s RSRP, to trigger this A3 event?

(Assume the neighbor’s cellIndividualOffsetEUtran value is 0 dB.)

________

________

________

d) Refer to reportConfigId 4: What do you think is the purpose of this set of handover parameters?

________

________

________

nnn MaFaF 1)1(

68


[4] Based on the definition of Layer 3 Filtering, how will the following values of filterCoefficientEUtraRsrp

affect UE measurements?

5.1.3 Handover Trigger – A3 Measurement Reporting

This section will investigate the reporting of Event A3 via the RRC Measurement Report, as well as the

eNodeB’s initial evaluation of the reported cells.

Figure 5: Measurement Reporting

a) Per the spec, what is the sampling rate of UE measurements? ____________

b) k = filterCoefficientEUtraRsrp = 8:

a = 1 / 2(k/4) = ______ Fn = ______% Fn-1 + ______% Current Sample

c) k = filterCoefficientEUtraRsrp = 4:

a = 1 / 2(k/4) = ______ Fn = ______% Fn-1 + ______% Current Sample

69


5.1.3.1 Measurement Report: Reporting Event A3 (eNodeB Cell Trace) FSL00229;16460;8457873;15:28:50:910;UE;ERBS;0;680229-23;282460628;RRC; 1 RRC_MEASUREMENT_REPORT; 2 value UL-DCCH-Message ::= 3 message c1 : measurementReport : 4 criticalExtensions c1 : measurementReport-r8 : 5 measResults 6 measId 1, 7 measResultServCell 8 rsrpResult 30, 9 rsrqResult 23 10 , 11 measResultNeighCells measResultListEUTRA : 12 13 physCellId 489, 14 measResult 15 rsrpResult 35, 16 rsrqResult 30 17 18 19 20 21 22 23 24 25 FSL00229;16460;8457873;15:28:50:910;UE;ERBS;;0; 680229-23;282460628;INTERNAL_EVENT; 26 INTERNAL_EVENT_UE_MOBILITY_EVAL; 27 MOBILITY_TRIGGER: EVENT_VALUE_MEAS_REPORT_A3_BEST_CELL 28 TRIGGERING_MEAS_ID: 1 29 MOBILITY_DECISION: EVENT_VALUE_X2_HO 30 MEAS_ID_BITMAP: Unavailable 31 REDIRECT_RELEASE_INFO: Unavailable 32 RELEASE_WITH_REDIRECT_REASON: Unavailable 33 SPID_VALUE: Invalid 34 SERVING_RSRP: 30 35 SERVING_RSRQ: 23 36 NEIGHBOR_RSRP: 35 37 NEIGHBOR_RSRQ: 30 38

5.1.3.2 Measurement Report Message Reference: (3GPP TS 36.331 Section 6.2.2) 39 -- ASN1START 40 41 MeasurementReport ::= SEQUENCE 42 criticalExtensions CHOICE 43 c1 CHOICE 44 measurementReport-r8 MeasurementReport-r8-IEs, 45 spare7 NULL, 46 spare6 NULL, spare5 NULL, spare4 NULL, 47 spare3 NULL, spare2 NULL, spare1 NULL 48 , 49 criticalExtensionsFuture SEQUENCE 50 51 52 53 MeasurementReport-r8-IEs ::= SEQUENCE 54 measResults MeasResults, 55 nonCriticalExtension SEQUENCE OPTIONAL 56 57 58 -- ASN1STOP 59 60

70


5.1.3.3 MeasResults IE Reference: (3GPP TS 36.331 Section 6.3.5)

The IE MeasResults covers measured results for intra-frequency, inter-frequency and inter-RAT mobility. -- ASN1START 1 2 MeasResults ::= SEQUENCE 3 measId MeasId, 4 measResultServCell SEQUENCE 5 rsrpResult RSRP-Range, 6 rsrqResult RSRQ-Range 7 , 8 measResultNeighCells CHOICE 9 measResultListEUTRA MeasResultListEUTRA, 10 measResultListUTRA MeasResultListUTRA, 11 ... 12 OPTIONAL, 13 ... 14 15 16 MeasResultListEUTRA ::= SEQUENCE (SIZE (1..maxCellReport)) OF MeasResultEUTRA 17 18 MeasResultEUTRA ::= SEQUENCE 19 physCellId PhysCellId, 20 cgi-Info SEQUENCE 21 cellGlobalId CellGlobalIdEUTRA, 22 trackingAreaCode TrackingAreaCode, 23 plmn-IdentityList PLMN-IdentityList2 OPTIONAL 24 OPTIONAL, 25 measResult SEQUENCE 26 rsrpResult RSRP-Range OPTIONAL, 27 rsrqResult RSRQ-Range OPTIONAL, 28 ... 29 30 31 32 MeasResultListUTRA ::= SEQUENCE (SIZE (1..maxCellReport)) OF MeasResultUTRA 33 34 MeasResultUTRA ::= SEQUENCE 35 physCellId CHOICE 36 fdd PhysCellIdUTRA-FDD, 37 tdd PhysCellIdUTRA-TDD 38 , 39 cgi-Info SEQUENCE 40 cellGlobalId CellGlobalIdUTRA, 41 locationAreaCode BIT STRING (SIZE (16)) OPTIONAL, 42 routingAreaCode BIT STRING (SIZE (8)) OPTIONAL, 43 plmn-IdentityList PLMN-IdentityList2 OPTIONAL 44 OPTIONAL, 45 measResult SEQUENCE 46 utra-RSCP INTEGER (-5..91) OPTIONAL, 47 utra-EcN0 INTEGER (0..49) OPTIONAL, 48 ... 49 50 51 52 PLMN-IdentityList2 ::= SEQUENCE (SIZE (1..5)) OF PLMN-Identity 53 54 -- ASN1STOP 55 56

71


[5] Answer the following questions based on the Measurement Report message provided or the local

market example Exercise5.5.txt located on the class jump drive (ask the instructor).

5.1.3.4 eNodeB Evaluation of Event A3 Measurement Report Upon reception of the Event A3 Measurement Report, the vendor eNodeB will evaluate its contents prior to

moving on to the Handover Preparation phase.

The following parameters are part of the EUtranCellRelation Managed Object and are configurable at the cell

level per neighbor relation. These parameters can be used to control Handover to neighbor cells. Only target

cells that are defined as “EUtranCellRelations” (i.e. neighbors) of a cell can trigger a handover. A3

Measurement Reports regarding missing neighbors will be evaluated by the source cell; however they will not

result in a Handover Request. Vendor Parameter Name Parameter Description

isHoAllowed If set to True, the reported neighbor will be evaluated for Handover and Idle Mode

Reselection, else the Event A3 Measurement Report for this neighbor will be ignored.

5.1.4 Handover Preparation – X2 and S1 Signaling

This section will explore both the successful and unsuccessful X2 signaling scenarios, related to intra-

frequency handover. In addition, the S1 signaling call flow (when X2 is unavailable) will be discussed.

a) How can you tell this Measurement Report is related to an Event A3?

b) Based on this Measurement Report, provide the following information:

Serving Cell: PCI: n/a RSRP: dBm RSRQ: dB

Target Cell#1: PCI: RSRP: dBm RSRQ: dB

Target Cell#2: PCI: RSRP: dBm RSRQ: dB

c) Access the neighbor list of the Serving cell. Does the Serving cell have an X2 built with the reported

neighbor? If yes, what is the ECGI & the IP address of the reported neighbor?

d) Based on this internal report, what decision does the eNodeB make based on the evaluation of the

received Measurement Report?

e) What would the eNodeB do if the UE’s reported PCI was not in the neighbor list of the eNodeB?

72


5.1.4.1 Successful Handover Preparation - X2 Signaling The following illustrates the X2 Control Plane signaling for the Handover Request by the Source eNodeB and

the positive response from the Target eNodeB.

Figure 6: Handover Preparation Success – X2

73


5.1.4.2 Handover Request/Handover Request Ack – X2 Message (eNodeB Cell Trace) FSL00229;16471;8457873;15:28:51:771;ERBS;ERBS;0;680229-23;282460628;X2AP; 1 X2_HANDOVER_REQUEST; 2 value X2AP-PDU ::= initiatingMessage : 3 procedureCode 0, 4 criticality reject, 5 value HandoverRequest : 6 protocolIEs 7 8 id 10, 9 criticality reject, 10 value UE-X2AP-ID : 2464 11 , 12 13 id 5, 14 criticality ignore, 15 value Cause : radioNetwork : handover-desirable-for-radio-reasons 16 , 17 18 id 11, 19 criticality reject, 20 value ECGI : 21 pLMN-Identity '134001'H, 22 eUTRANcellIdentifier '10100110 00010010 01010001 0000'B 23 24 , 25 26 id 23, 27 criticality reject, 28 value GUMMEI : 29 gU-Group-ID 30 pLMN-Identity '134001'H, 31 mME-Group-ID 'FF10'H 32 , 33 mMME-Code '09'H 34 35 , 36 37 id 14, 38 criticality reject, 39 value UE-ContextInformation : 40 mME-UE-S1AP-ID 282460628, 41 uESecurityCapabilities 42 encryptionAlgorithms '11000000 00000000'B, 43 integrityProtectionAlgorithms '11000000 00000000'B 44 , 45 aS-SecurityInformation 46 key-eNodeB-star '11111111 11111111 11111111 11111111 111'B --truncated--, 47 nextHopChainingCount 3 48 , 49 uEaggregateMaximumBitRate 50 uEaggregateMaximumBitRateDownlink 70000000, 51 uEaggregateMaximumBitRateUplink 25000000 52 , 53 e-RABs-ToBeSetup-List 54 55 id 4, 56 criticality ignore, 57 value E-RABs-ToBeSetup-Item : 58 e-RAB-ID 5, 59 e-RAB-Level-QoS-Parameters 60 qCI 8, 61 allocationAndRetentionPriority 62

74


priorityLevel 10, 1 pre-emptionCapability shall-not-trigger-pre-emption, 2 pre-emptionVulnerability pre-emptable 3 4 , 5 dL-Forwarding dL-forwardingProposed, 6 uL-GTPtunnelEndpoint 7 transportLayerAddress '10100110 10010011 01111000 11101110'B, 8 gTP-TEID 'C2F4357A'H 9 10 11 12 , 13 rRC-Context '0A1023C520000304184200E1F8FFF0FC7FF3F1FFDF8……'H --truncated--, 14 handoverRestrictionList 15 servingPLMN '134001'H, 16 forbiddenInterRATs cdma2000 17 18 19 , 20 21 id 15, 22 criticality ignore, 23 value UE-HistoryInformation : 24 e-UTRAN-Cell : 25 global-Cell-ID 26 pLMN-Identity '134001'H, 27 eUTRANcellIdentifier '10100110 00010010 01010001 0111'B 28 , 29 cellType 30 cell-Size verysmall 31 , 32 time-UE-StayedInCell 2 33 34 35 36 37 38 39 40 41 FSL00229;16472;8457873;15:28:51:795;ERBS;ERBS;0;680229-23;282460628;X2AP; 42 X2_HANDOVER_REQUEST_ACKNOWLEDGE; 43 value X2AP-PDU ::= successfulOutcome : 44 procedureCode 0, 45 criticality reject, 46 value HandoverRequestAcknowledge : 47 protocolIEs 48 49 id 10, 50 criticality ignore, 51 value UE-X2AP-ID : 2464 52 , 53 54 id 9, 55 criticality ignore, 56 value UE-X2AP-ID : 2469 57 , 58 59 id 1, 60 criticality ignore, 61 value E-RABs-Admitted-List : 62 63

