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DOCUMENT

Enterprise SON use cases

November 2013

066.05.01

scf.io/

SMALL CELL FORUM

RELEASE Five

R UR A L & R E M OT E


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Small Cell Forum works to accelerate small cell adoption to changethe shape of mobile networks and maximize the potential of mobileservices.

We are not a standards organization but partner with organizations that informand determine standards development. We are a carrier-led organization. Thismeans our operator members establish requirements that drive the activitiesand outputs of our technical groups.

Our track record speaks for itself: we have driven the standardization of keyelements of small cell technology including Iuh,FAPI/SCAPI, SON, the small cellservices API,TR-069 evolution and the enhancement of the X2 interface.

At the time of writing, Small Cell Forum has more than 140 members, including68 operators representing more than 3 billion mobile subscribers – 46 percent of the global total – as well as telecoms hardware and software vendors,content providers and innovative start-ups.

This document forms part of Small Cell Forum’s Release Five: Rural &Remote that considers the opportunities and perceived barriers associatedwith the deployment of small cells in rural and remote scenarios, includingdisaster recovery, military installations, as well as verticals such as oil and gas,maritime, aviation and automotive.

The Small Cell Forum Release Program has now established business cases

and market drivers for all the main use cases, clarifying market needs andaddressing barriers to deployment for residential, enterprise and urban smallcells.

Small Cell Forum Release website can be found here: www.scf.io

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Report title: Enterprise SON use cases Issue date: 08 November 2013

Version: 066.05.01

Scope

The Enterprise self-organizing networks (SON) use cases document is an informative

document. Its scope is to capture the use cases that illustrate, in a comprehensivemanner and building upon the Enterprise femto deployment guidelines document [1],how the self-organizing function helps in the configuration, optimization andmaintenance of enterprise small cell networks with very low or no manualintervention.

Specifically, the informative use cases are targeted towards the two predominant radioaccess technologies (RAT) – UMTS terrestrial access network (UTRAN) and evolvedUTRAN (E-UTRAN). In context, the 3GPP specified functions such as self-configuration,automatic neighbor relations (ANR), physical cell identity/primary scrambling codeassignments, resource management and load balancing, robust handoff and randomaccess channel (RACH) optimization are addressed.

The target audience is systems and network deployment engineers as well asdesigners working on SON solution architectures and SON algorithms.


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Executive summary

The context and the definitions of small cells and enterprise small cell networks are done well in

[1]. For convenience, the relevant text is repeated here.

Small cells are low-power cellular base stations typically deployed in residential, enterprise orhotspot settings. Small cells provide excellent user experience through better coverage for voiceand very high data throughputs. Small cells can also offload traffic from macrocell network andenable new applications such as location-based services.

Enterprise small cell deployments refer to commercial multi-cell deployments that cover a widerange of settings such as enterprise buildings, small offices and shopping malls. Enterprise small

cell deployments differ from residential ones due to large number of users, RF interactionsbetween small cells, mobility and handover from one small cell to another, potentially large RFvariations inside the buildings and potentially large coverage area per small cell.

The background document [1] provides recommendations for deployment, configuration and

operation of enterprise small cells. This document covers specifically the SON function as itpertains to the enterprise small cell networks. The document aims to highlight, to theappropriate detail possible, without infringing or architecture or algorithm choices, use cases forthe SON function. The broad goal of SON is to enable the configuration, deployment,

optimization, operation and maintenance of dense networks across multiple scales with very lowor no manual input or feedback and this spirit is maintained in the document.

For a very small number of use cases in an enterprise context, there is scope for a limitedinvolvement or assistance of IT technicians. Hence, a separate section (Section 4) is added toshow these use cases. The intent is for the document to stand on its own and address thepredominant usage of SON through the use cases of Section 3 with Chapter 4 occupying a verynarrow slice of usage. Chapters 1, 2 and 3 have validity beyond the enterprise while Chapter 4is also limited only to the enterprise context.

Specifically, the following topics are addressed:

1.

Enterprise SON use cases addressing the two predominant radio accesstechnologies – UTRAN and EUTRAN.

2. SON use cases addressing the full life cycle of the network – from initialdeployment and configuration through self-optimization as well asmaintenance aspects.

3.

SON functionality specifically addressing the 3GPP identified areas such as

self-configuration, neighbor discovery, parameters (PCI/PSC) optimization,resource sharing (for interference management and capacity optimization asfinal goals), load balancing, robust handoff and RACH parameteroptimization.

4.

In addition some attempt is made to address maintenance aspects of SON.

The goal of this informative document is to be useful to system architects and algorithmdesigners working on architectures and SON functions at the front-end of the design process aswell as network designers at the back-end. Naturally, the goal is to illustrate that if the front-end designers cover the use cases in the design stage, then in the back-end the networkengineer will benefit significantly.

The real benefit is, of course, to both the network operators and users in terms of reducedcapex and opex for the same or better level of service.


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Contents

1. Introduction .....................................................................1

2. SON and SON function ......................................................3

2.1 SON function ...................................................................... 3

2.2 SON features ...................................................................... 3

2.3 SON management ............................................................... 5

3. Enterprise SON use cases .................................................7

3.1 Glossary of terms ................................................................ 7

3.2 Configuration ...................................................................... 8

3.3 Planning, deployment and operation ...................................... 9

3.4 Optimization ..................................................................... 13 3.5 Maintenance ..................................................................... 18

4. IT technician assisted SON ............................................. 19

4.1 General use cases ............................................................. 19

4.2 Specific examples .............................................................. 23

5. Summary ........................................................................ 26

References ................................................................................ 27

Tables

Table 3-1 Glossary of terms ........................................................................... 7 Table 3-2 Small cell initial configuration ........................................................... 8

Table 3-3 PCI assignment and conflict resolution............................................... 9

Table 3-4 Adding a new small cell to an enterprise network ................................ 9

Table 3-5 Adding many new small cells to an enterprise network ....................... 10

Table 3-6 Decommissioning a small cell from an enterprise network ................... 11

Table 3-7 Suspending a small cell from operation ............................................. 11

Table 3-8 Returning a suspended small cell to normal service ............................ 12

Table 3-9 Discovering a new neighbor in an LTE network .................................. 12

Table 3-10 Deleting a neighbor in LTE and UMTS ............................................... 13

