Anr management (e ran3.0 08)

ANR Management
eRAN3.0
Feature Parameter Description
Issue 08
Date 2013-05-20
HUAWEI TECHNOLOGIES CO., LTD.

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eRAN
ANR Management Contents
Issue 08 (2013-05-20) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
i
Contents
1 Introduction................................................................................................................................1-1
1.1 Scope ............................................................................................................................................ 1-1
1.2 Intended Audience......................................................................................................................... 1-1
1.3 Change History.............................................................................................................................. 1-1
2 Overview of ANR.......................................................................................................................2-1
2.1 Introduction.................................................................................................................................... 2-1
2.2 Benefits ......................................................................................................................................... 2-1
2.3 Architecture ................................................................................................................................... 2-1
3 Concepts Related to ANR .......................................................................................................3-1
3.1 Overview ....................................................................................................................................... 3-1
3.2 NCL ............................................................................................................................................... 3-1
3.3 NRT ............................................................................................................................................... 3-1
3.4 Blacklists ....................................................................................................................................... 3-2
3.4.1 HO Blacklist .......................................................................................................................... 3-2
3.4.2 X2 Blacklist ........................................................................................................................... 3-2
3.4.3 RRC Blacklist........................................................................................................................ 3-2
3.5 Whitelist......................................................................................................................................... 3-3
3.5.1 HO Whitelist.......................................................................................................................... 3-3
3.5.2 X2 Whitelist........................................................................................................................... 3-3
3.6 Abnormal Neighboring Cell Coverage........................................................................................... 3-3
3.7 ANR Capabilities of UEs ............................................................................................................... 3-3
4 Intra-RAT ANR............................................................................................................................4-1
4.1 Overview ....................................................................................................................................... 4-1
4.2 Intra-RAT Event-triggered ANR..................................................................................................... 4-1
4.2.1 Automatic Detection of Missing Neighboring Cells............................................................... 4-1
4.2.2 Automatic Maintenance of NCLs and NRTs ......................................................................... 4-4
4.2.3 Automatic Detection of Abnormal Neighboring Cell Coverage............................................. 4-5
4.3 Intra-RAT Fast ANR....................................................................................................................... 4-6
5 Inter-RAT ANR............................................................................................................................5-1
5.1 Overview ....................................................................................................................................... 5-1
5.2 Inter-RAT Event-triggered ANR..................................................................................................... 5-1
5.2.1 Automatic Detection of Missing Neighboring Cells............................................................... 5-1
5.2.2 Automatic Maintenance of NCLs and NRTs ......................................................................... 5-3
5.3 Inter-RAT Fast ANR....................................................................................................................... 5-4
6 ANR with Shared Cells ............................................................................................................6-1
6.1 Shared Neighboring Cell Broadcasting PLMN List in an RR Manner........................................... 6-1
6.2 Shared Neighboring Cell Not Broadcasting PLMN List in an RR Manner .................................... 6-2

eRAN
ii
7 Manual Management of Neighbor Relations .....................................................................7-1
7.1 Overview ....................................................................................................................................... 7-1
7.2 Adding or Removing a Neighbor Relation..................................................................................... 7-1
7.3 Blacklisting a Neighbor Relation ................................................................................................... 7-1
7.3.1 Configuring an HO Blacklist ................................................................................................. 7-1
7.3.2 Configuring an X2 Blacklist................................................................................................... 7-2
7.3.3 Configuring an RRC Blacklist ............................................................................................... 7-2
7.4 Whitelisting a Neighbor Relation................................................................................................... 7-3
7.4.1 Configuring an HO Whitelist ................................................................................................. 7-3
7.4.2 Configuring an X2 Whitelist .................................................................................................. 7-3
8 X2 Self-Setup..............................................................................................................................8-1
8.1 Overview ....................................................................................................................................... 8-1
8.2 X2 Self-Setup in X2 over S1 Mode ............................................................................................... 8-2
8.3 X2 Self-Setup in X2 over M2000 Mode......................................................................................... 8-4
8.4 eNodeB Configuration Update Based on X2 Messages............................................................... 8-6
9 Related Features.......................................................................................................................9-1
9.1 Intra-RAT ANR............................................................................................................................... 9-1
9.1.1 Required Features................................................................................................................ 9-1
9.1.2 Mutually Exclusive Features................................................................................................. 9-1
9.1.3 Affected Features ................................................................................................................. 9-1
9.2 Inter-RAT ANR............................................................................................................................... 9-1
9.3 X2 Self-Setup ................................................................................................................................ 9-1
10 Impact on the Network ........................................................................................................10-1
10.1 Intra-RAT ANR........................................................................................................................... 10-1
10.1.1 Impact on System Capacity.............................................................................................. 10-1
10.1.2 Impact on Network Performance...................................................................................... 10-1
10.2 Inter-RAT ANR........................................................................................................................... 10-1
10.3 ANR with Shared Cells.............................................................................................................. 10-2
10.4 X2 Self-Setup ............................................................................................................................ 10-2