75


id 0, 1 criticality ignore, 2 value E-RABs-Admitted-Item : 3 e-RAB-ID 5, 4 dL-GTP-TunnelEndpoint 5 transportLayerAddress '00000000 00000000 00000000 00000000'B, 6 gTP-TEID '800008E1'H 7 8 9 10 11 , 12 13 id 12, 14 criticality ignore, 15 value TargeteNBtoSource-eNBTransparentContainer : 16 '020900D9500200900110C8400443239D616941828B5DBFC7CAD3BE182B014E4000'H -- truncated -- 17 18 19 20 21 22 23 FSL00229;16473;8457873;15:28:51:795;ERBS;;0;680229-23;282460628;INTERNAL_PROC; 24 INTERNAL_PROC_HO_PREP_X2_OUT; 25 HO_SOURCE_OR_TARGET_TYPE: EVENT_VALUE_LTE_INTRA_FREQ 26 HO_TARGET_SELECTION_TYPE: EVENT_VALUE_MEAS_BASED 27 PROC_HO_PREP_OUT_ATTEMPT_CAUSE: EVENT_A3_REPORTED_BY_UE 28 PROC_HO_PREP_OUT_RESULT: SUCCESSFUL 29 HO_TYPE: INTRA_ENB 30 HO_OUT_PREP_ERAB_REQ_BITMAP: 32 31 HO_OUT_PREP_ERAB_FAIL_BITMAP: 0 32 3GPP_CAUSE_GROUP: Unavailable 33 3GPP_CAUSE: Unavailable 34 HO_PREP_QCI: Unavailable 35 HO_PREP_QCI: Unavailable 36 HO_PREP_QCI: Unavailable 37 HO_PREP_QCI: Unavailable 38 HO_PREP_QCI: Unavailable 39 HO_PREP_QCI: 8 40 HO_PREP_QCI: Unavailable 41 HO_PREP_QCI: Unavailable 42 HO_PREP_QCI: Unavailable 43 HO_PREP_QCI: Unavailable 44 HO_PREP_QCI: Unavailable 45 HO_PREP_QCI: Unavailable 46 HO_PREP_QCI: Unavailable 47 HO_PREP_QCI: Unavailable 48 HO_PREP_QCI: Unavailable 49 HO_PREP_QCI: Unavailable 50 TIMESTAMP_START_HOUR: 15 51 TIMESTAMP_START_MINUTE: 28 52 TIMESTAMP_START_SECOND: 51 53 TIMESTAMP_START_MILLISEC: 770 54 TIMESTAMP_STOP_HOUR: 15 55 TIMESTAMP_STOP_MINUTE: 28 56 TIMESTAMP_STOP_SECOND: 51 57 TIMESTAMP_STOP_MILLISEC: 795 58 NEIGHBOR_CGI: PLMNID : 310-410, ENBID : 680229, CELLID : 16 59

76


5.1.4.3 X2 Handover Request Message Reference: (3GPP TS 36.423 Section 9.3.4) 1 HandoverRequest ::= SEQUENCE 2 protocolIEs ProtocolIE-Container HandoverRequest-IEs, 3 ... 4 5 6 HandoverRequest-IEs X2AP-PROTOCOL-IES ::= 7 ID id-Old-eNB-UE-X2AP-ID CRITICALITY reject TYPE UE-X2AP-ID 8 PRESENCE mandatory | 9 ID id-Cause CRITICALITY ignore TYPE Cause 10 PRESENCE mandatory | 11 ID id-TargetCell-ID CRITICALITY reject TYPE ECGI 12 PRESENCE mandatory | 13 ID id-GUMMEI-ID CRITICALITY reject TYPE GUMMEI 14 PRESENCE mandatory | 15 ID id-UE-ContextInformation CRITICALITY reject TYPE UE-ContextInformation 16 PRESENCE mandatory | 17 ID id-UE-HistoryInformation CRITICALITY ignore TYPE UE-HistoryInformation 18 PRESENCE mandatory | 19 ID id-TraceActivation CRITICALITY ignore TYPE TraceActivation 20 PRESENCE optional | 21 ID id-SRVCCOperationPossible CRITICALITY ignore TYPE SRVCCOperationPossible 22 PRESENCE optional , 23 ... 24 25 26 UE-ContextInformation ::= SEQUENCE 27 mME-UE-S1AP-ID UE-S1AP-ID, 28 uESecurityCapabilities UESecurityCapabilities, 29 aS-SecurityInformation AS-SecurityInformation, 30 uEaggregateMaximumBitRate UEAggregateMaximumBitRate, 31 subscriberProfileIDforRFP SubscriberProfileIDforRFP OPTIONAL, 32 e-RABs-ToBeSetup-List E-RABs-ToBeSetup-List, 33 rRC-Context RRC-Context, 34 handoverRestrictionList HandoverRestrictionList OPTIONAL, 35 locationReportingInformation LocationReportingInformation OPTIONAL, 36 iE-Extensions ProtocolExtensionContainer UE-ContextInformation-37 ExtIEs OPTIONAL, 38 ... 39 40 41 UE-ContextInformation-ExtIEs X2AP-PROTOCOL-EXTENSION ::= 42 ... 43 44 45 E-RABs-ToBeSetup-List ::= SEQUENCE (SIZE(1..maxnoofBearers)) OF ProtocolIE-Single-Container E-46 RABs-ToBeSetup-ItemIEs 47 48 E-RABs-ToBeSetup-ItemIEs X2AP-PROTOCOL-IES ::= 49 ID id-E-RABs-ToBeSetup-Item CRITICALITY ignore TYPE E-RABs-ToBeSetup-Item PRESENCE 50 mandatory , 51 ... 52 53 54 E-RABs-ToBeSetup-Item ::= SEQUENCE 55 e-RAB-ID E-RAB-ID, 56 e-RAB-Level-QoS-Parameters E-RAB-Level-QoS-Parameters, 57 dL-Forwarding DL-Forwarding 58 OPTIONAL, 59 uL-GTPtunnelEndpoint GTPtunnelEndpoint, 60 iE-Extensions ProtocolExtensionContainer E-RABs-ToBeSetup-ItemExtIEs 61 OPTIONAL, 62 ... 63 64 65 E-RABs-ToBeSetup-ItemExtIEs X2AP-PROTOCOL-EXTENSION ::= 66 ... 67 68

77


5.1.4.4 X2 Handover Request Acknowledge Message Reference: (3GPP TS 36.423 Section 9.3.4) HandoverRequestAcknowledge ::= SEQUENCE 1 protocolIEs ProtocolIE-Container HandoverRequestAcknowledge-2 IEs, 3 ... 4 5 6 HandoverRequestAcknowledge-IEs X2AP-PROTOCOL-IES ::= 7 ID id-Old-eNB-UE-X2AP-ID CRITICALITY ignore TYPE UE-X2AP-ID 8 PRESENCE mandatory | 9 ID id-New-eNB-UE-X2AP-ID CRITICALITY ignore TYPE UE-X2AP-ID 10 PRESENCE mandatory | 11 ID id-E-RABs-Admitted-List CRITICALITY ignore TYPE E-RABs-Admitted-12 List PRESENCE mandatory | 13 ID id-E-RABs-NotAdmitted-List CRITICALITY ignore TYPE E-RAB-List 14 PRESENCE optional | 15 ID id-TargeteNBtoSource-eNBTransparentContainer CRITICALITY ignore TYPE 16 TargeteNBtoSource-eNBTransparentContainer PRESENCE mandatory | 17 ID id-CriticalityDiagnostics CRITICALITY ignore TYPE 18 CriticalityDiagnostics PRESENCE optional , 19 ... 20 21 22 E-RABs-Admitted-List ::= SEQUENCE (SIZE (1..maxnoofBearers)) OF ProtocolIE-Single-23 Container E-RABs-Admitted-ItemIEs 24 25 E-RABs-Admitted-ItemIEs X2AP-PROTOCOL-IES ::= 26 ID id-E-RABs-Admitted-Item CRITICALITY ignore TYPE E-RABs-Admitted-Item PRESENCE 27 mandatory 28 29 30 E-RABs-Admitted-Item ::= SEQUENCE 31 e-RAB-ID E-RAB-ID, 32 uL-GTP-TunnelEndpoint GTPtunnelEndpoint OPTIONAL, 33 dL-GTP-TunnelEndpoint GTPtunnelEndpoint OPTIONAL, 34 iE-Extensions ProtocolExtensionContainer E-RABs-Admitted-Item-ExtIEs 35 OPTIONAL, 36 ... 37 38 39 E-RABs-Admitted-Item-ExtIEs X2AP-PROTOCOL-EXTENSION ::= 40 ... 41 42

5.1.4.5 ECGI – The E-UTRAN Cell Global Identifier Reference: (3GPP TS 36.423 Section 9.3.5) ECGI ::= SEQUENCE 43 pLMN-Identity PLMN-Identity, 44 eUTRANcellIdentifier EUTRANCellIdentifier, 45 iE-Extensions ProtocolExtensionContainer ECGI-ExtIEs OPTIONAL, 46 ... 47 48 49 EUTRANCellIdentifier ::= BIT STRING (SIZE (28)) 50

Based on 3GPP TS 36.423 Section 9.3.5, the eNB ID and cell can be obtained from the ECGI as follows:

The eNB ID is the 2O left-most bits of the left-most bits of the value of the 28-bit E-UTRAN Cell Identifier IE contained in the ECGI IE. Convert these 20 binary bits to decimal to obtain the eNB ID. The remaining eight remaining right-most bits identify the Cell ID. Convert these eight binary bits to decimal to obtain the Cell ID.

78


5.1.4.6 Unsuccessful Handover Preparation - X2 Signaling The following shows the X2 Control Plane signaling for a couple of Handover failure scenarios. One scenario

occurs when the Target eNodeB responds to the Source eNodeB’s Handover request with a Handover

Preparation Failure. The other scenario occurs when there is never a response to the Source eNodeB’s

Handover request. In this case, the Source eNodeB TRELOCprep timer will expire and the Source eNodeB will

send a Handover Cancel message to the Target eNodeB.

Figure 7: Handover Preparation Failure – X2

Figure 8: Handover Cancel – X2

79


5.1.4.7 X2 Handover Preparation Failure Message Reference: (3GPP TS 36.423 Section 9.3.4) HandoverPreparationFailure ::= SEQUENCE 1 protocolIEs ProtocolIE-Container HandoverPreparationFailure-2 IEs, 3 ... 4 5 6 HandoverPreparationFailure-IEs X2AP-PROTOCOL-IES ::= 7 ID id-Old-eNB-UE-X2AP-ID CRITICALITY ignore TYPE UE-X2AP-ID PRESENCE 8 mandatory | 9 ID id-Cause CRITICALITY ignore TYPE Cause PRESENCE 10 mandatory | 11 ID id-CriticalityDiagnostics CRITICALITY ignore TYPE CriticalityDiagnostics PRESENCE 12 optional , 13 14 ... 15 16

5.1.4.8 X2 Handover Cancel Reference: (3GPP TS 36.423 Section 9.3.5) HandoverCancel ::= SEQUENCE 17 protocolIEs ProtocolIE-Container HandoverCancel-IEs, 18 ... 19 20 21 HandoverCancel-IEs X2AP-PROTOCOL-IES ::= 22 ID id-Old-eNB-UE-X2AP-ID CRITICALITY reject TYPE UE-X2AP-ID PRESENCE 23 mandatory | 24 ID id-New-eNB-UE-X2AP-ID CRITICALITY ignore TYPE UE-X2AP-ID PRESENCE 25 optional | 26 ID id-Cause CRITICALITY ignore TYPE Cause PRESENCE 27 mandatory , 28 ... 29 30

5.1.4.9 X2 Signaling Causes Reference: (3GPP TS 36.423 Section 9.3.5) Cause ::= CHOICE 31 radioNetwork CauseRadioNetwork, 32 transport CauseTransport, 33 protocol CauseProtocol, 34 misc CauseMisc, 35 ... 36 37 38 CauseMisc ::= ENUMERATED 39 control-processing-overload, 40 hardware-failure, 41 om-intervention, 42 not-enough-user-plane-processing-resources, 43 unspecified, 44 ... 45 46 47 CauseProtocol ::= ENUMERATED 48 transfer-syntax-error, 49 abstract-syntax-error-reject, 50 abstract-syntax-error-ignore-and-notify, 51 message-not-compatible-with-receiver-state, 52 semantic-error, 53 unspecified, 54 abstract-syntax-error-falsely-constructed-message, 55 ... 56 57 58 CauseRadioNetwork ::= ENUMERATED 59

80


handover-desirable-for-radio-reasons, 1 time-critical-handover, 2 resource-optimisation-handover, 3 reduce-load-in-serving-cell, 4 partial-handover, 5 unknown-new-eNB-UE-X2AP-ID, 6 unknown-old-eNB-UE-X2AP-ID, 7 unknown-pair-of-UE-X2AP-ID, 8 ho-target-not-allowed, 9 tx2relocoverall-expiry, 10 trelocprep-expiry, 11 cell-not-available, 12 no-radio-resources-available-in-target-cell, 13 invalid-MME-GroupID, 14 unknown-MME-Code, 15 encryption-and-or-integrity-protection-algorithms-not-supported, 16 reportCharacteristicsEmpty, 17 noReportPeriodicity, 18 existingMeasurementID, 19 unknown-eNB-Measurement-ID, 20 measurement-temporarily-not-available, 21 unspecified, 22 ... 23 24 25 26 CauseTransport ::= ENUMERATED 27 transport-resource-unavailable, 28 unspecified, 29 ... 30 31

81


5.1.4.10 Successful Handover Preparation – S1 Signaling The following illustrates the S1 Control Plane signaling for the Handover Request by the Source eNodeB and

the positive response from the Target eNodeB.