Table 3-11 Optimization of small cell transmit power by SON function .................. 13 Table 3-12 Load and interference management with macro network .................... 14

Table 3-13 Load balancing .............................................................................. 15

Table 3-14 Mobility robustness optimization ...................................................... 16

Table 3-15 RACH optimization ......................................................................... 16

Table 3-16 SON mobility robustness optimization between LTE and UMTS ............. 17

Table 3-17 SON load balancing between LTE and UMTS ...................................... 17

Table 3-18 Dissemination of SON metrics ......................................................... 18

Table 4-1 Provisioning and use of IT technician interface ................................... 19

Table 4-2 IT technician assisted optimization of small cell position ..................... 20

Table 4-3 SON function initiated IT technician walk test .................................... 22


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Table 4-4 IT technician assisted optimization of small cell position – evenspread example ............................................................................. 23

Table 4-5 SON function initiated walk test example: TX power calibration ........... 25

FiguresFigure 1-1 Deployment layers and context of SON functions ................................ 2

Figure 2-1 Overview of SON features ................................................................ 5

Figure 2-2 SON management ........................................................................... 6

Figure 4-1 Example IT technician user interface ................................................ 20


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1. Introduction

The concepts of small cell network and enterprise small cell networks are covered in[1].

The need for and the functionality of SON functions are extensively covered inliterature (see for example [2] and references therein). Specifically, SON functionscope and coverage within the 3GPP context are addressed in [3] (and referencestherein).

The SON function is not a specific node or element in the network. Rather, as the

name implies, it is a collection of functional entities that address the specific needsdiscussed in the references pointed to above. In an architecture and algorithminstantiation sense the functions lend themselves to a large number of choices.

Further, because heterogeneous networks are a significant context of deployment, theSON functions vary according to the scale in which they are deployed (macro versus

small cells, etc.) and multiple SON functions may co-exist in a given operatorsnetwork together fulfilling the overall business needs of the operator. As such theseSON functions need to behave co-operatively and in the interest of the overall costfunctions and policies.

Enterprise small cell networks are, as the name implies, networks of small cellsdeployed to enhance the experience of the users inside the enterprise. The networkscould be for closed subscriber groups (CSG), prioritized for enterprise users or open.Each might entail different optimization criteria and the SON function must operateunder the constraints.

Without intending in any way to be comprehensive (or even specific in all contexts)

the following figure shows how the various scales might be deployed and mightinteract with each other.


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Figure 1-1 Deployment layers and context of SON functions

It might also be noted that the SON functions can reside in the same plane wherecontrol and user data flow (between macro/ small cells and gateway/EPC, forexample) or in the direction of the management plane (EMS/ACS, NMS/OSS) or bothdepending on the specific function being accomplished.

In addition, since the networks can be multi-RAT, it is possible for a single SONfunction to optimize across the two or more RAT or for each RAT to have its own SONfunction working co-operatively with the SON functions of other RAT.

Certain aspects of SON functions might have seeming overlap with normal radioresource manager (RRM) functions. However, as explained later, SON functionalityand RRM functionality each have their specific domain. This allows the RRM to perform

its normal functions (primarily radio bearer control, radio admission control,connection mobility control [4]) while the SON function can optimize RRMparameters/operation as part of multi-cell co-ordination. It is important to note thisdistinction while understanding the scope of the SON function. Where necessary, thisdistinction is again pointed out as appropriate.

The scope of this document is narrowly to focus upon the SON function addressing theenterprise deployments and even more specifically illustrate the SON function throughproperly designed use cases, whether they be single RAT (intra and inter-frequency)or multi-RAT (3G and LTE).


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2. SON and SON function

‘Self-organising networks (SON)’ describes a set of features and capabilities designed

to reduce or remove the need for manual activities in the lifecycle of network

equipment and the services it provides. The SON concepts and terminology describedin [3] are used here to describe use cases for SON in a small cell enterprisedeployment.

Note, although the concepts described in [3] are focused on LTE SON use cases, this

document applies those concepts generically to both LTE small cells and 3G small celldeployments.

2.1 SON function

This note describes use cases of activities involving SON features, and uses the term ‘SON function’ to describe the logical entity which provides the algorithms, datastorage and interactions with other nodes to perform the SON activities. This term isdeliberately non-specific about where this SON function is located, and as such

encompasses the options for this entity to be using any of the centralized SON model,the distributed SON model, or the hybrid SON model, as described in [3]. In some ofthe use cases, it is clear there must be some distributed element to the SON Function

(e.g. when SON-related information is to be exchanged over X2 with other small cells)for the use case to be as described, and in other use cases it is clear that there mustbe some centralised SON function (e.g. for holding centralized data and applyingcentral control of multiple small cells) is inferred.

The use of the term ‘SON function’ is also not specific about how much influence thesmall cell SON features may have on the operation of the macrocells. The macrocellsmay be totally autonomous, taking no account of the small cell network in their

management of load and interference (maybe including separate autonomousmacrocell SON functions), or they may have SON features tightly integrated with theSON function of the small cells, balancing the load and interference between all thecells within the network. This level of interaction clearly affects the complexity andcapability of the SON function, but does not really affect the use cases described here,

as each small cell interacts with the SON function, and what that SON function does(except in very broad terms) to arrive at the configuration or commands given to thesmall cells is outside the scope of this document.

2.2 SON features

The overall SON feature may be considered as a set of smaller features, some self-

contained, others interacting with each other. This section describes some of thoseconstituent SON features.

Self-configuration is defined as the process where newly deployed nodes are

configured by automatic installation procedures to get the necessary basicconfiguration for system operation.

This process works in pre-operational state. Pre-operational state is understood as thestate from when the small cell is powered up and has backbone connectivity until theRF transmitter is switched on.

As described in Figure 1-1, functions handled in the pre-operational state like:

•

Basic setup and


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• Initial radio configuration

are covered by the self configuration process.

An auto-configuration server (ACS) is defined as the entity that includes SON features

that enable the self-configuration process.

Self-optimization process is defined as the process where UE and small cellmeasurements and key performance metrics are used to auto-tune the network.

This process works in the operational state. The operational state is understood as thestate where the RF interface is switched on and the cell is providing service to users.

As described in Figure 1-1, functions handled in the operational state like:

• Optimization/adaptation

are covered by the self-optimization process.