eRAN
iii
11 Engineering Guidelines for Intra-RAT ANR....................................................................11-1
11.1 When to Use ANR ..................................................................................................................... 11-1
11.2 Information to Be Collected ....................................................................................................... 11-2
11.3 Network Planning ...................................................................................................................... 11-2
11.4 Overall Deployment Procedure ................................................................................................. 11-2
11.5 Deploying Intra-RAT ANR.......................................................................................................... 11-2
11.5.1 Deployment Procedure..................................................................................................... 11-2
11.5.2 Deployment Requirements ............................................................................................... 11-2
11.5.3 Data Preparation............................................................................................................... 11-2
11.5.4 Precautions....................................................................................................................... 11-3
11.5.5 Hardware Adjustment ....................................................................................................... 11-3
11.5.6 Feature Activation ............................................................................................................. 11-4
11.5.7 Activation Observation ...................................................................................................... 11-5
11.5.8 Reconfiguration................................................................................................................. 11-6
11.5.9 Deactivation ...................................................................................................................... 11-6
11.6 Monitoring.................................................................................................................................. 11-6
11.7 Parameter Optimization............................................................................................................. 11-6
11.8 Troubleshooting......................................................................................................................... 11-9
12 Engineering Guidelines for Inter-RAT ANR ...................................................................12-1
12.1 When to Use ANR ..................................................................................................................... 12-1
12.2 Information to Be Collected....................................................................................................... 12-1
12.4 Overall Deployment Procedure................................................................................................. 12-1
12.5 NoneDeploying Inter-RAT ANR................................................................................................. 12-1
12.5.2 Deployment Requirements............................................................................................... 12-1
12.5.3 Data Preparation .............................................................................................................. 12-1
12.5.4 Precautions....................................................................................................................... 12-2
12.5.6 Feature Activation............................................................................................................. 12-2
12.5.7 Activation Observation...................................................................................................... 12-3
12.5.8 Reconfiguration ................................................................................................................ 12-3
12.5.9 Deactivation...................................................................................................................... 12-3
12.6 Performance Optimization......................................................................................................... 12-4
13 Engineering Guidelines for ANR with Shared Cells....................................................13-1
13.1 When to Use ANR ..................................................................................................................... 13-1

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iv
13.5 Deploying ANR with Shared Cells............................................................................................. 13-1
13.5.4 Precautions....................................................................................................................... 13-2
13.5.9 Deactivation...................................................................................................................... 13-3
13.6 Performance Optimization......................................................................................................... 13-3
14 Engineering Guidelines X2 Automatic Management ..................................................14-1
14.5 Deploying X2 Self-Setup........................................................................................................... 14-1
14.5.4 Precautions....................................................................................................................... 14-2
14.5.9 Deactivation...................................................................................................................... 14-4
14.6 Monitoring.................................................................................................................................. 14-4
14.7 Parameter Optimization ............................................................................................................ 14-8
15 Parameters .............................................................................................................................15-1
16 Counters..................................................................................................................................16-1
17 Glossary..................................................................................................................................17-1
18 Reference Documents.........................................................................................................18-1

