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DESCRIPTION
lteTRANSCRIPT
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eNodeB Operation & Maintenance Basics
Prepared by: Samsung
Approved by: RJIL
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Detailed Schedule
Day Course Topics
Day 1 LTE Basics
LTE Network Architecture
LTE Air Interface
eNodeB Call Processing
Day 2 Introduction to Samsung eNodeB
Samsung eNodeB Overview
LSM-R Overview
LSM-R Hands on
Day 3 eNodeB Growth
LSM-R Operations Basics
LSM-R Operations Hands on
eNodeB growth for PnP
Day 4 Troubleshooting
eNodeB Environment Checks
eNodeB Growth Troubleshooting
Post Test and Feedback
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Course Name: eNodeB O&M Basics
Course Objective
This module will enable participants to understand entry-level overview of Samsung eNodeB and operations
Who Should Attend
O&M Engineers, RAN engineers who do not have experience on Samsung platform
Pre-Requisite Basic understanding LTE
Morning Session (11am to 1:30pm)
Lun
ch b
reak
Afternoon Session (2:30pm to 6pm)
Day 1
Introduction to LTE
LTE Network Architecture
LTE Air Interface Basics
Samsung eNodeB Call Processing
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Good to Know
Keep your mobile phone in the silent mode during the session
Facebook/Twitter etc. Not Allowed. You can be online on your office mail
Need to sign attendance sheet at the start and end of each day
At the end of each training pre and post test will be conducted
Stick to break timings
Your valuable feedback will be taken at the end to enhance training experience
Certificate will be issued to successful participant
For logistics support contact the coordinator
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Agenda: Day 1
LTE Network Architecture
Cellular Architecture (2G and 3G)
LTE RAN & Core Philosophies
LTE Air Interface
Air Interface of EUTRAN
OFDMA in downlink and SC-FDMA in Uplink
FDD and TDD duplex methods
Scalable bandwidth 1.4MHz to 20MHz
MIMO (Multiple Input Multiple Output) Introduction
Samsung eNodeB Overview
Samsung eNodeB Specs
Samsung eNodeB Key Features
Samsung eNodeB Hardware
Commissioning of Samsung eNodeB
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LTE Network Architecture
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LTE Architecture Philosophy
Single node e-UTRAN Packet based while supporting real time conversational traffic Minimize number of interfaces Minimizes single points of failure Supports end-to-end QOS Supports QOS differentiation between control, user and O&M traffic Flat architecture Supports interworking with a variety of wireless networks
eUTRAN
EPC
IP Cloud
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LTE Network
IP Cloud
PCRF
HSS
OFCS
OCS
LSM-R
SON
MCE
GGSN
SGSN
MME SGW
PGW
MBMS GW
BMSC
X2
S1-MME S1-U
S11
S5
SGi
S6a
Gx
Gy
Gz
S3
S4
Gi
Gn
Gx
M1
M2
M3 Sm
SGmb
SGImb
LSM-C
WCDMA LTE NMS
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eNodeB
RRM functions
Radio Bearer Control
Radio Admission Control
Connection Mobility Control
Dynamic resource allocation UL & DL
IP header compression and encryption of user data
Selection of MME at the time of UE attachment
Measurements for mobility
Scheduling and transmission of paging and broadcast
eNodeB
eNodeB
X2
Uu
E-UTRAN
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MME S1-AP signalling
Signaling coordination for SAE Bearer Setup/Release
NAS signaling and security
Authentication, integrity Protection
Inter CN node signaling for mobility between 3GPP access networks (S3)
Location registration and Paging for Idle mode UE
Paging, TA list management, Tracking Area Updates
NE selection
PDN GW, Serving GW selection
MME selection for handovers with MME change
SGSN selection for handovers to 2G or 3G access network
Roaming for interworking HSS (S6a interface)
Interworking for Non-3GPP network
HRPD interworking (S101 interface) :
- Signaling for HRPD network and Optimized Handover
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Serving Gateway
Interfacing E-UTRAN for bearer
Local Mobility anchor point for inter- eNodeB Handover
Mobility anchoring for inter-3GPP mobility (terminating S4 and relaying the traffic between 2G/3G system and PDN GW) Packet routing & forwarding
Paging to ECM-Idle mode UE for incoming call
Accounting for inter-operator changing
UL/DL transport level packet marking e.g. setting the DiffServ Code Point, based on the QCI of the associated EPS bearer