Self-optimization function is defined as the entity or set of entities that enable theself-optimization processes. Self-healing (wherein the SON function attempts to

diagnose/repair malfunctioning small cells or optimize the network around a failedsmall cell) is also included under the self-optimization phase.


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Small Cell power on

( or cable connected )

(A ) Basic Setup

(B ) Initial Radio

Configuration

(C ) Optimization/ Adaptation

a- 1 : configuration of IP address

and detection of OAM

a- 2 : authentication of Small Cell

a- 3 : association to Small Cell GW

a- 4 : downloading of firmware

( and operational parameters )

b-2 : coverage/ capacity related

parameter configuration

b- 1 : neighbour list configuration

c- 1 : neighbour list optimisation

c- 2 : coverage and capacity control

Self- Configuration

(pre - operational state)

Self- Optimisation

( operational state )

self healingc-3 :

Figure 2-1 Overview of SON features

2.3 SON management

SON management is an important factor for heterogeneous deployments. The

operators are looking into a single point of management for their networkdeployments. It is important that operators are able to configure, manage, monitor,and upgrade both 3G and 4G devices based on assigned operator privileges anddifferent collection points (e.g., small cell RAN and/or EPC). The device functionalitymay provide the options that the performance parameters can be aggregated andcorrelated at the device level before they are forwarded to a management system inthe core. Thus the operators may monitor and manage the performance of each

enterprise small cell network that they offer. This may also bring the benefit of servicelevel agreements (SLAs) to a number of managed enterprise networks.

SON can cover large networks only in theory. Therefore, solution vendors workingtogether with operators must define a management framework for small cell SON


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deployment so that the operators have opportunity to manage, monitor and plan theirfuture network deployments. The SON management system should be able to reactand (re-)configure SON functions depending on the operator target application.

Figure 2-2 SON management


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3. Enterprise SON use cases

In the following sections the use cases are enumerated into specific categories. Specifically thetopics covered are configuration, planning, deployment and operation, optimization andmaintenance.

Care is taken to point out of the use case specifically applies to UMTS or LTE or both.

Where necessary, inter-frequency issues but within the same RAT are also highlighted.

3.1 Glossary of terms

Since the document and specifically sections to follow are heavy on acronyms, the followingglossary is added for convenience to the reader.

Acronym Term

ACS Auto-configuration server

ANR Automatic neighbor discoveryCN Core network

DL Downlink. From the base station to the user equipment

ECGI E-UTRAN cell global identifier

eNB e Node B (popular name for LTE base stations)

EPC Evolved packet core

IP Internet protocol

IT Information technology

LTE Long term evolution

MME Mobility management entity

MSC Mobile-network switching center

NB Node B (popular name for UMTS base station)NLM Network listen module (sometimes called a sniffer)

NRT Neighbor relations table

PCI Physical cell identifier (PCI in LTE)

PLMNID Public land-mobile network identifier

PSC Primary scrambling code (in UMTS)

S1 An LTE standards-defined interface between eNB and EPC. Has two ‘planes’. Auser plane and an MME plane.

SC Small cell

SGSN Serving GPRS support node

TNL Transport network layer

TX Transmit or transmitter

UL Uplink. From the user equipment to the base station

UMTS Universal mobile transmission system

X2 An LTE standards defined interface between eNBs.

Table 3-1 Glossary of terms


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3.2 Configuration

Overview A small cell is configured for initial operation

Actors Small cell, ACS, optional enterprise small cell gateway

Applicability LTE and UMTSPreconditions An enterprise with an existing enterprise small cell network or the

infrastructure to start one. The infrastructure includes (but not limited to) anACS server inside or outside its private network. Optionally, there is a gateway(that could be the enterprise edge router also) outside the private network

Flow 1. A new small cell is powered on and connected to the enterprise

network

2. The small cell is pre-configured with the ACS access parameters(Example: IP address and authentication credentials etc.)

3. The small cell connects to the ACS server and is authenticated, ifnecessary

4. The ACS server performs initial configurations. Examples of such aconfiguration include, but are not limited to, steps such as:

a.

New or updated customer specific firmware downloadb. A small cell configuration which could include network

parameters (PLMNID etc.), frequency list, initial transmitpower, PSC (UMTS) or PCI (LTE), IP addresses of gateway orEPC (LTE) etc., Initial list of neighbor relations if available, IPor access details for stand alone SON function, if necessary

5. Starting with the firmware available and using the data given, thesmall cell reaches a state where it can setup all the necessaryconnections and is authenticated as needed

6. At this point the small cell may invoke the SON function to adjust orupdate any of the initially configured parameters

7. The small cell starts its transmitter and reaches a valid operationalstate in which it is able to perform the radio specific operations for the

RAT(s) for which it is enabledUses

Notes(Optional)

The initial configuration is within the purview of the SON function logicallyintegrated in the ACS server or the EMS. Once in operation state, a SONfunction may gain control on many configuration and radio parameters

Table 3-2 Small cell initial configuration

Overview A existing small cell is assigned a new PCI (PSC) due to discovery of aPCI (PSC) conflict

Actors Small cell, ACS, SON function, optional enterprise small cell gateway, NLM

Applicability LTE and UMTS

Preconditions An enterprise with an existing enterprise small cell network having an ACS

server inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network

Flow 1. An existing small cell discovers a new neighbor and vice versa (through

A4 reporting etc.)

2. The SON function determines a PCI (PSC) conflict or confusion after theabove events

3. Based on the network topology and PCI (PSC) policies (such as the poolof PCIs (PSCs) available for the enterprise small cells), the SONfunction computes or selects a new PCI (PSC) value for one or moresmall cells to avoid the conflict

4. SON function conveys the new PCI (PSC) value(s) to the affected smallcell(s)

5. Each affected small cell performs the procedures needed to have the

new PCI (PSC) take effect


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Overview A existing small cell is assigned a new PCI (PSC) due to discovery of aPCI (PSC) conflict

6. Small cell updates its neighbors with the new PCI/PSC value (SONfunction informs the neighbors of the affected small cell with the newPCI/PSC value)

Uses

Notes(optional)

Table 3-3 PCI assignment and conflict resolution

3.3 Planning, deployment and operation

Overview A new small cell is added to an existing enterprise network

Actors New small cell (NB or eNB), ACS, SON function, optional enterprise small cellgateway, NLM


Preconditions An enterprise with an existing enterprise small cell network having an ACSserver. Optionally, there is a gateway (that could be the enterprise edge routeralso) outside the private network. If a new network is being commissioned thenthe ACS server is installed and initialized properly

Flow 1. The new small cell is connected to the enterprise private network

2. The small cell is provisioned (manual, script, or factory) with the ACSand optional stand alone SON function details (port, IP address andauthentication credentials)

3. Small cell connects to the ACS and SON function, is authenticated, andobtains its configuration from the ACS

4. Optionally, NLM is switched on and neighbor network parameters

(DL/UL frequencies, PCI or PSC, TX power etc.) are discovered andNLM data sent to SON function

5.