eRAN
ANR Management 1 Introduction
1-1
1 Introduction
1.1 Scope
This document describes the Automatic Neighbor Relation (ANR) management feature in terms of
implementation principles, parameter adjustments, feature dependencies, network impact, and
engineering guidelines.
The ANR management feature involves the following optional features:
 LOFD-002001 Automatic Neighbour Relation (ANR)
 LOFD-002002 Inter-RAT ANR
Any managed objects (MOs), parameters, alarms, or counters described in this document correspond to
the software release delivered with this document. In the event of updates, the updates will be described
in the product documentation delivered with the latest software release.
1.2 Intended Audience
This document is intended for:
 Personnel who need to understand ANR management
 Personnel who work with Huawei Long Term Evolution (LTE) products
1.3 Change History
This section provides information about the changes in different document versions.
There are two types of changes, which are defined as follows:
 Feature change: refers to a change in the ANR management feature of a specific product version.
 Editorial change: refers to a change in wording or the addition of information that was not described in
the earlier version.
Document Issues
The document issues are as follows:
 08 (2013-05-20)
 07 (2013-03-15)
 06 (2013-02-27)
 05 (2012-12-29)
 04 (2012-09-20)
 03 (2012-06-30)
 02 (2012-05-11)
 01 (2012-03-30)
 Draft A (2012-01-10)
08 (2013-05-20)
Compared with issue 07 (2013-03-15) of eRAN3.0, issue 08 (2013-05-20) of eRAN3.0 includes the
following changes.

eRAN
1-2
Change Type Change Description Parameter Change
Feature
change
None None
Editorial
change
Revised descriptions of the procedure for detecting
missing neighboring cells by using UE history
information. For details, see "Detecting Missing
Neighboring Cells by Using UE History Information" in
section 4.2.1 "Automatic Detection of Missing
Neighboring Cells."
None
Added descriptions of using the DRX mechanism to read
ECGIs or CGIs of neighboring cells during intra-RAT or
inter-RAT ANR measurements. For details, see
"Detecting Missing Neighboring Cells by Using
Event-triggered UE Measurements" in section 4.2.1
"Automatic Detection of Missing Neighboring Cells" and
section 5.2.1 "Automatic Detection of Missing
Neighboring Cells."
None
Deleted descriptions of DRX being required for intra-RAT
and inter-RAT ANR. For details, see sections 9.1.1
"Required Features" and 9.2.1 "Required Features."
(During intra-RAT and inter-RAT ANR measurements,
reading CGIs of neighboring cells using the DRX
mechanism does not require the activation of the DRX
feature.)
None
Added the section 8.4 "eNodeB Configuration Update
Based on X2 Messages."
None
07 (2013-03-15)
following changes.
Feature change None None
Editorial change  Modified the flow chat for X2 self-setup.
For details, see Figure 8-2 and Figure
8-3.
 Added the description that both the
source and target eNodeBs can send the
X2 Setup Request message during X2
self-setup. For details, see section 8.2
"X2 Self-Setup in X2 over S1 Mode" and
section 8.3 "X2 Self-Setup in X2 over
M2000 Mode."
None

eRAN
1-3
06 (2013-02-27)
following changes.
Editorial change Revised descriptions in chapter 6
"ANR with Shared Cells."
None
05 (2012-12-29)
following changes.
Feature change Added X2 self-setup. For details,
see the following chapters or
sections:
 8 "X2 Self-Setup"
 9.3 "X2 Self-Setup"
 10.4 "X2 Self-Setup"
 14 "Engineering Guidelines X2
Automatic Management"
Added the following parameters:
 GlobalProcSwitch.X2SonLinkSetupType
 GlobalProcSwitch.X2SonSetupSwitch
 X2SigIP.LOCIP
 X2eNodeB.FIRSTSIGIP
Editorial change Moved the license control ID. None
04 (2012-09-20)
following changes.
Editorial change Revised some descriptions. For details, see sections
11.5.6 "Feature Activation", 12.5.6 "Feature Activation"
and13 "Engineering Guidelines for ANR with Shared
Cells."
None
03 (2012-06-30)
following changes.