Figure 9: Handover Preparation Success – S1

82


5.1.4.11 S1 Handover Messages (eNodeB Cell Trace) Outbound S1 Handover Messages: 1 2 DXL00611;20773;18505215;14:56:51:070;ERBS;MME;Unavailable;520611-16;17145801;S1AP; 3 S1_HANDOVER_REQUIRED; (Serving Cell to the MME) 4 5 value S1AP-PDU ::= initiatingMessage : 6 procedureCode 0, 7 criticality reject, 8 value HandoverRequired : 9 protocolIEs 10 11 id 0, 12 criticality reject, 13 value MME-UE-S1AP-ID : 17145801 14 , 15 16 id 8, 17 criticality reject, 18 value ENB-UE-S1AP-ID : 1113 19 , 20 21 id 1, 22 criticality reject, 23 value HandoverType : intralte 24 , 25 26 id 2, 27 criticality ignore, 28 value Cause : radioNetwork : s1-intra-system-handover-triggered 29 , 30 31 id 4, 32 criticality reject, 33 value TargetID : targeteNB-ID : 34 global-ENB-ID 35 pLMNidentity '134001'H, 36 eNB-ID macroENB-ID : '01111110 11110110 1111'B 37 , 38 selected-TAI 39 pLMNidentity '134001'H, 40 tAC '6A07'H 41 42 43 , 44 45 id 104, 46 criticality reject, 47 value Source-ToTarget-TransparentContainer : 48 '00809E0E1017812000010C801838DFE0E37F5E0DD88088100240CA74A815F800000B4A'H -- truncated 49 -- 50 51 52 53 54 55 56 DXL00611;20774;18505215;14:56:51:157;MME;ERBS;Unavailable;520611-16;17145801;S1AP; 57 S1_HANDOVER_COMMAND; (MME to the Serving Cell) 58 59 value S1AP-PDU ::= successfulOutcome : 60 procedureCode 0, 61 criticality reject, 62

83


value HandoverCommand : 1 protocolIEs 2 3 id 0, 4 criticality reject, 5 value MME-UE-S1AP-ID : 17145801 6 , 7 8 id 8, 9 criticality reject, 10 value ENB-UE-S1AP-ID : 1113 11 , 12 13 id 1, 14 criticality reject, 15 value HandoverType : intralte 16 , 17 18 id 123, 19 criticality reject, 20 value Target-ToSource-TransparentContainer : 21 '002F01690058C40182BE21BFC7AACABB001B015040040080200805FA955EEA0A2C5C4C'H -- truncated 22 -- 23 24 25 26 27 28 DXL00611;20775;18505215;14:56:51:157;ERBS;;Unavailable;520611-29 16;17145801;INTERNAL_PROC;INTERNAL_PROC_HO_PREP_S1_OUT; 30 31 HO_SOURCE_OR_TARGET_TYPE: EVENT_VALUE_LTE_INTRA_FREQ 32 HO_TARGET_SELECTION_TYPE: EVENT_VALUE_MEAS_BASED 33 NEIGHBOR_CGI: PLMNID : 310-410, ENBID : 520047, CELLID : 16 34 PROC_HO_PREP_OUT_ATTEMPT_CAUSE: EVENT_A3_REPORTED_BY_UE 35 PROC_HO_PREP_OUT_RESULT: SUCCESSFUL 36 HO_OUT_PREP_ERAB_REQ_BITMAP: 32 37 HO_OUT_PREP_ERAB_FAIL_BITMAP: 0 38 TIMESTAMP_START_HOUR: 14 39 TIMESTAMP_START_MINUTE: 56 40 TIMESTAMP_START_SECOND: 51 41 TIMESTAMP_START_MILLISEC: 69 42 TIMESTAMP_STOP_HOUR: 14 43 TIMESTAMP_STOP_MINUTE: 56 44 TIMESTAMP_STOP_SECOND: 51 45 TIMESTAMP_STOP_MILLISEC: 157 46 47 48 Inbound S1 Handover Messages: 49 50 DXL00611;20576;18505215;14:56:49:947;MME;ERBS;Unavailable;520611-16;17145801;S1AP; 51 S1_HANDOVER_REQUEST; (MME to the Target Cell) 52 53 value S1AP-PDU ::= initiatingMessage : 54 procedureCode 1, 55 criticality reject, 56 value HandoverRequest : 57 protocolIEs 58 59 id 0, 60 criticality reject, 61 value MME-UE-S1AP-ID : 17145801 62 , 63

84


1 id 1, 2 criticality reject, 3 value HandoverType : intralte 4 , 5 6 id 2, 7 criticality ignore, 8 value Cause : radioNetwork : s1-intra-system-handover-triggered 9 , 10 11 id 66, 12 criticality reject, 13 value UEAggregateMaximumBitrate : 14 uEaggregateMaximumBitRateDL 70000000, 15 uEaggregateMaximumBitRateUL 25000000 16 17 , 18 19 id 53, 20 criticality reject, 21 value E-RABToBeSetupListHOReq : 22 23 id 27, 24 criticality reject, 25 value E-RABToBeSetupItemHOReq : 26 e-RAB-ID 5, 27 transportLayerAddress '10100110 10010011 01001000 11101001'B, 28 gTP-TEID '0510D659'H, 29 e-RABlevelQosParameters 30 qCI 8, 31 allocationRetentionPriority 32 priorityLevel 10, 33 pre-emptionCapability shall-not-trigger-pre-emption, 34 pre-emptionVulnerability pre-emptable 35 36 37 38 39 40 , 41 42 id 104, 43 criticality reject, 44 value Source-ToTarget-TransparentContainer : 45 '00809E0E1017812000010C801838DFE0E37F5E0DD88088100240CA74A815F800000B4A'H -- truncated 46 -- 47 , 48 49 id 107, 50 criticality reject, 51 value UESecurityCapabilities : 52 encryptionAlgorithms '11000000 00000000'B, 53 integrityProtectionAlgorithms '11000000 00000000'B 54 55 , 56 57 id 40, 58 criticality reject, 59 value SecurityContext : 60 nextHopChainingCount 4, 61 nextHopParameter '11111111 11111111 11111111 11111111 111'B -- truncated -- 62 63

85


1 2 3 4 5 6 DXL00611;20579;18505215;14:56:49:966;ERBS;MME;Unavailable;520611-16;17145801;S1AP; 7 S1_HANDOVER_REQUEST_ACKNOWLEDGE; (Target Cell to the MME) 8 9 value S1AP-PDU ::= successfulOutcome : 10 procedureCode 1, 11 criticality reject, 12 value HandoverRequestAcknowledge : 13 protocolIEs 14 15 id 0, 16 criticality ignore, 17 value MME-UE-S1AP-ID : 17145801 18 , 19 20 id 8, 21 criticality ignore, 22 value ENB-UE-S1AP-ID : 1113 23 , 24 25 id 18, 26 criticality ignore, 27 value E-RABAdmittedList : 28 29 id 20, 30 criticality ignore, 31 value E-RABAdmittedItem : 32 e-RAB-ID 5, 33 transportLayerAddress '10111000 10001011 00011001 00100110'B, 34 gTP-TEID '3E5AFA75'H 35 36 37 38 , 39 40 id 123, 41 criticality reject, 42 value Target-ToSource-TransparentContainer : 43 '002F01690058D1E182BC12BFC7AACABB001B015040040080200805FA955EEA0A2C5C4C'H -- truncated 44 -- 45 46 47 48 49 50 51 DXL00611;20580;18505215;14:56:49:966;ERBS;;Unavailable;520611-52 16;17145801;INTERNAL_PROC;INTERNAL_PROC_HO_PREP_S1_IN; 53 54 HO_SOURCE_OR_TARGET_TYPE: EVENT_VALUE_LTE_INTRA_FREQ 55 NEIGHBOR_CGI: PLMNID : 310-410, ENBID : 520047, CELLID : 16 56 PROC_HO_PREP_IN_RESULT: SUCCESSFUL 57 TIMESTAMP_START_HOUR: 14 58 TIMESTAMP_START_MINUTE: 56 59 TIMESTAMP_START_SECOND: 49 60 TIMESTAMP_START_MILLISEC: 948 61 TIMESTAMP_STOP_HOUR: 14 62 TIMESTAMP_STOP_MINUTE: 56 63

86


TIMESTAMP_STOP_SECOND: 49 1 TIMESTAMP_STOP_MILLISEC: 966 2

5.1.4.12 Unsuccessful Handover Preparation – S1 Signaling The following shows the S1 Control Plane signaling for a couple of Handover failure scenarios. One scenario

occurs when the Target eNodeB responds to the Source eNodeB’s Handover Request with a Handover

Preparation Failure. The other scenario occurs when there is never a response to Source eNodeB’s Handover

Request. In this case, the Source eNodeB TRELOCprep timer will expire and the Source eNodeB will send a

Handover Cancel message to the Target eNodeB.

Figure 10: Handover Preparation Failure – S1

87


Figure 11: Handover Cancel - S1

5.1.4.13 Resolving Handover Preparation Failure As illustrated in the previous sections, the X2 or S1 Handover Request can fail due to numerous reasons. This

can include, but is not limited to: a lack of resources or license issues in the target eNodeB, or no response

(positive or negative) to the Handover Request/Required message. How the Vendor eNodeB responds to these

scenarios is dependent on the reported neighbor candidates and the configuration of the following parameter

(which is part of the EUtranCell Managed Object). Vendor Parameter Name Vendor Configurable Range Parameter Description

minBestCellHoAttempts (1, 2, 3, …9, 10) If an Event A3 Measurement Report contains multiple

neighbor candidates, this parameter will define how

many attempts the eNodeB will try to handover to the

best candidate before the next best candidate is

attempted. If only a single candidate is reported, that cell

will be attempted repeatedly as long as the triggering

event is valid.

If the Measurement Report that triggered the handover attempt contains multiple handover candidates, the

best cell will be attempted minBestCellHoAttempts times before the second best cell is attempted. If only a

single cell is reported in the Measurement Report message, the best cell will be attempted repeatedly as long

as the eNodeB receives a valid periodical or new Measurement Report message. The following events will

indicate a failed handover attempt:

The reception of a Handover Preparation Failure message (either from S1 or X2 handover attempt)

Expiration of the relocation timer trelocprep (X2) or tS1relocprep (S1).

If the handover attempt fails, either the best candidate cell, or the next best candidate cell will be attempted

depending upon the value of the parameter minBestCellHoAttempts, the number of previous attempts, and the

last received Measurement Report message.

88


5.1.4.14 eNodeB Event A3 Handover Counters In this section, eNodeB Event A3 handover-related counters will be discussed.