The SON function assigns radio parameters (PCI/PSC etc.) withconsideration also to any co-channel macro eNodeB that are visible to

the small cell (taking into consideration any policies provisioned intothe SON function)

6. The small cell connects to the CN or EPC elements (through theenterprise gateway or directly)

7. Optionally, the small cell performs TNL address resolution for NLM-discovered and ACS-provisioned neighbors

8. Optionally, the small cell establishes X2 or Iurh links to any neighbors

for which it has TNL addresses (whether discovered or provisioned)

9. The small cell transmitter is turned on and is operational

10. The SON function performs the ‘add a new neighbor’ sequence for eachsmall cell that it evaluates to have the small cell as a new neighbor

Uses Add a new neighborNotes

(optional)

Table 3-4 Adding a new small cell to an enterprise network

Overview Many new small cells are added to create a new enterprise network or

expand an existing one

Actors New small cells, ACS, SON function, optional enterprise small cell gateway,NLM, an IT or operator technician


Preconditions An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (that

could be the enterprise edge router, also) outside the private network


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Overview Many new small cells are added to create a new enterprise network orexpand an existing one

Flow 1. A technician determines the required number of small cells and their

locations within the enterprise.

2. This is done using general deployment guidelines and enterprise

building dimensions [1] 3. The small cells are provisioned with the ACS and optional stand alone

SON function details

4. Small cells connect to the ACS and optional stand alone SONfunction(s), are authenticated, and obtain their configuration from the

ACS.

5. As part of configuration, the small cells are configured to belong to acommon enterprise cluster and initialized to be in a training mode1.

6. Optionally, NLM is switched on and neighbor network parameters(DL/UL frequencies, PCI (PSC) etc.) are discovered and NLM data sentto SON Function(s).

7. SON function(s) can be reside in individual small cells, one small cell or

the ACS server.

8.

SON function(s) assign temporary or permanent radio parameters(e.g., PCI (PSC), with consideration also to any co-channel macro(e)NodeBs that are visible to the small cell (taking into consideration

any policies provisioned into the SON function).

9. The small cell connects to the MME (MSC and SGSN) in the EPC (CN)(through the enterprise gateway or directly)

10. Optionally, small cells perform TNL address resolution for NLM-discovered and ACS-provisioned neighbors or are provided by theirSON functions with neighbor address information.

11. Optionally, small cells establish X2 (Iurh) links to any neighbors forwhich TNL addresses are available (whether discovered or provisioned)

12. The small cell transmitters are turned on and small cells begin tooperate in training mode.

13.

The technician walks around the enterprise with a UE in connectedmode with the enterprise small cell network or some other tool tocollect information about RF environment in the enterprise (e.g., signalquality of the small cells, surrounding macros, etc.).

14. The collected information is either passed autonomously or withtechnician assistance to the SON function(s).

15. At the end of the walk-around, SON function(s) is instructed todetermine transmit power for the small cells.

16. SON function determines transmit power using obtained RF informationconsidering any co-channel macros and UL interference issues toprovide good coverage and capacity in the enterprise network.

17. Small Cells start radiating with the updated TX power and begin normaloperation.

18.

Optionally, technician performs additional walk-arounds to verifycoverage and mobility in the enterprise. Based on this second walk-

around, SON function(s) may raise alarms, error codes suggestingrequired changes in the deployment. In such a case, technician may re-do the calibration after taking remedial measures

Uses

Notes(optional)

Table 3-5 Adding many new small cells to an enterprise network

1 Training mode is defined as a state where a UE can camp and move to connected state and the small cell

is capable of receiving and processing Event and Measurement reports. Mobility functions etc. are notnecessarily enabled in this state


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Overview A small cell is decommissioned from an existing enterprise network

Actors Small cell, ACS/ON server, optional enterprise small cell gateway, NLM




Flow 1. A small cell is taken out of service using the ‘administratively taking asmall cell out of service’ procedure or needs to be decommissionedsince the cell is malfunctioning.

2. The SON function is informed by OAM procedure that the small cell isbeing permanently decommissioned

3. The SON function adds the re-usable resources back to the pool ifpossible (such as PCI (PSC))

4. The SON function updates NRT tables if under its control and informsthe remaining small cells

5. The SON function optionally instructs the remaining small cells toadjust TX power

6.

The remaining small cells start operating with the updated parametersUses Administratively taking a small cell out of service

Notes

(optional)

Table 3-6 Decommissioning a small cell from an enterprise network

Overview A small cell in an existing enterprise network is suspended from

operation by administratively locking it

Actors Small cell, ACS/SON server, optional enterprise small cell gateway, NLM


Preconditions An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (that

could be the enterprise edge router also) outside the private networkFlow 1. A small cell is instructed to power down by the ACS server setting its

administrative state to shutting down.

2. The small cell shuts down radio functions (not admitting new radiobearers or waiting for the sessions to end)

3. The small cell may inform the MME (small cell GW, MSC and SGSN) or

alternatively the enterprise small cell gateway

4. The small cell may inform the (e)NodeB or small cell with which it hasX2 (Iurh) connections

5. The small cell may inform any other auxiliary servers (e.g. PBX) thatare providing enterprise wide functions and need to know

6. The small cell informs the SON function and becomes administrativelyLocked.

7.

The SON function optionally instructs the remaining small cells toadjust TX power

8. The remaining small cells start operating with the updated parameters

Uses

Notes

(optional)

Table 3-7 Suspending a small cell from operation


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Overview A small cell is returned to normal operation from an administrativelylocked state in an existing enterprise network



Preconditions An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network

Flow 1. An administratively locked small cell is unlocked by the ACS

2. The small cell may inform the (e)NodeB or small cell with which it hasX2 (Iurh) connections

3. The small cell may inform the MME (small cell GW, MSC and SGSN) orenterprise small cell gateway as necessary

4. The small cell may inform any other auxiliary servers (e.g., PBX) thatare providing enterprise wide functions and need to know

5. The small cell turns on its transmitters

6. The SON function optionally instructs the remaining small cell to adjust

TX power or does a centralized computation and sends the new powers

7.