Lawful Interception
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PDN Gateway Interfacing external PDN
Mobility anchor point between Non-3GPP and 3GPP
Packet routing & forwarding
UE IP address allocation
Per-user based packet filtering (i.e. deep packet inspection)
Packet screening (firewall functionality)
PCEF (Policy and Charging Enforcement Function) function
UL/DL bearer binding and UL bearer binding verification
Service level charging, gate control, rate enforcement
PCRF interworking and Policy / Charging control
DL rate enforcement based on APN-AMBR, MBR
UL/DL transport level packet marking e.g. setting the DiffServ Code Point, based on the QCI of the associated EPS bearer
Accounting for inter-operator charging
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HSS & PCRF
HSS (Home Subscriber Server)
User id, numbering, addressing information storage
User security information generation
mutual authentication and encryption for between UE and network
User location information storage
User profile information storage
PCRF (Policy and charging rule function)
Sending QoS and charging rule to P-GW(PCEF) for SDF (Service Data Flow) and IP-
CAN Session
P-GW (PCEF) performed QoS and Charging functions according to PCC rule
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eMBMS Elements
MCE (MBMS Coordination Entity)
The MBMS Coordination Entity (MCE) is a logical node that is responsible for allocating time and frequency resources. The MCE acts as an MBMS scheduler which allocates radio resources, performs session admission control and manages MBMS services.
MBMS GW
The MBMS GW is a logical entity whose main function is to deliver MBMS packets to each eNodeB transmitting the service. It uses IP multicast to deliver the downlink packets.
Broadcast Multicast Service Center (BM-SC)
The BM-SC is responsible for authentication, content authorization, billing and configuration of the data flow through the core network. It acts as a proxy content server.
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Samsung Smart Scheduler
Uses general purpose hardware platform IBM Blade Center HT Chassis and HS23 Blade server
Implemented in software by General Purpose Processor (GPP)
Minimizes inter-cell interference
Improves cell-edge throughput
Centralized management for multiple eNBs
10 blades per server support total 2880 cells
X2
SC1
SC1
LSM
E-UTRAN
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Interfaces X2 Interface
Between eNodeB.
It supports the exchange of signaling info between eNBs most commonly for Handover
Also supports forwarding of user PDUs
S1-MME Interface
S1-MME for exchange of signaling messages between the eNB and the MME
S1-U Interface
S1-U for the transport of user datagram's between the eNB and the Serving Gateway (S-GW)
Supports Inter eNodeB path switching during handover
S3 Interface
Interface between SGSN and MME
Enables user and bearer information exchange for inter 3GPP access
Manages Network mobility in idle and/or active
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Interfaces S4 Interface
Interface between SGSN and Serving SAE Gateway
It provides control and mobility support between GPRS Core & 3GPP
Anchor function of Serving GW
Alternate plane tunnel in case of no Direct Tunnel
S5 Interface
Interface between S-GW and P-GW
User plane tunneling and tunnel management
It is used for Serving GW relocation due to UE mobility or connections to a non-collocated PDN GW
S6a Interface
Interface between HSS and MME
Enables transfer of subscription and authentication data
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Interface S8 Interface Interface between Serving GW in the VPLMN and the PDN GW in the HPLMN.
Inter-PLMN reference point providing user and control plane between the Serving GW in the VPLMN and the PDN GW in the HPLMN
S10 Interface Reference point between MMEs for MME relocation and MME to MME information transfer
S11 Interface Reference point between MME and Serving GW
Gx Interface It provides transfer of (QoS) policy and charging rules from PCRF to Policy and Charging
Enforcement Function (PCEF) in the PDN GW
SGi Interface It is the reference point between the PDN GW and the packet data network. Packet data
network may be an operator external public or private packet data network or an intra operator packet data network, e.g. for provision of IMS services. This reference point corresponds to Gi for 3GPP accesses.