Vendor Counter Name Counter Description

pmBestCellEvalReport Pegged upon reception of an Event A3 Measurement Report that results in an evaluation

by the eNodeB

pmHoPrepAttLteIntraF Pegged during the preparation phase of an intra frequency handover when the source

eNodeB send either an X2 Handover Request message, or a S1 Handover Required

message. This counter pegs on a per-neighbour basis.

pmHoPrepSuccLteIntraF Pegged during the preparation phase of an intra frequency handover when the source

eNodeB receives either an X2 Handover Request Ack message, or a S1 Handover

Command message, indicating the target eNodeB had reserved resources for the UE’s

pending handover. This counter pegs on a per-neighbour basis.

pmHoPrepRejInLicConnUsers Pegged during the preparation phase of an intra frequency handover when the target

eNodeB sends a Handover Preparation Failure message due to the number of connected

users in the cell exceeding the licensed amount. Pegged in target cell.

pmHoPrepRejInLicMob Pegged during the preparation phase of an intra frequency handover when the target

eNodeB sends a Handover Preparation Failure message due to no license for intra

frequency handover. Pegged in target cell.

Based on analysis of Vendor eNodeB cell traces and counters, the counter pmBestCellEvalReport is

incremented each time an INTERNAL_EVENT_BEST_CELL_EVAL report is invoked in response to the reception

of an Event A3 Measurement Report is received. This includes Event A3 Measurement Reports for missing

neighbors.

If an Event A3 Measurement Report is received, and an INTERNAL_EVENT_BEST_CELL_EVAL report is not

invoked (i.e., the Measurement Report is ignored), this counter is not pegged. The following are examples of

events that will not invoke an INTERNAL_EVENT_BEST_CELL_EVAL report:

The reception of an Event A3 Measurement Report for a UE that is already in the process of

performing an intra-frequency handover.

The reception of an Event A3 Measurement Report for a UE that is in the process of having its UE

Context within the cell released.

89


[6] Answer the following questions.

a) Refer to the eNodeB Cell Trace provided in Section 5.5.2, or use the local market example (e.g.,

Exercise5.6.txt located on the class jump drive): In the X2 Handover Request Acknowledge Message, how

many EPS Bearers requested by the Source Cell were admitted by the Target Cell?

__________

b) Open the counter file Exercise5.6.xlsx, which is provided on the Award Solutions jump drive. Consider rows

with pmHoPrepAttLteIntraF_sum >= 500; this will remove statistically insignificant data. Sort on the HO Prep

Fail % column and provide 3 cells with the highest % of handover prep failures:

• Cell1: _______________ HO Prep Fail %: __________________________

• Cell2: ______________ HO Prep Fail %: __________________________

• Cell3: _______________ HO Prep Fail %: __________________________

c) Why is the failure rate high on these cells? Investigate by looking at the per-neighbor counts of Handover Prep

Failures (refer to Handover_Performance_Per_Neighbor.xlsx located on the class jump drive) and RMAP.

• Neighbors of Cell 1 with highest number of failures: _____________________________________________



d) What are the causes of the handover prep failures in the above cells?

• Cell1: __________________________________________________________________________

• Cell2: __________________________________________________________________________

• Cell3: __________________________________________________________________________

e) In general, what are the likely issues that cause an increase in the number of handover prep failures on a cell?

__________

__________

__________

90


5.1.5 Handover Execution

This section will investigate RRC signaling during the final phase of intra-frequency handover. It is during this

phase that the Source eNodeB instructs the UE to make a hard handover to the Target eNodeB. In addition,

the UE must use the Random Access Procedure to access the target cell.

Figure 12: Handover Execution

91


5.1.5.1 RRC Connection Reconfiguration: Intra-Frequency Handover Command (UE Log Messages) FSL00229;16474;8457873;15:28:51:796;ERBS;UE;0;680229-23;282460628;RRC; 1 RRC_RRC_CONNECTION_RECONFIGURATION; 2 value DL-DCCH-Message ::= 3 message c1 : rrcConnectionReconfiguration : 4 rrc-TransactionIdentifier 0, 5 criticalExtensions c1 : rrcConnectionReconfiguration-r8 : 6 mobilityControlInfo 7 targetPhysCellId 489, 8 carrierBandwidth 9 dl-Bandwidth n50 10 , 11 additionalSpectrumEmission 1, 12 t304 ms1000, 13 newUE-Identity '00011001 10100100'B, 14 radioResourceConfigCommon 15 rach-ConfigCommon 16 preambleInfo 17 numberOfRA-Preambles n64 18 , 19 powerRampingParameters 20 powerRampingStep dB4, 21 preambleInitialReceivedTargetPower dBm-110 22 , 23 ra-SupervisionInfo 24 preambleTransMax n10, 25 ra-ResponseWindowSize sf6, 26 mac-ContentionResolutionTimer sf64 27 , 28 maxHARQ-Msg3Tx 4 29 , 30 prach-Config 31 rootSequenceIndex 780, 32 prach-ConfigInfo 33 prach-ConfigIndex 5, 34 highSpeedFlag FALSE, 35 zeroCorrelationZoneConfig 12, 36 prach-FreqOffset 2 37 38 , 39 pdsch-ConfigCommon 40 referenceSignalPower 18, 41 p-b 1 42 , 43 pusch-ConfigCommon 44 pusch-ConfigBasic 45 n-SB 1, 46 hoppingMode interSubFrame, 47 pusch-HoppingOffset 0, 48 enable64QAM FALSE 49 , 50 ul-ReferenceSignalsPUSCH 51 groupHoppingEnabled TRUE, 52 groupAssignmentPUSCH 0, 53 sequenceHoppingEnabled FALSE, 54 cyclicShift 0 55 56 , 57 phich-Config 58 phich-Duration normal, 59 phich-Resource one 60 , 61 pucch-ConfigCommon 62

92


deltaPUCCH-Shift ds1, 1 nRB-CQI 1, 2 nCS-AN 0, 3 n1PUCCH-AN 59 4 , 5 soundingRS-UL-ConfigCommon setup : 6 srs-BandwidthConfig bw0, 7 srs-SubframeConfig sc3, 8 ackNackSRS-SimultaneousTransmission TRUE 9 , 10 uplinkPowerControlCommon 11 p0-NominalPUSCH -100, 12 alpha al1, 13 p0-NominalPUCCH -116, 14 deltaFList-PUCCH 15 deltaF-PUCCH-Format1 deltaF0, 16 deltaF-PUCCH-Format1b deltaF3, 17 deltaF-PUCCH-Format2 deltaF0, 18 deltaF-PUCCH-Format2a deltaF0, 19 deltaF-PUCCH-Format2b deltaF0 20 , 21 deltaPreambleMsg3 6 22 , 23 antennaInfoCommon 24 antennaPortsCount an2 25 , 26 p-Max 23, 27 ul-CyclicPrefixLength len1 28 29 , 30 radioResourceConfigDedicated 31 mac-MainConfig explicitValue : 32 drx-Config setup : 33 onDurationTimer psf10, 34 drx-InactivityTimer psf200, 35 drx-RetransmissionTimer psf2, 36 longDRX-CycleStartOffset sf320 : 2, 37 shortDRX 38 shortDRX-Cycle sf20, 39 drxShortCycleTimer 1 40 41 , 42 timeAlignmentTimerDedicated infinity 43 , 44 physicalConfigDedicated 45 pdsch-ConfigDedicated 46 p-a dB-3 47 , 48 cqi-ReportConfig 49 cqi-ReportModeAperiodic rm30, 50 nomPDSCH-RS-EPRE-Offset 0, 51 cqi-ReportPeriodic setup : 52 cqi-PUCCH-ResourceIndex 0, 53 cqi-pmi-ConfigIndex 79, 54 cqi-FormatIndicatorPeriodic widebandCQI : NULL, 55 ri-ConfigIndex 322, 56 simultaneousAckNackAndCQI FALSE 57 58 , 59 soundingRS-UL-ConfigDedicated setup : 60 srs-Bandwidth bw2, 61 srs-HoppingBandwidth hbw0, 62 freqDomainPosition 6, 63

93


duration TRUE, 1 srs-ConfigIndex 2, 2 transmissionComb 0, 3 cyclicShift cs0 4 , 5 antennaInfo explicitValue : 6 transmissionMode tm3, 7 codebookSubsetRestriction n2TxAntenna-tm3 : '11'B, 8 ue-TransmitAntennaSelection release : NULL 9 , 10 schedulingRequestConfig setup : 11 sr-PUCCH-ResourceIndex 0, 12 sr-ConfigIndex 12, 13 dsr-TransMax n64 14 15 16 , 17 securityConfigHO 18 handoverType intraLTE : 19 securityAlgorithmConfig 20 cipheringAlgorithm eea2, 21 integrityProtAlgorithm eia2 22 , 23 keyChangeIndicator FALSE, 24 nextHopChainingCount 3 25 26 27 28 29 30

31

94


5.1.5.2 RRC Connection Reconfiguration (from Specifications) Reference: (3GPP TS 36.331 Section 6.2.2) 1 -- ASN1START 2 3 RRCConnectionReconfiguration ::= SEQUENCE 4 rrc-TransactionIdentifier RRC-TransactionIdentifier, 5 criticalExtensions CHOICE 6 c1 CHOICE 7 rrcConnectionReconfiguration-r8 RRCConnectionReconfiguration-r8-IEs, 8 spare7 NULL, 9 spare6 NULL, spare5 NULL, spare4 NULL, 10 spare3 NULL, spare2 NULL, spare1 NULL 11 , 12 criticalExtensionsFuture SEQUENCE 13 14 15 16 RRCConnectionReconfiguration-r8-IEs ::= SEQUENCE 17 measConfig MeasConfig OPTIONAL,-- Need ON 18 mobilityControlInfo MobilityControlInfo OPTIONAL,-- Cond HO 19 dedicatedInfoNASList SEQUENCE (SIZE(1..maxDRB)) OF 20 DedicatedInfoNAS OPTIONAL,-- Cond nonHO 21 radioResourceConfigDedicated RadioResourceConfigDedicated OPTIONAL, -- Cond HO-22 toEUTRA 23 securityConfigHO SecurityConfigHO OPTIONAL,-- Cond HO 24 nonCriticalExtension SEQUENCE OPTIONAL -- Need OP 25 26 27 SecurityConfigHO ::= SEQUENCE 28 handoverType CHOICE 29 intraLTE SEQUENCE 30 securityAlgorithmConfig SecurityAlgorithmConfig OPTIONAL,-- Need OP 31 keyChangeIndicator BOOLEAN, 32 nextHopChainingCount NextHopChainingCount 33 , 34 interRAT SEQUENCE 35 securityAlgorithmConfig SecurityAlgorithmConfig, 36 nas-SecurityParamToEUTRA OCTET STRING (SIZE(6)) 37 38 , 39 ... 40 41 42 -- ASN1STOP 43

95


5.1.5.3 MobilityControInfo IE Reference: (3GPP TS 36.331 Section 6.3.4) -- ASN1START 1 2 MobilityControlInfo ::= SEQUENCE 3 targetPhysCellId PhysCellId, 4 carrierFreq CarrierFreqEUTRA OPTIONAL, -- Cond 5 HO-toEUTRA 6 carrierBandwidth CarrierBandwidthEUTRA OPTIONAL, -- Cond 7 HO-toEUTRA 8 additionalSpectrumEmission AdditionalSpectrumEmission OPTIONAL, -- Cond 9 HO-toEUTRA 10 t304 ENUMERATED 11 ms50, ms100, ms150, ms200, ms500, ms1000, 12 ms2000, spare1, 13 newUE-Identity C-RNTI, 14 radioResourceConfigCommon RadioResourceConfigCommon, 15 rach-ConfigDedicated RACH-ConfigDedicated OPTIONAL, -- Need 16 OP 17 ... 18 19 20 CarrierBandwidthEUTRA ::= SEQUENCE 21 dl-Bandwidth ENUMERATED 22 n6, n15, n25, n50, n75, n100, spare10, 23 spare9, spare8, spare7, spare6, spare5, 24 spare4, spare3, spare2, spare1, 25 ul-Bandwidth ENUMERATED 26 n6, n15, n25, n50, n75, n100, spare10, 27 spare9, spare8, spare7, spare6, spare5, 28 spare4, spare3, spare2, spare1 OPTIONAL -- Need 29 OP 30 31 32 CarrierFreqEUTRA ::= SEQUENCE 33 dl-CarrierFreq ARFCN-ValueEUTRA, 34 ul-CarrierFreq ARFCN-ValueEUTRA OPTIONAL -- Cond FDD 35 36

5.1.5.4 RACH-ConfigCommon IE Refer to Chapter 04. Accessibility KPI Analysis, section 4.1.5.

5.1.5.5 RACH-ConfigDedicated IE Reference: (3GPP TS 36.331 Section 6.3.2) -- ASN1START 37 38 RACH-ConfigDedicated ::= SEQUENCE 39 ra-PreambleIndex INTEGER (0..63), 40 ra-PRACH-MaskIndex INTEGER (0..15) 41 42

96


[7] Answer the following questions based on the RRC Connection Reconfiguration message provided in

Section 5.6.1 (or the local market example Exercise5.7.txt located on the class jump drive; ask the

instructor).

a) What is the purpose of this specific RRC Connection Reconfiguration message?

b) What is the PCI of the target cell?

c) What is the purpose of T304 and what is its value in this example?

d) What is the new C-RNTI given to the UE? What specific network entity assigned this new C-RNTI?

e) Referring to the RACH-ConfigCommon IE within the RRC Connection Reconfiguration message, how many

preambles are available to the UE to access the target cell?

f) Will the UE be using contention-based or non-contention-based random access to acquire the target cell?