eRAN
1-4
Feature change Added the function of ANR with
shared cells.
For details about the principles, see
chapter 6 "ANR with Shared Cells."
For details about the impact on the
network, see section 10.3 "ANR with
Shared Cells."
For details about engineering
guidelines, see chapter 11
"Engineering Guidelines."
Added the
ENodeBAlgoSwitch.RanSharingAnrSwitch
parameter.
Editorial change Revised some descriptions. For
details, see section 7.3.1 "Configuring
an HO Blacklist."
None
02 (2012-05-11)
following changes.
Editorial change Revised some descriptions in the document. None
01 (2012-03-30)
This is the first official release.
Compared with draft A (2012-01-10) of eRAN3.0, issue01 (2012-03-30) of eRAN3.0 includes the
following changes.
Editorial change Revised the engineering guidelines. For details,
see chapter 11 "Engineering Guidelines."
None
Draft A (2012-01-10)
Compared with draft A (2011-07-15) of eRAN2.2, draft A (2012-01-10) of eRAN3.0 includes the following
changes.
Feature change Removed TempNRTs. None

eRAN
1-5
Modified the mechanism for adding a
newly detected external neighboring cell to
an NCL.
Modified the mechanism for adding a
neighbor relation to an NRT.
For details, see "Automatic Maintenance of
NCLs" and "Automatic Maintenance of
NRTs" in section 4.2.2 "Automatic
Maintenance of NCLs and NRTs."
Deleted the AddCellThd parameter.
Modified the mechanism for removing an
external cell from an NCL.
Modified the mechanism for removing a
neighbor relation from an NRT.
For details, see "Automatic Maintenance of
NCLs" and "Automatic Maintenance of
NRTs" in section 4.2.2 "Automatic
Maintenance of NCLs and NRTs."
Changed the default value of the
ANR.DelCellThd parameter.
Added the following parameters:
 ANR.StatisticPeriodForNRTDel
 ANR.StatisticNumForNRTDel
Modified the conditions for starting fast
ANR.
Changed the default value of the
ANR.FastAnrRprtInterval parameter.
Editorial change Optimized the engineering guidelines. None
Moved the information about PCI conflict
detection to a new document named PCI
Conflict Detection and Self-Optimization.
None

eRAN
ANR Management 2 Overview of ANR
2-1
2 Overview of ANR
2.1 Introduction
Operation and maintenance (OM) of the radio access network has become increasingly complex,
difficult, and costly because of the large number of network elements, the implementation of different
system standards, and the coexistence of different equipment vendors and telecom operators. To
address this situation, the self-organizing network (SON) concept is proposed. The main functions of
SON are self-configuration, self-optimization, and self-healing.
ANR is a self-optimization function. It automatically maintains the integrity and effectiveness of neighbor
cell lists (NCLs) and neighbor relation tables (NRTs) to increase handover success rates and improve
network performance. In addition, ANR does not require manual intervention, which reduces the costs of
network planning and optimization.
Neighbor relations are classified as normal and abnormal. Abnormal neighbor relations exist in the
cases of missing neighboring cells, physical cell identifier (PCI) conflicts, abnormal neighboring cell
coverage, and unstable neighbor relations. ANR automatically detects missing neighboring cells, PCI
conflicts, and abnormal neighboring cell coverage, and maintains neighbor relations.
Based on neighbor relations, ANR is classified into intra-RAT ANR and inter-RAT ANR. Based on the
methods of measuring neighboring cells, ANR is classified into event-triggered ANR and fast ANR (also
known as periodic ANR). RAT is short for radio access technology. Figure 2-1 shows ANR
classifications.
Figure 2-1 ANR classifications
2.2 Benefits
Intra-RAT ANR handles neighbor relations with E-UTRAN cells, while inter-RAT ANR handles neighbor
relations with GERAN, UTRAN, and CDMA2000 cells. Here, UTRAN, E-UTRAN, GERAN, and
CDMA2000 are short for universal terrestrial radio access network, evolved UTRAN, GSM/EDGE radio
access network, and code division multiple access 2000, respectively.
2.3 Architecture
To implement ANR, the eNodeB collaborates with UEs and the M2000.