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LTE Protocol Stack User Plane
User Plane - consists of PDCP, RLC, MAC, and PHY layers, responsible for transmitting user data (e.g. IP packets) received from the higher layer. All protocols in the user plane are terminated in the eNB.
Interface between UE and eNB
Application
IP
PDCP
RLC
MAC
L1
IP
GTP-U
UDP-IP
L2
L1
UE
LTE-Uu S1-U S5/S8
eNB
PDCP
GTP-U
RLC UDP-IP
L2 L2
L1 L1
GTP-U
GTP-U
UDP-IP UDP-IP
L2 L2
L1 L1
Relay Relay
S-GW
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LTE Protocol Stack Control Plane
Control Plane - consists of NAS, RRC, PDCP, RLC, MAC, and PHY layers. Located above the wireless protocol, the NAS layer is responsible for UE authentication between the UE and MME, security control, and paging/mobility management of UEs in LTE idle mode, all protocols except the NAS signal are terminated in the eNB.
NAS
RRC
PDCP
RLC
MAC
L1
NAS
S1 - AP
SCTP
IP
L2
L1
UE
LTE-Uu S1-MME
RRC
S1 - AP
PDCP SCTP
RLC IP
MAC L2
L1 L1
Relay
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Protocol Stack
Interface between eNB and EPC : A physical connection between the eNB and EPC is established through the FE and GE, and the interface standards should satisfy the interface between the LTE S1-U and S1-MME. The user plane uses the GTP-User (GTP-U) above the IP, and the control plane uses the SCTP above the IP.
GTP-U
UDP
IP
MAC
PHY
GTP-U
UDP
IP
MAC
PHY
User Plane PDUs
User Plane PDUs
SCTP
IP
MAC
PHY
SCTP
IP
MAC
PHY
S1-AP S1-AP
eNB S-GW S1-U
eNB MME S1-MME
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Interface between eNodeB
Interface between eNodeB
A physical connection between the eNBs is established through the FE and GE, and the interface standards should satisfy the LTE X2 interface. The user plane protocol stacks between the eNBs are shown below
GTP-U
UDP
IP
L2
L1
GTP-U
UDP
IP
L2
L1
User Plane PDU
User Plane PDU
SCTP
IP
L2
L1
SCTP
IP
L2
L1
X2-AP X2-AP
eNB X2-U X2-C
eNB eNB eNB
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Interface between eNB and LSM
A physical connection between the eNB and LSM is established through the FE and GE, and the interface standards should satisfy the FTP/SNMP interface. The interface protocol stacks between the eNB and LSM are shown below
TCP UDP
IP
L2
FTP SNMP
L!
TCP UDP
IP
L2
FTP SNMP
L1
eNB LSM FTP/SNMP
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Transport Network Hierarchy
CSR
CSR
CSR CSR
AG1
AG1 AG1
AG1
AG2AG2
AG3 AG3
eNBeNB
eNB
eNB
A pair of AG3 routers per site
Up to 16 pairs of AG2 routers
Dual-homing with AG3 routers
Up to 10 AG1 rings
Up to 4 AG1 routers in a ring
Dual-homed ring with AG2 routers
Up to 4 CSR rings
Up to 5 (fiber) or 4 (MW or fiber + MV)
eNBs per ring
Dual-homed with AG1 routersCSR and eNB
AG2 node
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R4G Network Deployment Quantification
Mumbai
Zones ( 2)
NP GW
OCS
NP GW MNP GW IMS Apps
eSMLC / GMLC
LIM - BE
IPSM / SMSC NW IVR
Content Mgmt Self Care OCS OSS
MNP GW
OCS
IMS Apps IPSM / SMSC NW IVR
eSMLC / GMLC
Content Mgmt
Regions (4)
EPC ( 18)
Delhi
IMS Core
MGCF
TAS/OTM
DNS/ENUM
NPDB
PCRF
DRA
HSS
AAA / PS
Ld Bal.