97


5.1.6 Handover Completion

The following two illustrations detail the completion phase for both the X2- and S1-based intra-MME handover

scenarios.

Figure 13: X2 Handover Execution & Completion

5.1.6.1 eNodeB Event A3 Handover Counters In this section, eNodeB Event A3 handover-related counters will be discussed.



pmHoExeAttLteIntraF Pegged during the execution phase of an intra frequency handover when the source

eNodeB sends a RRC Connection Reconfiguration message to the UE which include


pmHoExeSuccLteIntraF Pegged during the execution phase of an intra frequency handover when the source

eNodeB receives either an X2 UE Context Release message, or a S1 UE Context Release

Command message, indicating the UE has successfully handover over to the target

eNodeB.

98



a) Open the counter file Exercise5.6.xlsx, which is provided on the Award Solutions jump drive. Consider rows

with pmHoExeAttLteIntraF_sum >= 500; this will remove statistically insignificant data. Sort on the HO Exec.

Fail % column and provide 3 cells with the highest % of handover execution failures:

• Cell1: _______________ HO Exec. Fail %: __________________________

• Cell2: _______________ HO Exec. Fail %: __________________________

• Cell3: _______________ HO Exec. Fail %: __________________________

b) Why is the failure rate high on these cells? Investigate by looking at the per-neighbor counts of Handover Exec.





c) What are the causes of the handover execution failures in the above cells?

• Cell1: __________________________________________________________________________

• Cell2: __________________________________________________________________________

• Cell3: __________________________________________________________________________

d) In general, what are the likely issues that cause an increase in the number of handover execution failures on a

cell?

__________

__________

__________

99


5.1.6.2 eNodeB Trace Example In this section, the intra-eNodeB handover call flow from the network’s perspective will be investigated.

[9] Open the Network log file X2 Handover.txt, which is provided on the Award Solutions jump drive, and

answer the following questions regarding an Outbound Intra-Frequency Handover.

a) Refer to the Measurement Report and provide the following:

Serving Cell: RSRP: dBm

Target Cell: PCI: RSRP: dBm ENBID:

b) What timestamp does the eNodeB send the Handover Request message?

c) Does the eNodeB receive a response from the Target eNodeB? If so, what message does it receive and

at what timestamp does is receive this message?

d) Is the preparation phase of the handover over successful? How can you tell?

e) Is the handover successful? How can you tell?

f) At what timestamp would the counter pmBestCellEvalReport be pegged?

g) At what timestamp would the counter pmHoPrepAttLteIntraF be pegged?

h) At what timestamp would the counter pmHoPrepSuccLteIntraF be pegged?

i) At what timestamp would the counter pmHoExeAttLteIntraF be pegged?

j) At what timestamp would the counter pmHoExeSuccLteIntraF be pegged?

100


5.2 Inter-Frequency Handover

As per the Inter-Frequency border guidelines FGA09, Ericsson’s L12A software introduced enhanced IFHO/IRAT

feature where a sector can be configured to support both IRAT and IFHO (Inter-Frequency Handover) -

whichever works best for the UE. There are two thresholds available with the feature ON - one threshold

(a2ThresholdRsrpPrim) is for IFHO use and another threshold (a2ThresholdRsrpSec) is for IRAT use. The

feature can only be activated/deactivated per eNodeB by Ericsson System Constant (SC 484)

‘enhancedBadCovDetectionActive’.

101


5.2.1 Event A2, A5 and A1 Parameters

This section provides details about the parameters related to LTE inter-frequency handover.

The following vendor parameters are configurable at the cell level. Vendor Parameter Name Managed Object Parameter Description

a2ThresholdRsrpPrim ReportConfigEUtraBadCov

Prim

The primary Reference Signal Received Power (RSRP)

threshold value for eventA2 (“Search” threshold).

a2ThresholdRsrpSec ReportConfigEUtraBadCov

Sec

The secondary Reference Signal Received Power (RSRP)

threshold value for eventA2 (“Critical” threshold).

hysteresisA2Prim ReportConfigEUtraBadCov

Prim

The hysteresis value for the primary eventA2 measurement.

timeToTriggerA2Prim ReportConfigEUtraBadCov

Prim

The time-to-trigger value for the primary eventA2

measurement.

triggerQuantityA2Prim ReportConfigEUtraBadCov

Prim

The quantity that triggers the eventA2 for the primary eventA2

measurement.

ueMeasurementsActive UeMeasControl Activates or deactivates A5/B2 measurements on EUTRAN

inter-frequencies, GERAN and UTRA frequencies for mobility

purposes.

a5B2MobilityTimer UeMeasControl The length of time the eNodeB waits for reports from A5/B2

measurements configured in the UE for mobility reasons. If

the value 0 is given, the timer will not be started.

a5Threshold1Rsrp ReportConfigA5 The Reference Signal Received Power (RSRP) threshold1

value for eventA5.

a5Threshold2Rsrp ReportConfigA5 The Reference Signal Received Power (RSRP) threshold2

value for eventA5.

hysteresisA5 ReportConfigA5 The hysteresis value for the eventA5 measurement.

timeToTriggerA5 ReportConfigA5 The time-to-trigger value for eventA5.

triggerQuantityA5 ReportConfigA5 The quantity that triggers the eventA5 for the eventA5

measurement.

[10] Using the local market CmDump located on the class jump drive or the Ericsson OSS, provide the

configured value for the following parameters.


a) a2ThresholdRsrpPrim

b) a2ThresholdRsrpSec

c) hysteresisA2Prim

d) timeToTriggerA2Prim

e) triggerQuantityA2Prim

f) ueMeasurementsActive

g) a5B2MobilityTimer

h) a5Threshold1Rsrp

i) a5Threshold2Rsrp

j) hysteresisA5

k) timeToTriggerA5

l) triggerQuantityA5

102


5.2.2 Inter-Frequency Handover Counter Analysis

In this section, eNodeB inter-frequency handover-related counters will be discussed.



pmHoPrepAttLteInterF The number of attempts to start outgoing intra-LTE inter-frequency handover preparation.

pmHoPrepSuccLteInterF The number of successful outgoing intra-LTE inter-frequency handover preparations.

pmHoExeAttLteInterF Pegged during the execution phase of an inter-frequency handover when the source

eNodeB sends a RRC Connection Reconfiguration message to the UE which include


pmHoExeSuccLteInterF Pegged during the execution phase of an inter-frequency handover when the source

eNodeB receives either an X2 UE Context Release message, or a S1 UE Context Release

Command message, indicating the UE has successfully handover over to the target

eNodeB.


a) Open the counter file Exercise5.6.xlsx, which is provided on the Award Solutions jump drive. Filter out the

statistically insignificant data, sort on the Inter-Frequency HO Exec. Fail % column and provide 3 cells with the

highest % of handover execution failures:

• Cell1: ______________ HO Exec. Fail %: __________________________

• Cell2: ______________ HO Exec. Fail %: __________________________

b) Why is the failure rate high on these cells? Investigate by looking at the per-neighbor counts of Handover Exec.




c) What are the causes of the handover execution failures in the above cells?

• Cell1: __________________________________________________________________________

• Cell2: __________________________________________________________________________

103


5.3 Optional Market-Specific Exercise

[12] Use this space to answer a market-specific question that may be provided by your instructor.

104

6 | Inter-RAT Mobility

6 Inter-RAT Mobility In this chapter, we investigate Inter-RAT Mobility between LTE and GPRS/UMTS. This includes both idle-mode

reselection as well as connected-mode handover.

6.1 Broadcasting Reselection Parameters

The first stage of reselection is the broadcasting of both the Cell and UMTS Reselection parameters to the UE.

This is achieved by means of System Information Blocks (SIB). SIB 3 transmits Cell Reselection parameters,

while SIB 6 transmits UMTS Reselection parameters.

Figure 1: Broadcasting Reselection Parameters

105


6.1.1 System Information Block 3 and System Information Block 1 (UE Log Message)

Reference: SCL08-CL38_East1/0808_01.log MS5 1 System Information Block 3 2 3 Time : 23:13:12.582 4 q-Hyst : dB4 5 s-NonIntraSearch : 3 6 threshServingLow : 3 7 cellReselectionPriority : 5 8 q-RxLevMin : -61 9 p-Max : 23 10 s-IntraSearch : 31 11 allowedMeasBandwidth : mbw25 12 presenceAntennaPort1 : True 13 neighCellConfig 14 Binary string (Bin) : 01 15 [0 ] : 0 16 [1 ] : 1 17 t-ReselectionEUTRA : 2 18 19 ///SIB 1 added for reference/// 20 21 MS5 22 System Information Block Type1 (DL-BCCH-SCH) 23 24 Time : 23:12:43.392 25 Vendor Header 26 Length : 43 27 Log Code (Hex) : 0xB0C0 28 HW Timestamp : (15162593.75 ms) 04:12:42.594 29 1.25 ms fraction : 0.00 30 CFN : 140 31 1.25 ms counter : 822816610075 32 RRC Signaling Header 33 Log Packet Version : 1 34 RRC Release Number : 8.7.0 35 Radio Bearer Id : 0 36 Physical Cell Id : 102 37 E-ARFCN : 5815 38 System Frame Number 39 System frame number : N/A 40 Sub frame number : N/A 41 Message Type : BcchSchDownlink 42 Message Length : 18 43 plmn-IdentityList 44 PLMN-IdentityList : 45 [0 ] : 46 plmn-Identity 47 mcc 48 MCC : 49 [0 ] : 3 50 [1 ] : 1 51 [2 ] : 0 52 mnc 53 MNC : 54 [0 ] : 4 55 [1 ] : 1 56 [2 ] : 0 57 cellReservedForOperatorUse : notReserved 58 trackingAreaCode : 16674 (0x4122) 59 cellIdentity : 54104847 (0x339930F) 60 cellBarred : notBarred 61

106


intraFreqReselection : allowed 1 csg-Indication : False 2 q-RxLevMin : -61 3 p-Max : 23 4 freqBandIndicator : 17 5 schedulingInfoList 6 SchedulingInfoList : 7 [0 ] : 8 si-Periodicity : rf8 9 sib-MappingInfo 10 SIB-MappingInfo : 11 [0 ] : 12 extensionBit0 : 0 13 item : sibType3 14 [1 ] : 15 si-Periodicity : rf64 16 sib-MappingInfo 17 SIB-MappingInfo : 18 [0 ] : 19 extensionBit0 : 0 20 item : sibType6 21 si-WindowLength : ms10 22 systemInfoValueTag : 3 23 24