The remaining small cell start operating with the updated parametersUses

Notes(optional)

Table 3-8 Returning a suspended small cell to normal service

Overview A small cell in a network discovers a new neighbor using UEmeasurement report

Actors Small cell, ACS/SON server, optional enterprise small cell gateway, NLM,connected UE

Applicability LTE


server inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network. There isa UE in connected state to the small cell

Flow 1. A small cell in operation receives message from a UE (e.g., A4 even

message) it is serving containing a PCI value

2. The small cell determines, in comparison to its local NRT, that this is a

new PCI

3. The small cell requests the UE to report the ECGI of the newly reportedPCI

4. The ECGI also confirms a new neighbor

5. The small cell may optionally request the mobility configuration of thisnew neighbor from the ACS/EMS/SON server (e.g., whether activeand/or idle mode handoff is allowed)

6.

The small cell queries the MME or enterprise small cell gateway for TNLaddress resolution

7. The small cell establishes X2 connections as necessary

8. All small cell configurations (NRT) are updated synchronously

9. Any overhead message SIB that might need to be changed due to thisnew neighbor is also taken care of by the RRM

Uses

Notes(optional)

Table 3-9 Discovering a new neighbor in an LTE network


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Overview A small cell in a network along with ACS/SON server determines thatanother small cell (or macro) is no longer a neighbor



Preconditions An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network

Flow 1. A small cell in operation does not receive measurements regarding a

PCI (PSC)/(E)CGI for configurable period of time

2. Alternately the ACS server or SON function decommissions a small cell

3. The PCI (PSC)/(E)CGI need to be removed from the local and globalNRT

4. Optionally, the small cell is commanded by the ACS server or SONfunction to remove neighbor

5. The small cell tears down X2 (Iurh) connections if necessary

6. All small cell configurations (NRT) are updated synchronously

Uses

Notes(optional)

As a result of the NRT update, the small cell SIB messages may need to beupdated by RRM

Table 3-10 Deleting a neighbor in LTE and UMTS

3.4 Optimization

Overview Small cell transmit power is optimized by SON function

Actors An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network.


Preconditions Each small cell in the network has been pre-configured and operational. The

small cell may have gone through one or more rounds of assisted transmitpower and placement adjustments.

Flow 1. The small cell measures or tracks various L1/ L2/L3 metrics (for

example, load or handover statistics or RACH attempts etc.)

2. Small cell forwards the same to the SON function

3. SON function determines that a change in transmit power is necessary

4. SON function conveys the new transmit power value to the small cell

5. The small cell configuration is updated and any data synchronization orprocedure that are needed to switch to the new transmit power areinitiated – potentially with involvement from the ACS server or EMS

6. The small cell becomes operational with the new transmit power

Uses

Notes(optional)

Table 3-11 Optimization of small cell transmit power by SON function


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Overview Small cell and macro partition resources to help balance load andmanage interference

Actors Small cell, macro, ACS, SON function

Applicability LTE

Preconditions An enterprise with an existing enterprise small cell Network having an ACSserver inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network.Enterprise small cell(s) are deployed in the same frequency as macros. Fortime domain partitioning, macros and small cells need to operatesynchronously

Flow 1. SON function determines small cell is co-channel with macro (e.g., via NLMmeasurements, configuration parameters)

2. ACS or SON function determines resource partitioning pattern betweensmall cell and macro, and convey it to the macro and small cell. ACS orSON function may also determine configuration and control parameters,(for example, reporting periods, RSRP thresholds for eICIC/ICIC in macroand small cell)

3. Alternatively (to step 2),

a.

Small cell(s) establish X2 link to co-channel macro and exchange trafficload information with macro or SON function.

b. Macro or SON function determines the appropriate resource partitioningpattern and conveys to small cell or macro respectively.

4. Resource partitioning can be achieved by utilizing standard-definedprocedures in time domain (i.e., eICIC) and/or frequency domain (i.e.,ICIC).

5. The determination of partitioning pattern can be based on expected trafficload on macro and small cell, past traffic history, or some other

configuration policy.

6. Small cell follows the resource partitioning pattern for scheduling its users.

7. When multiple small cells are installed in an enterprise, small cells in theenterprise perform inter-small cell resource coordination within theresources available through resource coordination with macro.

8. An enterprise-SON function in the enterprise may act as X2 aggregator

and/or proxy for eICIC/ICIC message exchange between small cell andmacro

Uses

Notes

(optional)

Table 3-12 Load and interference management with macro network


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Overview Small cells in a network balance load

Actors Small cell, ACS, SON function


Preconditions An enterprise with an existing enterprise small cell Network having an ACS


Flow 1. Small cells in operation measure their own traffic load level (see Note 1)and report to the SON function.

2. SON function reviews load level of the small cells and determines if certainsmall cells are overloaded based on available air interface or backhaulresources.

3. SON function conveys its decision to small cells to perform SON activities.For example,

a. Adjust the handover parameters on small cells to offload some trafficfrom busy small cells to less busy neighboring small cell(s) (mobilityload balancing (MLB) (see Note 2))

b. Adjusting its coverage through transmit power adjustment.

c.

Adjusting cell selection/reselection thresholdsUses

Notes

(optional)

1. It is a normal RRM function to handle instantaneous overload by doing one

or more of the following:

a. stopping new user admission

b. reconfiguring existing bearers to reduce their load

c. termination of low priority user services to serve higher priority users

It is expected that RRM provides general load information as well asspecific overload information to the SON function to allow it to optimize theload handling of the set of small cells serving this enterprise. The SONFunction is expected to consider such load across many small cells on atimescale that is significantly longer than that of the instantaneousoverloads caused by individual service requests to individual small cells.

2.

Although from a 3GPP perspective MLB is LTE-specific, the equivalentactivity in UMTS can be achieved by the SON function adjusting thehandover parameters of the small cells through the ACS

Table 3-13 Load balancing


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Overview SON function optimizes for mobility robustness

Actors An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (that

could be the enterprise edge router also) outside the private network


Preconditions Small cells are operating and neighbor relations are already available. Handoffsare allowed between the small cells and, optionally, to and from the macronetwork (e)NodeBs. Small cells, locally or elsewhere, have aggregatedhandover metrics and KPI available (examples include radio link failures priorto or after handovers, ping-pong handovers, etc.)