West (Mumbai)
NIMS
eMBMS GW
BMSC MCE DPI L4/L7
NIMS
MRF SBC WAG LIM FE IBR L2 SW
MME SAE GW
LSM R/C
Circles ( 22)
MGW RAN Scheduler eNodeB
South (Chennai)
IMS Core
MGCF
TAS/OTM
DNS/ENUM
NPDB
PCRF
DRA
HSS
AAA / PS
Ld Bal.
North (Delhi)
IMS Core
MGCF
TAS/OTM
DNS/ENUM
NPDB
PCRF
DRA
HSS
AAA / PS
Ld Bal.
East (Kolkata)
IMS Core
MGCF
TAS/OTM
DNS/ENUM
NPDB
PCRF
DRA
HSS
AAA / PS
Ld Bal.
Zonal & Regional Level Nodes will work in Active- Active (Load sharing) mode
EPC++ EPC IMS Wi-Fi Supporting OSS/BSS Legend RAN
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Summary
LTE architecture is completely packet-based
Single node RAN
Flat architecture EPC
eNodeB performs all the RRM functions
MME performs all control plane core functions
S-GW is the local mobility anchor. Facilitates inter-3GPP handovers
P-GW assigns IP address and applies policy and QoS
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Quiz
Radio resources are allocated by
eNodeB
S-GW
_____ establishes a connection between the UE and EPC
S-GW
P-GW
MME
During handover DL data is buffered at
S-GW
MME
P-GW
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LTE RAN Technologies
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LTE Key Parameters
Frequency Range UMTS FDD bands and UMTS TDD bands
Channel Bandwidth, 1Resource Block (RB) = 180KHz
1.4MHz 3MHz 5MHz 10MHz 15MHz 20MHz
6 RBs 15RBs 25RBs 50RBs 75RBs 100RBs
Modulation scheme
Downlink: QPSK, 16QAM, 64QAM Uplink: QPSK, 16QAM, 64QAM (optional for handset)
Multiple Access Downlink: OFDMA Uplink: SC-FDMA
MIMO Transmit diversity, Cyclic delay diversity (Max. 4 antenna at Base station & handset) Spatial multiplexing, Multiuser MIMO
Peak Data rate Downlink: 150Mbps (UE category 4, 2x2 MIMO, 20MHz) 300Mbps (UE category 5, 4x4 MIMO, 20MHz) Uplink: 75Mbps (20MHz)
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Cyclic Prefix Cyclic Prefix (CP) is transmitted in the guard time interval
OFDMA symbol duration including CP is approximate 71.4 s.
Long duration when compared with 3.69s for GSM and 0.26s for WCDMA
Symbol length without CP: 66.67s (1/15kHz)
1 2
3 4
time
TSYMBOL
Time Domain
time
time
Tg
1
2
3
time
4
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Cyclic Prefix Details Copies the last part of a symbol shape for a duration of guard-time and attach it in front of the symbol
CP Types
Normal CP: for small cells or with short multipath delay spread
Extended CP: designed for use with large cells or those with long delay profiles
t
Total symbol time T(s)
Guard Time T(g)
CP T(g)
Useful symbol time T(b)
Note: CP represents an overhead resulting in symbol rate reduction.
Last part of the symbol is used as Cyclic Prefix
(CP)
CP ratio = T(g)/T(b)
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OFDMA
Flexible resource allocation
Robustness against multipath
The peak (centre frequency) of one subcarrier
intercepts the nulls of the neighbouring subcarriers
15 kHz in LTE: fixed
Total Bandwidth
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OFDM Transmission Basics
Data is sent in parallel across the set of subcarriers
The throughput is the sum of the data rates of subcarriers
Power
Frequency
Bandwidth
01 10 11 01 01
10
11
01
OFDMA Symbol
S/P
Serial to Parallel
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LTE Time-Frequency Grid
Fast time-domain scheduling
Radio resources on a time-frequency grid
Freq
ue
ncy
Resource Block 180 KHz x 0.5 ms Each RB = 12 x 7 = 84 REs
Time
Sub-carrier 1
Sub-carrier 12
Symbol 0 Symbol 6
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FFT in OFDM Fast Fourier Transform (FFT) and the Inverse Fast Fourier Transform (IFFT) allows to move between time and frequency domain representation
OFDM signals are generated using the IFFT
Fourier Transform
Inverse Fourier Transform
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OFDMA Operation Multiple access is achieved in OFDMA by assigning subsets of subcarriers to individual users as shown below
S/P IFFT CP
Modulation mapping e.g.