107



Reference: (3GPP TS 36.331 Section 6.3.1) -- ASN1START 1 2 SystemInformationBlockType3 ::= SEQUENCE 3 cellReselectionInfoCommon SEQUENCE 4 q-Hyst ENUMERATED 5 dB0, dB1, dB2, dB3, dB4, dB5, dB6, dB8, dB10, 6 dB12, dB14, dB16, dB18, dB20, dB22, dB24, 7 speedStateReselectionPars SEQUENCE 8 mobilityStateParameters MobilityStateParameters, 9 q-HystSF SEQUENCE 10 sf-Medium ENUMERATED 11 dB-6, dB-4, dB-2, dB0, 12 sf-High ENUMERATED 13 dB-6, dB-4, dB-2, dB0 14 15 OPTIONAL -- Need 16 OP 17 , 18 cellReselectionServingFreqInfo SEQUENCE 19 s-NonIntraSearch ReselectionThreshold OPTIONAL, -- Need 20 OP 21 threshServingLow ReselectionThreshold, 22 cellReselectionPriority CellReselectionPriority 23 , 24 intraFreqCellReselectionInfo SEQUENCE 25 q-RxLevMin Q-RxLevMin, 26 p-Max P-Max OPTIONAL, -- Need 27 OP 28 s-IntraSearch ReselectionThreshold OPTIONAL, -- Need 29 OP 30 allowedMeasBandwidth AllowedMeasBandwidth OPTIONAL, -- Need 31 OP 32 presenceAntennaPort1 PresenceAntennaPort1, 33 neighCellConfig NeighCellConfig, 34 t-ReselectionEUTRA T-Reselection, 35 t-ReselectionEUTRA-SF SpeedStateScaleFactors OPTIONAL -- Need 36 OP 37 , 38 ... 39 40

6.1.3 Q-RxLevMin IE


The IE Q-RxLevMin is used to indicate for cell re-selection the required minimum received RSRP level in the (E-

UTRA) cell. Corresponds to parameter Qrxlevmin in 36.304 [4]. Actual value Qrxlevmin = IE value * 2 [dBm]. -- ASN1START 41 42 Q-RxLevMin ::= INTEGER (-70..-22) 43 44 -- ASN1STOP 45

6.1.4 ReselectionThreshold IE


The IE ReselectionThreshold is used to indicate a threshold for cell reselection. Actual value of threshold in dB

= IE value * 2. -- ASN1START 46 47 ReselectionThreshold ::= INTEGER (0..31) 48 49 -- ASN1STOP 50

108


6.1.5 CellReselectionPriority IE


The IE CellReselectionPriority concerns the absolute priority of the concerned carrier frequency/set of

frequencies (GERAN), as used by the cell reselection procedure. This corresponds with parameter "priority" in

TS 36.304 [4]. Value 0 means: lowest priority. The UE behavior for the case the field is absent, if applicable, is

specified in TS 36.304 [4]. -- ASN1START 1 2 CellReselectionPriority ::= INTEGER (0..7) 3 4 -- ASN1STOP 5

6.1.6 T-Reselection IE


The IE T-Reselection concerns the cell reselection timer TreselectionRAT for E-UTRA, UTRA, GERAN or

CDMA2000. The value is in seconds. -- ASN1START 6 7 T-Reselection ::= INTEGER (0..7) 8 9 -- ASN1STOP 10

6.1.6.1 EUtranCellFDD MO The following parameters are part of the EUtranCellFDD Managed Object and are configurable at the cell level.

3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

q-RxLevMin (SIB1) qRxLevMin (-140, -138, … -42, -44) dBm 2 dB Resolution

s-IntraSearch sIntraSearch

(systemInformationBlock3)

(0, 2, … 60, 62) dB 2 dB Resolution

q-Hyst qHyst


(0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14,

16, 18, 20, 22, 24) dB

n/a

s-NonIntraSearch sNonIntraSearch



threshServingLow threshServingLow



6.1.6.2 EUtranFreqRelation MO The following parameters are part of the EUtranFreqRelation Managed Object and are configurable at the cell

level. 3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

q-RxLevMin (SIB3) qRxLevMin (-140, -138, … -42, -44) dBm 2 dB Resolution

t-ReselectionEUTRA tReselectionEutra (0, 1, 2, 3. 4, 5, 6, 7) seconds n/a

cellReselectionPriority cellReselectionPriority (0, 1, 2, 3, 4, 5, 6, 7) n/a

109


[1] Using the CM Dump from the local market located on the class jump drive, provide the configured

value for the following parameters.


a) qRxLevMin (SIB 1)

b) sIntraSearch (systemInformationBlock3)

c) qHyst (systemInformationBlock3)

d) sNonIntraSearch (systemInformationBlock3)

e) threshServingLow (systemInformationBlock3)

f) qRxLevMin (SIB3)

g) tReselectionEutra

h) cellReselectionPriority

110


6.1.7 System Information Block 6 – UMTS Reselection Parameters

Reference: SIB-6.txt Message ID: 1611 1 Device ID: 1 2 Time: 01/21/13 17:58:44.648 3 Vendor Time: 4 Latitude: 37.6866875 Longitude: -122.1298294 5 Logical channel: BCCH_SCH 6 Message: System Information Block Type6 7 Message type: EUTRAN BCCH-DL-SCH 8 ACK SEQ: 9 MSG SEQ: 10 ACK REQ: 11 12 13 BCCH DL SCH Message 14 message -> 15 BCCH DL SCH MessageType index = 0 ( BCCH DL SCH MessageType index c1) 16 c1 -> 17 c1 index = 0 ( c1 index systemInformation) 18 systemInformation -> 19 systemInformation r8 -> 20 nonCriticalExtension included = 0 21 sib TypeAndInfo -> 22 sib TypeAndInfo size = 0 23 sib TypeAndInfo[0] -> 24 sib TypeAndInfo extension = 0 25 sib TypeAndInfo index = 4 ( sib TypeAndInfo index sib6) 26 sib6 -> 27 SystemInformationBlockType6 extension = 0 28 carrierFreqListUTRA FDD included = 1 29 carrierFreqListUTRA TDD included = 0 30 t ReselectionUTRA SF included = 0 31 carrierFreqListUTRA FDD -> 32 CarrierFreqListUTRA FDD size = 5 33 CarrierFreqListUTRA FDD[0] -> 34 CarrierFreqUTRA FDD extension = 0 35 cellReselectionPriority included = 1 36 carrierFreq = 9721 37 cellReselectionPriority = 2 38 threshX High = 7 39 threshX Low = 0 40 q RxLevMin = -60 dBm 41 p MaxUTRA = 74 42 q QualMin = 4 43 CarrierFreqListUTRA FDD[1] -> 44 CarrierFreqUTRA FDD extension = 0 45 cellReselectionPriority included = 1 46 carrierFreq = 4385 47 cellReselectionPriority = 3 48 threshX High = 7 49 threshX Low = 0 50 q RxLevMin = -60 dBm 51 p MaxUTRA = 74 52 q QualMin = 4 53 CarrierFreqListUTRA FDD[2] -> 54 CarrierFreqUTRA FDD extension = 0 55 cellReselectionPriority included = 1 56 carrierFreq = 4360 57 cellReselectionPriority = 3 58 threshX High = 7 59 threshX Low = 0 60 q RxLevMin = -60 dBm 61

111


p MaxUTRA = 74 1 q QualMin = 4 2 CarrierFreqListUTRA FDD[3] -> 3 CarrierFreqUTRA FDD extension = 0 4 cellReselectionPriority included = 1 5 carrierFreq = 9782 6 cellReselectionPriority = 6 7 threshX High = 7 8 threshX Low = 0 9 q RxLevMin = -60 dBm 10 p MaxUTRA = 74 11 q QualMin = 4 12 CarrierFreqListUTRA FDD[4] -> 13 CarrierFreqUTRA FDD extension = 0 14 cellReselectionPriority included = 1 15 carrierFreq = 512 16 cellReselectionPriority = 2 17 threshX High = 7 18 threshX Low = 0 19 q RxLevMin = -60 dBm 20 p MaxUTRA = 74 21 q QualMin = 4 22 CarrierFreqListUTRA FDD[5] -> 23 CarrierFreqUTRA FDD extension = 0 24 cellReselectionPriority included = 1 25 carrierFreq = 537 26 cellReselectionPriority = 2 27 threshX High = 7 28 threshX Low = 0 29 q RxLevMin = -60 dBm 30 p MaxUTRA = 74 31 q QualMin = 4 32 t ReselectionUTRA = 2 33

34

112



Reference: (3GPP TS 36.331 Section 6.3.1) -- ASN1START 1 2 SystemInformationBlockType6 ::= SEQUENCE 3 carrierFreqListUTRA-FDD CarrierFreqListUTRA-FDD OPTIONAL, -- Need 4 OR 5 carrierFreqListUTRA-TDD CarrierFreqListUTRA-TDD OPTIONAL, -- Need 6 OR 7 t-ReselectionUTRA T-Reselection, 8 t-ReselectionUTRA-SF SpeedStateScaleFactors OPTIONAL, -- Need 9 OP 10 ... 11 12 13 CarrierFreqListUTRA-FDD ::= SEQUENCE (SIZE (1..maxUTRA-FDD-Carrier)) OF CarrierFreqUTRA-FDD 14 15 CarrierFreqUTRA-FDD ::= SEQUENCE 16 carrierFreq ARFCN-ValueUTRA, 17 cellReselectionPriority CellReselectionPriority OPTIONAL, -- Need 18 OP 19 threshX-High ReselectionThreshold, 20 threshX-Low ReselectionThreshold, 21 q-RxLevMin INTEGER (-60..-13), 22 p-MaxUTRA INTEGER (-50..33), 23 q-QualMin INTEGER (-24..0), 24 ... 25 26 27 CarrierFreqListUTRA-TDD ::= SEQUENCE (SIZE (1..maxUTRA-TDD-Carrier)) OF CarrierFreqUTRA-TDD 28 29 CarrierFreqUTRA-TDD ::= SEQUENCE 30 carrierFreq ARFCN-ValueUTRA, 31 cellReselectionPriority CellReselectionPriority OPTIONAL, -- Need 32 OP 33 threshX-High ReselectionThreshold, 34 threshX-Low ReselectionThreshold, 35 q-RxLevMin INTEGER (-60..-13), 36 p-MaxUTRA INTEGER (-50..33), 37 ... 38 39 40 -- ASN1STOP 41

6.1.8.1 EUtranCellFDD MO The following parameters are part of the EUtranCellFDD Managed Object and are configurable at the cell level.

3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

t-ReselectionUTRA tReselectionUtra


(0, 1, 2, 3. 4, 5, 6, 7) seconds n/a

6.1.8.2 UtranFreqRelation MO The following parameters are part of the UtranFreqRelation Managed Object and are configurable at the cell

level. 3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter Resolution

cellReselectionPriority cellReselectionPriority (0, 1, 2, 3, 4, 5, 6, 7) n/a

threshX-High threshXHigh 0 – 62 Enumerated

(0, -0.5, -1.0, …, -31.0, -31) dB

1

(0.5 dB)

threshX-Low threshXLow 0 – 62 Enumerated

(0, -0.5, -1.0, …, -31.0, -31) dB

1

(0.5 dB)

113


[2] Using the CM Dump from the local market located on the class jump drive, provide the configured

value for the following parameters.


a) cellReselectionPriority

b) threshXHigh

c) threshXLow

d) tReselectionUtra

6.2 Initiating Reselection Measurements

The following figure illustrates the thresholds at which measurements of neighbor cells are triggered based on

RSRP measurements of the current cell. Note that there are two thresholds defined. The initial threshold

reached triggers intra-frequency neighbor measurements while the second threshold will initiate inter-

frequency or inter-RAT measurements.

Figure 2: Initiating Reselection Measurements

114


[3] Refering to Figure 2: Initiating Reselection Measurements, as well as the parameter values previously

determined, answer the following questions regarding the initiation of reselection measurements.

6.3 Triggering Reselection

In this section, the three scenarios that trigger the UE to reselect to a neighbor cell will be investigated. These

three scenarios include:

Reselection to an intra-frequency neighbor or equal-priority inter-frequency neighbor.

Reselection to a higher-priority UMTS neighbor (not included).

Reselection to a lower-priority UMTS neighbor.

6.3.1 Lower-Priority UMTS Reselection

The following illustrates the conditions required to trigger a reselection to a lower-priority UMTS neighbor.