Flow 1. Handover metrics and KPI are made available to SON function

2. Optionally, instantaneous and averaged radio environment metrics are alsoavailable to the SON function

3. Optionally, instantaneous and averaged load and resource usage metricsare available to SON functions

4. SON function decides to increase or decrease the handover footprint of asmall cell to other small cells in the same RAT, other RATs or to the macrothrough updated parameters (such as A3 frequency or cell specific offsets,time-to-trigger, etc.) as well as increase or decrease the chance of ping-pong through hysteresis parameter controls

5. The small cell configuration is updated if necessary and any datasynchronization or procedures that are needed to switch to the newparameters are initiated – potentially with involvement from the ACSserver or EMS

6. The small cell becomes operational with the new parameters

Uses

Notes

(optional)

Table 3-14 Mobility robustness optimization

Overview SON function optimizes RACH parameters

Actors An enterprise with an existing enterprise small cell network having an ACS



Preconditions Small cell is operational and has the ability to admit new users or allowhandovers from other small cell or the macro. Access metrics are availablelocally or centrally and optionally available to the SON function (averagenumber of preambles, average of open loop power for successful access etc.)

Flow 1. SON function aggregates access metrics

2. SON function determines to change RACH parameters to change RACHresources – for example, power ramping step and the maximum number of

preamble transmissions. In LTE, SON function may choose to change open-loop metrics for contention based access

3. New parameters are sent to the small cell

4. The small cell configuration is updated if necessary and any data

synchronization or procedures that are needed to switch to the newparameters are initiated – potentially with involvement from the ACSserver or EMS

5. The small cell becomes operational with the new parameters

6. Note that RACH parameter optimization may also be performed when smallcell Tx power is changed (e.g., for load balancing, coverage optimization).

Uses

Notes(optional)

Table 3-15 RACH optimization


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Overview Mobility robustness optimization between LTE and UMTS



Preconditions Multiple overlay deployments of LTE and/or UMTS small cells. An enterprise

with an existing enterprise small cell network having an ACS server inside oroutside its private network. Optionally, there is a gateway (that could be theenterprise edge router also) outside the private network

Flow 1. Small Cells in operation detect scenarios of handover failures (early

handover, late handover etc.,). These failures may be related to inter-frequency LTE/UMTS handovers or inter-RAT handovers between UMTS andLTE. These failures are reported to the SON function.

2. SON function reviews the failure information and determines if handoverparameters need to be modified.

3. SON function conveys its decision to small cells to perform SON activities

a. Adjust the related handover triggers on small cells to improve inter-RAT/inter-frequency handover performance

UsesNotes(optional)

Table 3-16 SON mobility robustness optimization between LTE and UMTS

Overview Load balancing between LTE and UMTS



Preconditions Multiple overlay deployments of LTE and/or UMTS small cells. An enterprisewith an existing enterprise small cell network having an ACS server inside or

outside its private network. Optionally, there is a gateway (that could be theenterprise edge router also) outside the private network

Flow 1.

Small cells in operation measure their own traffic load and interferencelevels and report to the SON function. The load reports and triggers may beseparately defined for inter-RAT/inter-frequency load balancingfunctionality.

2. SON function reviews RAT/frequency specific load information of the smallcells and determines if certain small cells are overloaded and/or heavily

interfered based on available air interface or backhaul resources.3. SON function conveys its decision to small cells to perform SON activities

a. Adjust the related inter-RAT/inter-frequency handover parameters onsmall cells to offload some traffic from busy small cells to less busysmall cell(s) on a different RAT

b. Adjust the related inter-RAT/inter-frequency cell reselection parameterson small cells to offload some traffic from busy small cells to less busy

small cell(s) on a different RAT

Uses

Notes

(optional)

Table 3-17 SON load balancing between LTE and UMTS


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3.5 Maintenance

Overview Registered agents PUSH/PULL SON metrics

Actors An enterprise with an existing enterprise small cell network having an ACSserver inside or outside its private network. Optionally, there is a gateway (thatcould be the enterprise edge router also) outside the private network. Agentsof various sorts that register with the SON function to receive SON metrics


Preconditions Agents are registered with the SON function and the interfaces are well known

Flow 1. SON function sends instantaneous or aggregated metrics (PM, CM, DM) to

agents that are registered to receive them

2. Optionally, the registered agent acknowledges receipt of the same

Uses

Notes(optional)

These agents might be instantiated for dashboarding or for providing real ornear-real time views to the service provider regarding the optimized operationand can be used as a basis for operator intervention or policy updates etc.

Table 3-18 Dissemination of SON metrics


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4. IT technician assisted SON

It was pointed out in the initial sections that in a very narrow sliver of contexts it is possible tobenefit from an IT technician’s involvement in the configuration and deployment of enterprise

Networks and assist the SON function. The use cases presented so far stand on their own andform the core of the SON functions. Here, the use cases that show the benefit of having an ITtechnician assist the SON function are given.

In the first section general use cases are enumerated while in the second section specificexamples are given. They are here to show how the use cases in section 4.1 will likely actuallybe used when combined with real architectures, parameter and algorithm choices.

While the overall document is informative – these are here for illustrative purposes. The goal isto show how the generic, technology and algorithm agnostic use cases in both Sections 3 andSection 4.1 of this document can be adopted to meet specific RAT, architecture, algorithmic andparametric choices while meeting the spirit and intent of the specific use case.

4.1 General use cases

Overview

Actors Enterprise small cell (NB or eNB), ACS, SON function, IT technician interface,IT technician

Applicability

Preconditions An enterprise with an existing enterprise small cell network having an

associated ACS and SON function(s). An IT technician interface with access tothe relevant sources of information for the enterprise and able to validate thecredentials of the IT technician

Flow 1. The IT technician interface is provisioned and all the needed connectivity isenabled

2. The interface aggregates SON function metrics from all registered SON

functions 3. The IT technician logs in to the IT technician interface, using any necessary

credentials for that enterprise.

4. The IT technician interface gathers any necessary instructions/information(or displays previously received instructions/information) from the SONfunction and elsewhere as required.