QPSK symbols
Transmitter Receiver
P/S FFT CP
Remove
Modulation mapping e.g.
QPSK symbols
Total Channel Bandwidth
Transmitted Sub-Carriers
User 1
User 2
User 3
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OFDMA PAPR Ratio The transmitted power is the sum of the powers of all the subcarriers.
The higher the peaks, the greater the range of power levels.
Not best suited for use with mobile (battery-powered) devices
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SC-FDMA & OFDMA Time-Frequency View
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LTE FDD and TDD Modes
Uplink Downlink
Bandwidth
up to 20MHz
Duplex Frequency
f
t Bandwidth
up to 20MHz
Gu
ard
Pe
rio
d
f
t
Uplink
Downlink
Bandwidth
up to 20MHz
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LTE Radio Frames, Slots and Sub frames FDD mode
The basic EUTRAN Radio Frame is 10 ms long.
The EUTRAN Radio Frame is divided into 20 slots, each one 0.5 ms long.
Always two slots together form a subframe. The subframe (1 ms) is the smallest time unit the scheduler assigns to physical channels.
In case of TDD there is a time offset between uplink and downlink transmission.
Frame structure type 1
#0 #1 #2 #3 #18 #19
1 radio frame (Tf = 307200Ts = 10 ms)
1 slot (Tslot = 15360Ts = 0.5 ms)
1 subframe (1 ms)
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LTE Frame Details
Frame (10ms)
10 Sub-frames (1ms) per frame
2 slots (0.5ms) per sub-frame
7 OFDM symbols per slot
Frame (10msec)
Sub frame 0
0.5 msec 0.5 msec
Slot 0 Slot 19 Slot 1 Slot 18
Sub frame 9
. .
OFDM SYMBOL 0 OFDM SYMBOL 13
CP0=5.2uSec - CP1 TO CP13 =4.7uSec Single Sub Frame (1 ms)
.. ..
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LTE Radio Frames, Slots and Sub frames TDD mode
Frame structure type 2
0 1 2 3 4 5 6 7 8 9
TDD Frame 10ms , 10 subframes 1ms each
Special Subframes 1 & 6
0 2 3 4 5 7 8 9
DwPTS
Gp
UpPTS DwPTS
Gp
UpPTS
LTE Frame Structure Type 2: Applicable to TDD
Every subframe will have two slots of 0.5ms as in FDD Frame
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LTE Radio Frames, Slots and Sub frames TDD mode
LTE TDD Special Subframe Configuration (UL & DL capacity)
Asymmetric UL/DL Capacity Allocation
Single sub-frame for UL and 8times sub-frame for DL per 10ms frame
UE is informed about UL/DL configuration via SIB-1, which is broadcast via Broadcast Channel (BCH)
UL/DL Configuration
Downlink-To-Uplink Switch-Point Periodicity
Subframe Number 0 1 2 3 4 5 6 7 8 9
0 5 ms D S U U U D S U U U
1 5 ms D S U U D D S U U D
2 5 ms D S U D D D S U D D 3 10 ms D S U U U D D D D D
4 10 ms D S U U D D D D D D 5 10 ms D S U D D D D D D D
6 5 ms D S U U U D S U U D
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Summary
OFDMA allows flexible resource allocation
OFDMA maps one modulation symbol on a subcarrier and transmits multiple subcarriers in parallel
A Cyclic Prefix is added to an OFDMA symbol for protection against ISI
OFDMA is implemented using FFT
Due to high PAPR issues, LTE uplink uses SC-FDMA
SC-FDMA transmits in series, mapping each modulation symbol on all the allocated subcarriers
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Quiz
Give two advantages of OFDMA
Flexible bandwidth allocation
Robustness against multipath
SC-FDMA sends ____ modulation (e.g. QPSK) symbol(s) on ____ subcarrier(s)
1, N
N, N
1/N, N
FFT is a must in implementing OFDMA
True
False