Figure 4: Reselection to Lower-Priority UMTS Neighbor

a) Based on the parameter values in [1] and [2], at what RSRP threshold will the UE begin taking intra-

frequency neighbor measurements?

b) Based on the parameter values in [1] and [2], at what RSRP threshold will the UE begin taking UMTS

neighbor measurements?

c) Once the UE begins taking UMTS neighbor measurements, does it stop measuring intra-frequency

neighbor measurements?

115


[4] Referring to Figure 4: Reselection to Lower-Priority UMTS Neighbor, as well as the parameter values

previously determined, answer the following questions related to triggering a reselection to a lower-

priority UMTS neighbor.

6.3.2 Higher-Priority UMTS Reselection

The following illustrates the conditions required to trigger a reselection to a higher-priority UMTS neighbor.

Figure 5: Reselection to Higher-Priority UMTS Neighbor

a) Based on the parameter values in [1] and [2], what RSRP threshold must the serving cell reference signal

become to trigger a reselection to a lower priority cell?

a) What is the cellReselectionPriority of the UMTS neighbors in this log file?

b) What is the cellReselectionPriority of the LTE cells in this log file?

c) Based on these parameters, describe what must occur for an Inter-RAT reselection to a lower priority

UMTS cell to occur?

116


[5] Referring to Figure 4: Reselection to Lower-Priority UMTS Neighbor, as well as the parameter values

previously determined, answer the following questions related to triggering a reselection to a Higher-

priority UMTS neighbor.

6.4 Inter-RAT Handover Call Flow

6.4.1 Handover Call Flow

The figure below illustrates the basic call flow of an intra-frequency handover. The various stages will be

detailed in the following sections.

Figure 6: LTE IRAT Handover Call Flow

a) Based on the parameter values in [1] and [2], what RSRP threshold must the serving cell reference signal

become to trigger a reselection to a higher priority cell?

b) Based on these parameters, describe what must occur for an Inter-RAT reselection to a higher priority

UMTS cell to occur?

117


6.5 Inter-RAT Handover Algorithm and Parameters

Prior to examining the details of the various stages of intra-frequency handover, the vendor-specific

parameters related to Event A2 will be examined.

6.5.1 Event A2 Algorithm

This picture illustrates the key ideas behind the Event A2 Measurement and Reporting Algorithm as

implemented on the UE.

Figure 7: Event A2 Algorithm

118


6.5.2 Handover-Related Parameters

This section provides details about the parameters related to LTE Intra Frequency Handover. The parameters

are listed by the Managed Object in which they reside. The Managed Object defines how a parameter is

logically segregated within the vendor software and at what element it can be configured (i.e., eNodeB, Cell, or

Neighbor).

6.5.2.1 ReportConfigEUtraBadCovSec MO The following vendor parameters are part of the ReportConfigEUtraBadCovSec Managed Object and are

configurable at the cell level. 3GPP Parameter Name Vendor Parameter Name Vendor Configurable Range Parameter

Resolution

a2-Threshold (RSRP) a2ThresholdRsrpSec (-140, -139, ...-45, -44) dBm, 1 dB

a2-Threshold (RSRQ) a2ThresholdRsrqSec (-195, -194, ...-31, -30) dBm, .1 dB

Hysteresis hysteresisA2Sec (0, 5, … 145, 150) 0.1 dB Resolution

timeToTrigger ttimeToTriggerA2Sec (0, 40, 64, 80, 100, 128, 160, 256, 320,

480, 512, 640, 1024, 1280, 2560, 5120)

ms

n/a

triggerQuantity triggerQuantityA2Sec (RSRP, RSRQ) n/a

reportAmount reportAmountA2Sec (0, 1, 2, 4, 8, 16, 32, 64) 0 = Infinity n/a

reportInterval reportIntervalA2Sec (MS_120, MS_240, MS_480, MS_640,

MS_1024, MS_2048, MS_5120, MS_10240,

MIN_1, MIN_6, MIN_12, MIN_30, MIN_60)

n/a

6.6 Event A2 Measurement Configuration and UE Measurements

Figure 8: Event A2 Measurement Configuration

119


[6] Refering to Figure 7: Event A2 Algorithm, answer the following questions based on the RRC Connection

Reconfiguration message in section 5.2.2.1.

a) Based on the sMeasure value, at what RSRP threshold will the UE begin taking measurements?

b) This RRC Connection Reconfiguration message is configuring both Event A3 and Event A2. Based on the

reportConfigToAddModList and the measIdToAddModList list, provide the following:

1st Event A3: reportConfigId: measId:

1st Event A2: reportConfigId: measId:

2nd Event A2: reportConfigId: measId:

2nd Event A3: reportConfigId: measId:

c) Based on the log file parameters, at what value must the serving cells RSRP drop below to trigger an

Event A2 due to RSRP (assume the timeToTriggerA2Sec condition is met)?

d) Assume that an Event A2 has occurred and UE has transmitted a Measurement Report indicating such. If

the network does not respond and the RF conditions that triggered the Event A2 remain unchanged, how

often is the Measurement Report retransmitted?

e) What is the maximum number of times the Measurement Report can be retransmitted, assuming the

network does not respond and the RF conditions that triggered the Event A2 remain unchanged?

f) At what value must the serving cell’s RSRP be to leave Event A2 and cease sending Measurement

Reports?

120


6.7 Event A2 Measurement Reporting

This section will investigate the reporting of Event A2 via the RRC Measurement Report, as well as the

eNodeB’s initial evaluation of the reported cells.

Figure 9: Event A2 Measurement Reporting

6.7.1 Measurement Report: Reporting Event A2 (eNodeB Cell Trace)

Reference: SC-to-WCDMA.txt RRC_MEASUREMENT_REPORT 1 Time: 2012-12-06 22:19:49.823 2 3 EVENT_PARAM_SCANNER_ID: 000011100000000000000000 4 EVENT_PARAM_RBS_MODULE_ID: EVENT_VALUE_MASTER_DU [0] 5 EVENT_PARAM_GLOBAL_CELL_ID: 54068497 6 EVENT_PARAM_ENBS1APID: 3729 7 EVENT_PARAM_MMES1APID: 19627873 8 EVENT_PARAM_GUMMEI: 21165632331785 9 EVENT_PARAM_RAC_UE_REF: 149524513 10 EVENT_PARAM_TRACE_RECORDING_SESSION_REFERENCE: 5802 11 EVENT_PARAM_MESSAGE_DIRECTION: EVENT_VALUE_RECEIVED [0] 12 13 UL_DCCH_Message: 14 message: 15 c1: 16 measurementReport: 17 criticalExtensions: 18 c1: 19 measurementReport_r8: 20 measResults: 21 measId: 3 22 measResultServCell: 23 rsrpResult: 27 24 rsrqResult: 9 25

121


6.7.2 Measurement Report Message (from Specification)

See Section 5.4 for details regarding the Measurement Report message and its IEs.

[7] Answer the following questions based on the Measurement Report message provided in Section

6.7.1., or the local market example, Exercise6.10.txt, located on the class jump drive.

6.7.3 eNodeB Evaluation of Event A2 Measurement Report

Upon reception of the Event A2 Measurement Report, the Vendor eNodeB will evaluate its contents prior to

moving on to the RRC Connection Release phase. The license for Coverage Triggered WCDMA Session

Continuity must be enabled for this feature to work. The following parameters are part of the

WCDMASessionContinuity Managed Object and are configurable at the eNodeB level. Vendor Parameter Name Parameter Description

featureStateWcdmaSessionCo

ntinuity

Activates the UMTS Session Continuity feature for an eNodeB. Note that a valid

license for this feature must be installed to activate this feature.

licenseStateWcdmaSessionCo

ntinuity

Indicates if a valid license for this feature must be installed to activate this feature.

serviceStateWcdmaSessionCo

ntinuity

Indicates if the UMTS Session Continuity feature is operable for an eNodeB.

a) How can you tell this Measurement Report is related to an Event A2?

b) Based on this Measurement Report, provide the following information:

Serving Cell: PCI: n/a RSRP: dBm RSRQ: dB

122


6.8 Redirection to UMTS and UE Context Release

This section will investigate the redirection of the UE to UMTS via the RRC Connection Release message and

the subsequent UE Context Release.

Figure 10: Redirection to UMTS

6.8.1 RRC Connection Release – UMTS Redirection (eNodeB Cell Trace)

Reference: SC-to-WCDMA.txt RRC_RRC_CONNECTION_RELEASE 1 Time: 2012-12-06 22:19:49.823 2 3 EVENT_PARAM_SCANNER_ID: 000010100000000000000000 4 EVENT_PARAM_RBS_MODULE_ID: EVENT_VALUE_MASTER_DU [0] 5 EVENT_PARAM_GLOBAL_CELL_ID: 54068497 6 EVENT_PARAM_ENBS1APID: 3729 7 EVENT_PARAM_MMES1APID: 19627873 8 EVENT_PARAM_GUMMEI: 21165632331785 9 EVENT_PARAM_RAC_UE_REF: 149524513 10 EVENT_PARAM_TRACE_RECORDING_SESSION_REFERENCE: 5802 11 EVENT_PARAM_MESSAGE_DIRECTION: EVENT_VALUE_SENT [1] 12 13 DL_DCCH_Message: 14 message: 15 c1: 16 rrcConnectionRelease: 17 rrc_TransactionIdentifier: 0 18 criticalExtensions: 19 c1: 20 rrcConnectionRelease_r8: 21 releaseCause: other 22 redirectedCarrierInfo: 23 utra_FDD: 437 24

123


1 S1_UE_CONTEXT_RELEASE_REQUEST 2 Time: 2012-12-06 22:19:49.833 3 4 EVENT_PARAM_SCANNER_ID: 000010100000000000000000 5 EVENT_PARAM_RBS_MODULE_ID: EVENT_VALUE_MASTER_DU [0] 6 EVENT_PARAM_GLOBAL_CELL_ID: 54068497 7 EVENT_PARAM_ENBS1APID: 3729 8 EVENT_PARAM_MMES1APID: 19627873 9 EVENT_PARAM_GUMMEI: 21165632331785 10 EVENT_PARAM_RAC_UE_REF: 149524513 11 EVENT_PARAM_TRACE_RECORDING_SESSION_REFERENCE: 5802 12 EVENT_PARAM_MESSAGE_DIRECTION: EVENT_VALUE_SENT [1] 13 14 S1AP_PDU: 15 initiatingMessage: 16 procedureCode: 18 17 criticality: ignore 18 UEContextReleaseRequest: 19 protocolIEs: 20 elements: 21 UEContextReleaseRequest_protocolIEs_element 1: 22 id: 0 23 criticality: reject 24 MME_UE_S1AP_ID: 19627873 25 UEContextReleaseRequest_protocolIEs_element 2: 26 id: 8 27 criticality: reject 28 ENB_UE_S1AP_ID: 3729 29 UEContextReleaseRequest_protocolIEs_element 3: 30 id: 2 31 criticality: ignore 32 Cause: 33 radioNetwork: handover_desirable_for_radio_reason 34 35 S1_UE_CONTEXT_RELEASE_COMMAND 36 Time: 2012-12-06 22:19:49.867 37 38 EVENT_PARAM_SCANNER_ID: 000010100000000000000000 39 EVENT_PARAM_RBS_MODULE_ID: EVENT_VALUE_MASTER_DU [0] 40 EVENT_PARAM_GLOBAL_CELL_ID: 54068497 41 EVENT_PARAM_ENBS1APID: 3729 42 EVENT_PARAM_MMES1APID: 19627873 43 EVENT_PARAM_GUMMEI: 21165632331785 44 EVENT_PARAM_RAC_UE_REF: 149524513 45 EVENT_PARAM_TRACE_RECORDING_SESSION_REFERENCE: 5802 46 EVENT_PARAM_MESSAGE_DIRECTION: EVENT_VALUE_RECEIVED [0] 47 48 S1AP_PDU: 49 initiatingMessage: 50 procedureCode: 23 51 criticality: reject 52 UEContextReleaseCommand: 53 protocolIEs: 54 elements: 55 UEContextReleaseCommand_protocolIEs_element 1: 56 id: 99 57 criticality: reject 58 UE_S1AP_IDs: 59 uE_S1AP_ID_pair: 60 mME_UE_S1AP_ID: 19627873 61 eNB_UE_S1AP_ID: 3729 62 UEContextReleaseCommand_protocolIEs_element 2: 63