5. The IT technician interface displays any necessary instructions/informationto the IT technician

Uses

Notes

(optional)

The IT technician interface could be implemented in a variety of ways, using a

variety of technologies in a variety of places.

The actual user interface, as an example, might take the form of a dashboard

such as Figure 4-1 Example IT technician user interface with a list ofnotifications/actions and the ability to perform a number of operations

Table 4-1 Provisioning and use of IT technician interface


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Figure 4-1 Example IT technician user interface

Overview Small cell positions are optimized with help from an IT technician andto meet some desired optimization goal

Actors Enterprise small cell (NB or eNB), ACS, SON function, NLM, IT technicianinterface, IT technician


Preconditions An enterprise with an existing enterprise small cell network having anassociated ACS and SON function. Enterprise small cell network is in theoperational state, recording data and providing it to the SON function

Flow The SON function analyses data received from the small cells in the enterprisenetwork.

The SON function determines a physical movement or addition of a small cell isdesirable.

The SON function generates a physical change request notification to the ITTechnician.

The IT technician makes the physical change.

The SON function assesses the new arrangement of the enterprise network

Uses IT technician accesses IT technician interface

Notes(optional)

The physical placement of small cells in an enterprise network can be optimizedwith IT technician assistance. There are multiple potential criteria foroptimizing placement:

In the simple / initial case small cells should be evenly spread.

Small cells may need to be moved / added to provide additional capacity incertain areas of an enterprise.

Small cells may need to be moved / added as a result of a downlink powercalibration walk test (e.g. because the small cell-UE path-loss is too great).

Small cells may need to be moved / added according to other criteria, asdetermined by the SON function.

The use case illustrates a SON cycle where the small cells report information tothe SON function, which determines physical actions required and sendsrequests to perform these actions to the IT technician.

The SON function is not aware of the physical building layout and construction,nor the physical locations of small cells within the building; it therefore onlyknows of the relationships between small cells and macro cells from an RF /RAN point of view (inter-small cell path-loss determined by NLM, handoverstatistics, established X2 links, etc.). Therefore corresponding IT Technicianinstructions can also only be in relative terms such as: ‘Move SCx & SCy closertogether.’ or ‘Install an additional small cell near to SCz ’

Table 4-2 IT technician assisted optimization of small cell position

Prio Notification

Med Move small cell S/N 132334561 and smallcell S/N 132334561 apart

Med Move small cell S/N 132334561 and small

cell S/N 132339023 apart

Add small cell

Remove small cell

Welcome to the IT Technician Interface – Logged in as Andrew

Perform DownlinkPower Calibration


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Overview SON function requests or initiates an IT technician walk test with thegoal of optimizing some metric



Preconditions An enterprise with an existing enterprise small cell network having anassociated ACS and SON function

Flow 1. The SON function requests that the IT technician performs a walk test via

the IT technician interface

2. The IT technician initiates the walk test process from the IT technicianinterface

3. The IT technician interface collects sufficient information about the mobiledevice to be used, so that it can be identified by the enterprise small cells(*)

4. The IT technician interface informs the SON function that a walk test is

about to start, and the identifying information about the mobile to be used

5.

The SON function informs all small cells within the enterprise that a walktest is started and provides identifying information on the mobile to beused for the test

6. The SON function informs the IT technician interface that the enterprisesmall cell network is ready

7. The IT technician interface informs the IT technician that the test canbegin, giving any necessary instructions

8. The IT technician initiates a call/starts a streaming session, thensystematically walks the whole area covered by the enterprise small cellnetwork

9. During the test the enterprise small cells request and receive measurementreports from the IT technician’s mobile, at sufficiently granular timeintervals during the test

10.

Either during the test or at the end of the test, the enterprise small cellsdeliver the information determined from the mobile’s measurement reportsto the SON function

11. The IT technician completes his walk of the area and stops the downlinkpower calibration process

12. The SON function analyses the data collected from each small cell in theenterprise

13. The SON function generates requests/notifications to the IT technician ifrequired (e.g. to move / add small cells)



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Notes(optional)

There are situations, especially in larger enterprise deployments, where theoptimisation process can be greatly enhanced by an IT-technician walk-test.

For example:

• The path-loss between small cell and mobile is important, because toolarge a loss can cause uplink interference from the small cell-attached

mobile to surrounding macrocells• The pilot TX power required to overcome the macro signal is difficult to

accurately calibrate without information gathered from mobiles in thebuilding.

Because of the nature of enterprise deployments and the variations inenterprise buildings’ shape and construction, it is impossible to determine suchinformation purely from NLM information from small cells within the enterprise,so IT assistance is called on to help make the appropriate measurements

(*) The information to identify the test mobile to the small cells could be directlymobile-related, e.g., for 3G the mobile number or IMSI could be used, or it

could be session related, e.g., a test call number, streaming server

address/URL to be used or local APN services.

Reference: Enterprise femtocell deployment guidelines, section 5.4, section6.2.

Table 4-3 SON function initiated IT technician walk test


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4.2 Specific examples

Overview Small cell positions are optimized with help from an IT technician. Inthis example use case, the desired optimization goal is to evenly spreadthe small cells



Preconditions An enterprise with an existing enterprise small cell network having anassociated ACS and SON function. Minimum recommended inter-small cellpath-loss PLmin is defined. Maximum recommended inter-small cell path-lossPLmax is defined. The maximum number of technician actions to be performedin a single technician operation TAmax is defined by (this should be a smallnumber, e.g.3)

Flow 1. Each small cell in the enterprise network determines the path-loss for eachneighbor relationship (using NLM it compares the pilot channel transmitpower to received pilot power)

2.

The small cell reports the path-loss of each neighbor relationship to theSON function

3. The SON function ranks neighbor relationships by path-loss

4. If all neighbor-relationship path-loss values in the enterprise are greaterthan PLmax SON function raises ‘advise add additional small cell toenterprise network’ (or other necessary) notification to IT technician via ITtechnician interface

5. If any neighbor-relationship path-loss values in the enterprise are less thanPLmin then the SON function raises ‘Advise move enterprise small cellsfurther apart: Small SCa, SCb’ notifications for the TAmax smallest path-lossvalues less than PLmin via IT technician interface to IT technician

6. If there are no neighbor-relationship path-loss values in the enterprise lessthan PLmin but some neighbor-relationship path-loss values in theenterprise are greater than PL

max the SON function raises ‘Advise move

enterprise small cells closer together: SCa, SCb’ notifications for the TAmax largest path-loss values above PLmax via IT technician interface to IT

technician

7. IT technician takes action, according to any notifications he is given by theIT technician interface


Notes(optional)

In the simple/initial case, small cells in an enterprise network should be evenlyspread. After initial placement, or addition of small cells (or even internalchanges such as adding or removing partition walls) placement of small cellsmay not be even. This use case illustrates the SON process for optimizing smallcell placement based on inter-small cell path-loss, with support of the ITtechnician

The use case illustrates a SON cycle where the small cells report information to

the SON function, which determines physical actions required and sendsrequests to perform these actions to the IT technician

This uses case raises the following notifications to the IT technician interface:

Advise add additional small cell to enterprise network

Advise move enterprise small cells further apart: SCa, SCb

Advise move enterprise small cells closer together: SCa, SCb

Reference: Enterprise femtocell deployment guidelines, section 5.5

Table 4-4 IT technician assisted optimization of small cell position – even spread example


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Overview Example of a SON function initiated IT technician walk-test with UEpathloss optimization and downlink power optimization as thepreferred metric

Actors Enterprise small cell (NB or eNB), ACS, SON function, NLM, IT technician

interface, IT technician


Preconditions An enterprise with an existing enterprise small cell Network having anassociated ACS and SON function. Maximum recommended small cell to mobilepath-loss PLMmax is defined. Maximum cell-specific RS (CPICH) power differencebetween small cells in the enterprise network PDmax is defined.

Optimization of the small cell placement (use case ‘IT technician assistedoptimization of small cell Position’) has been iterated enough times that thereare no outstanding notifications relating to it

Flow 1. The SON function requests that the IT technician performs a downlinkpower calibration test (e.g. by sending a notification: ‘Perform downlinkpower calibration test’ via the IT technician interface)

2. The IT technician initiates the downlink power calibration process from theIT technician interface

3.

The IT technician interface collects sufficient information about the mobiledevice to be used, so that it can be identified by the enterprise smallcells(*)

4. The IT technician interface informs the SON function that a downlink powercalibration test is about to start, and the identifying information about themobile to be used

5. The SON function informs all small cells within the enterprise that thedownlink power calibration test is started and provides identifyinginformation on the mobile to be used for the test

6. The SON function informs the IT technician interface that the enterprisesmall cell network is ready.

7. The IT technician interface informs the IT technician that the test canbegin, giving any necessary instructions.

8.

The IT technician initiates a call/starts a streaming session, thensystematically walks the whole area covered by the enterprise small cellnetwork

9. During the test the enterprise small cells request and receive measurementreports from the IT technician’s mobile, sufficient to determine:

a. Mobile small cell path-loss

b. Signal quality information: Cell-specific RSRQ (CPICH Ec/Io) measuredat the mobile at sufficiently granular time intervals during the test

10. Either during the test or at the end of the test, the enterprise small cellsdeliver the information determined from the mobile’s measurement reportsto the SON function

11. The IT technician completes his walk of the area and stops the downlinkpower calibration process

12.

The SON function analyses the small cell mobile path-loss samplescollected from each small cell in the enterprise

13. The SON function determines which (if any) small cells have small cell

mobile path-loss greater then PLmax and ranks them (combination of mostsamples >PLmax and how much larger path-loss than PLmax was measured).For the small cell (if any) that is determined to be the worst, SON functionraises ‘Advise add additional small cell to enterprise network in vicinity ofSCa’ notification to the IT Technician interface

14. The SON function analyses the mobile cell-specific RSRQ (CPICH Ec/Io)samples collected from each small cell in the enterprise; the SON functiondetermines the pilot power required by each small cell to achieve minimumsignal quality Qmin, based on these samples

15. The SON function adjusts the cell-specific RS (CPICH) power accordingly,

within the constraint that the difference between pilot powers of small cells


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Overview Example of a SON function initiated IT technician walk-test with UEpathloss optimization and downlink power optimization as thepreferred metric

within the enterprise cannot exceed PDmax.


Notes(optional)

The path-loss to a mobile within the enterprise should not exceed maximumvalue PLMmax (85 dB in the Enterprise femtocell deployment guidelines [1]) inany circumstance; this is to avoid uplink noise rise at macro cell sites

Because of the nature of enterprise deployments and the variations in

enterprise buildings’ shape and construction, it is impossible to determine likelymobile/small cell path-loss purely from NLM information from small cells withinthe enterprise, so IT assistance is called on to help to measure this value

In addition, the required downlink pilot channel power required to successfullyovercome any macro signal present cannot be accurately determined basedpurely on NLM of the small cells and so again, IT assistance is called on tomake measurements to help determine enterprise small cell pilot channel

power values. The minimum signal quality Qmin is the value required (theEnterprise femtocell deployment guidelines refer to a value of -16dBm CPICHEc/Io). The maximum delta between pilot powers transmitted by all small cellsin the enterprise should not exceed PDmax (the Enterprise femtocelldeployment guidelines refer to a value of 10dB)

This uses case raises the following notifications to the IT technician interface:

Advise add additional small cell to enterprise network in vicinity of SCa

Perform downlink power calibration test

(*) The information to identify the test mobile to the small cells could be directlymobile-related, e.g. the mobile number or IMSI, or it could be session related,e.g., a test call number, streaming server address/URL or local APN to be used

Reference: Enterprise femtocell deployment guidelines, section 5.4, section 6.2

Table 4-5 SON function initiated walk test example: TX power calibration


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5. Summary

Enterprise deployments will be a key part of small cell deployments and therefore a key part ofsmall cell adoption and their success. SON functions are key in making the planning,

deployment, optimization and management of these networks so that they function the bestthey can. If solutions meet the use cases in this document, this goal can be met in the main.


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References

1 ‘Enterprise Femtocell Deployment Guidelines Femto Forum Working Group 2

Document’, April 8

th

2011, Femto Forum WG22 ‘LTE Self-Organizing Networks’, Seppo Hamalainen et al, Wiley3 ‘3GPP TS 32.500: Self-Organizing Networks: Concepts and requirements’, 3GPP4 ‘3GPP TR 25.913: Requirements for Evolved UTRA and Evolved UTRAN’, Version

9.0.0

son usecases

Documents