124


id: 2 1 criticality: ignore 2 Cause: 3 radioNetwork: release_due_to_eutran_generated_reason 4 5 6 7 S1_UE_CONTEXT_RELEASE_COMPLETE 8 Time: 2012-12-06 22:19:49.867 9 10 EVENT_PARAM_SCANNER_ID: 000010100000000000000000 11 EVENT_PARAM_RBS_MODULE_ID: EVENT_VALUE_MASTER_DU [0] 12 EVENT_PARAM_GLOBAL_CELL_ID: 54068497 13 EVENT_PARAM_ENBS1APID: 3729 14 EVENT_PARAM_MMES1APID: 19627873 15 EVENT_PARAM_GUMMEI: 21165632331785 16 EVENT_PARAM_RAC_UE_REF: 149524513 17 EVENT_PARAM_TRACE_RECORDING_SESSION_REFERENCE: 5802 18 EVENT_PARAM_MESSAGE_DIRECTION: EVENT_VALUE_SENT [1] 19 20 S1AP_PDU: 21 successfulOutcome: 22 procedureCode: 23 23 criticality: reject 24 UEContextReleaseComplete: 25 protocolIEs: 26 elements: 27 UEContextReleaseComplete_protocolIEs_element 1: 28 id: 0 29 criticality: ignore 30 MME_UE_S1AP_ID: 19627873 31 UEContextReleaseComplete_protocolIEs_element 2: 32 id: 8 33 criticality: ignore 34 ENB_UE_S1AP_ID: 3729 35 36

6.8.2 RRC Connection Release Message


The RRCConnectionRelease message is used to command the release of an RRC connection. -- ASN1START 37 38 RRCConnectionRelease ::= SEQUENCE 39 rrc-TransactionIdentifier RRC-TransactionIdentifier, 40 criticalExtensions CHOICE 41 c1 CHOICE 42 rrcConnectionRelease-r8 RRCConnectionRelease-r8-IEs, 43 spare3 NULL, spare2 NULL, spare1 NULL 44 , 45 criticalExtensionsFuture SEQUENCE 46 47 48 49 RRCConnectionRelease-r8-IEs ::= SEQUENCE 50 releaseCause ReleaseCause, 51 redirectedCarrierInfo RedirectedCarrierInfo OPTIONAL, -- Need 52 ON 53 idleModeMobilityControlInfo IdleModeMobilityControlInfo OPTIONAL, -- Need 54 OP 55 nonCriticalExtension SEQUENCE OPTIONAL -- Need 56 OP 57 58 59 ReleaseCause ::= ENUMERATED loadBalancingTAUrequired, 60

125


other,spare2, spare1 1 2 RedirectedCarrierInfo ::= CHOICE 3 eutra ARFCN-ValueEUTRA, 4 geran CarrierFreqsGERAN, 5 utra-FDD ARFCN-ValueUTRA, 6 utra-TDD ARFCN-ValueUTRA, 7 cdma2000-HRPD CarrierFreqCDMA2000, 8 cdma2000-1xRTT CarrierFreqCDMA2000, 9 ... 10 11 12 ///Deatails of this Spec Refererence omitted for clarity/// 13 14 -- ASN1STOP 15

[8] Referring to the specification references provided in this section, answer the following questions

based on the RRC Connection Release message provided in eNodeB Trace in Section 6.8.1, or the

local market example, Exercise6.11.txt, located on the class jump drive.

a) What is the purpose of this specific RRC Connection Release message?

b) What is type of network is the UE being directed to?

c) What is the frequency of this target network?

d) Has the target network reserved resources for this UE?

e) What is the “Cause” of the UE Context Release Request?

f) What is the “Cause” of the UE Context Release Command?

126


6.9 Session Continuity to UMTS

The final stage of the IRAT process is the UE tuning its receiver to the UMTS frequency and performing a

traditional Routing Area Update.

Figure 11: Session Continuity to UMTS

6.10 Counters

6.10.1 eNodeB Event A2 IRAT Counters

In this section, eNodeB Event A2 handover-related counters will be discussed.

6.10.1.1 EUtranCell MO The following Vendor counters are part of the EUtranCell Managed Object and are pegged at the cell level.

Vendor Counter Name Counter Type/MO Counter Description

pmBadCovEvalReport Peg/EUtranCell Pegged upon reception of an Event A2 Measurement

Report

pmUeCtxtRelSCWcdma Peg/EUtranCell Pegged upon reception of a S1 UE Context Release

Command as a result of an IRAT to UMTS

Based on analysis of Vendor eNodeB cell traces and counters, the counter pmBadCovEvalReport is

incremented for each Event A2 Measurement Report that is received. This includes Event A2 Measurement

Reports that do not invoke an INTERNAL_EVENT_BAD_COV_EVAL report.

The counter pmUeCtxtRelSCWcdma is pegged when the eNodeB receives a UE Context Release Command

from the MME, as a result of sending a UE Context Release Request with a cause of “inter-rat-redirection.”

127


6.11 CSFB Analysis

6.11.1 Circuit-Switched Fallback to UMTS

The final stage of the CSFB process is the UE tuning its receiver to the UMTS frequency and performing a

traditional Page Response.

Figure 12: CSFB to UMTS

128


6.12 Counters

6.12.1 eNodeB CSFB Counters

In this section, eNodeB CSFB handover-related counters will be discussed.

6.12.1.1 EUtranCell MO The following Vendor counters are part of the EUtranCell Managed Object and are pegged at the cell level.

Vendor Counter Name Counter Type/MO Counter Description

pmUeCtxtRelCsfbWcdma Peg/EUtranCell Pegged upon reception of a S1 UE Context Release

Command as a result of an CSFB to UMTS

6.13 CSFB Handover Log File Analysis

[9] For the following questions, refer to the Cell Trace file Exercise6.12.txt located on the class jump drive.

In this call, the UE has come out of Idle mode.

a) What is the purpose of the RRC Reconfiguration Message at time stamp 22:16:48.647?

b) Are there any Measurement Report messages in this log file? What is the trigger of the IRAT Handover?

_________________

c) Does the MME send a UE Context Release Command?

d) Based on this call flow, how many times would the following counters have pegged?

pmBadCovEvalReport:

pmUeCtxtRelCsfbWcdma:

e) Was this a successful IRAT Handover? How can you tell?

129


6.14 Optional Market-Specific Exercise

[10] Use this space to answer a market-specific question that may be provided by your instructor.

130

LTE Initial Attach (ONE APN, ONLY Default Bearer setup without PCRF/AAA/PCC interactions)

6. RRC: RRC Connection Request

0. Read Primary Sync Signal, Read Secondary Sync Signal 1. Read Reference Signal, Read PBCH [MIB] Read PCFICH, PDCCH, PDSCH [SIB1 and SIB2] 2. Calculate Path Loss 3. Open Loop PC

8. RRC: RRC Connection Setup

PDN UE MME HSS S-GW P-GW eNodeB

9. RRC: RRC Connection Setup Complete [EMM: Attach Request/ESM: PDN Connectivity Request]

10. S1-AP: Initial UE Message [EMM: Attach Request/ESM: PDN Connectivity Request]

13. S1-AP: Downlink NAS Transport [EMM: Authentication Request]

11. Diameter: Authentication Information Request

12. Diameter: Authentication Information Answer

27. GTPv2-C: Create Session Request

14. RRC: DL Information Transfer [EMM: Authentication Request]

15. RRC: UL Information Transfer [EMM: Authentication Response]

16. S1-AP: Uplink NAS Transport [EMM: Authentication Response]

17. S1-AP: Downlink NAS Transport [EMM: Security Mode Command]

18. RRC: DL Information Transfer [EMM: Security Mode Command]

19. RRC: UL Information Transfer [EMM: Security Mode Complete]

20. S1-AP: Uplink NAS Transport [EMM: Security Mode Complete]

21. S1-AP: Downlink NAS Transport [ESM: ESM Information Request]

22. RRC: DL Information Transfer [ESM: ESM Information Request]

23. RRC: UL Information Transfer [ESM: ESM Information Response]

24. S1-AP: Uplink NAS Transport [ESM: ESM Information Response]

25. Diameter: Update Location Request

26. Diameter: Update Location Answer

RRC Connection (SRB1)

28. GTPv2-C: Create Session Request

30. GTPv2-C: Create Session Response

29. GTPv2-C: Create Session Response

31. S1-AP: Initial Context Setup Request [E-RAB to Setup/EMM: Attach Accept/ESM: Activate Default EPS Bearer Context Request]

32. RRC: UE Capability Enquiry

33. RRC: UE Capability Information

34. RRC: Security Mode Command

35. RRC: Security Mode Complete

36. RRC: RRC Connection Reconfiguration [EMM: Attach Accept/ESM: Activate Default EPS Bearer Context Request]

37. RRC: RRC Connection Reconfiguration Complete

39. RRC: UL Information Transfer [EMM: Attach Complete/ESM: Activate Default EPS Bearer Context Accept]

RRC Connection (SRB1, SRB2)

S1-MME Bearer

Default Radio Bearer

S5/S8 GTP-C Default S5/S8 Bearer

S11 GTP-C

41. GTPv2-C: Modify Bearer Request

40. S1-AP: Uplink NAS Transport [EMM: Attach Complete/ESM: Activate Default EPS Bearer Context Accept]

42. GTPv2-C: Modify Bearer Response

Default S1 Bearer

5. MAC: Random Access Response

7.MAC: Contention Resolution/Uplink Assignment

4. PHY: Preamble/s

38. S1-AP: Initial Context Setup Response [E-RAB Setup List]

pmRrcConnEstabAtt

pmRrcConnEstabSucc

pmS1SigConnEstabAtt

pmS1SigConnEstabSucc

pmErabEstabAttInit

pmErabEstabSuccInit

AT&T Confidential Information

Target eNB

X2 Handover (Intra-MME)

RRC: Measurement Report (Reporting Event A3)

UE MME S-GW Source eNB

X2: Handover Request [RRC Context, UE Context, E-RAB List]

X2: Handover Request Acknowledge [T-eNB to S-eNB Transparent Container, Admitted E-RAB List]

pmBestCellEvalReport

pmHoPrepAttLteIntraF

RRC: RRC Connection Reconfiguration [MeasConfig for Event A3]

RRC: RRC Connection Reconfiguration Complete

pmHoPrepSuccLteIntraF

RRC: RRC Connection Reconfiguration [Mobility Control Info]


Random Access Procedure

pmHoExeAttLteIntraF

pmHoExeSuccLteIntraF

X2: SN Status Transfer [E-RAB UL & DL PDCP Sequence Number]

S1: Path Switch Request [E-RAB GTP-TEID]

S1: Path Switch Request Acknowledge

S11: Modify Bearer Request

S11: Modify Bearer Response

X2: UE Context Release

VS.HO.X2Att.E

VS.HO.X2Succ.E

RRC: Measurement Report (Reporting Event A3)

S1: Handover Required [S-eNB to T-eNB Transparent Container]

pmBestCellEvalReport

pmHoPrepAttLteIntraF

RRC: RRC Connection Reconfiguration [MeasConfig for Event A3]


pmHoPrepSuccLteIntraF

RRC: RRC Connection Reconfiguration [Mobility Control Info]


Random Access Procedure

pmHoExeAttLteIntraF

pmHoExeSuccLteIntraF

S1: eNB Status Transfer [E-RAB UL & DL PDCP Sequence Number]

S1: Handover Notify

S11: Modify Bearer Request

S11: Modify Bearer Response

S1: UE Context Release Command

VS.HHO.AttIntraMme

VS.HHO.SuccIntraMme

S1: Handover Request

S1: Handover Request Acknowledge S1: Handover Command

S1: MME Status Transfer

S1: UE Context Release Command

S1 Handover (Intra-MME)

UE Source eNB MME Target eNB S-GW

AT&T Confidential Information

atn438 lte ran troubleshooting (1of2) ericsson v1.9c ce att 926p

Documents

att att content

course book

att proprietary

att reserves

award solutions logos

inclusion of att content

moral rights

distribution rights