eRAN
ANR Management 3 Concepts Related to ANR
3-1
3 Concepts Related to ANR
3.1 Overview
This chapter describes basic ANR-related concepts, which include NCL, NRT, HO blacklist, X2 blacklist,
HO whitelist, X2 whitelist, radio resource control (RRC) blacklist, and abnormal neighboring cell
coverage.
3.2 NCL
The NCLs of an eNodeB contain information about the external cells of the eNodeB. The external cells of
an eNodeB are provided by base stations other than the eNodeB.
NCLs are classified into intra-RAT NCLs and inter-RAT NCLs. Each eNodeB has one intra-RAT NCL and
multiple inter-RAT NCLs.
 The intra-RAT NCL records the ECGIs, PCIs, and E-UTRA absolute radio frequency channel numbers
(EARFCNs) of the external E-UTRAN cells.
 The GERAN NCL records the cell IDs, base transceiver station identity codes (BSICs), and ARFCNs
of the external GERAN cells.
 The UTRAN NCL records the cell IDs, scrambling codes, and UTRA ARFCNs (UARFCNs) of the
external UTRAN cells.
 The CDMA2000 NCL records the cell IDs, frequencies, and PCIs of the external CDMA2000 cells.
NCLs are used as a basis for creating neighbor relations. The eNodeB adds newly detected external
cells to NCLs. External cells can be automatically managed (for example, added, deleted, or modified)
by ANR.
3.3 NRT
The NRTs of a cell contain information about the neighbor relations between a cell and its neighboring
cells. NRTs are classified into intra-RAT NRTs and inter-RAT NRTs. Each cell has one intra-RAT
intra-frequency NRT, one intra-RAT inter-frequency NRT, and multiple inter-RAT NRTs. The intra-RAT
intra-frequency NRT and intra-RAT inter-frequency NRT are referred to as the intra-RAT NRT in this
document.
Table 3-1 shows an example of the NRT. The information in this table is for reference only.
Table 3-1 An example of the NRT
SN LCI Target Cell PLMN eNodeB ID Cell ID Removal Control Handover
Control
1 LCI#1 46001 eNodeB ID#1 Cell ID#1 Prohibited Prohibited
2 LCI#1 46001 eNodeB ID#2 Cell ID#2 Allowed Allowed
3 LCI#1 46001 eNodeB ID#3 Cell ID#3 Prohibited Prohibited
NOTE
For details about the NRT, see section 22.3.2a in 3GPP TS 36.300 V10.3.0 (2011-03). Huawei NRT does not include the
attribute that controls whether to allow X2 setup.
NRT structures are the same for intra- and inter-eNodeB neighbor relations. Intra-eNodeB neighbor relations only exist in
NRTs, not in NCLs.

eRAN
3-2
The NRT in Table 3-1 is an intra-RAT NRT. An inter-RAT NRT differs greatly from an intra-RAT NRT.
The NRT contains the following information, which can be updated automatically or manually:
 Local cell identifier (LCI): uniquely identifies the source cell in a neighbor relation. This attribute is
defined by Cell.LocalCellId.
 Target cell PLMN: identifies the PLMN of the operator that owns the target cell.
 eNodeB ID: identifies the eNodeB that provides the target cell.
 Cell ID: identifies the target cell.
 Removal control: indicates whether a neighbor relation can be removed from the NRT by ANR. By
default, this attribute is set to allow removal. It can also be set to prohibit removal.
 Handover control: indicates whether this neighbor relation can be used for a handover. By default, this
attribute is set to allow handover. It can also be set to prohibit removal.
NRTs can be managed (for example, added, deleted, or modified) automatically by ANR.
NOTE
eRAN3.0 eNodeBs maintain only NRTs, whereas eNodeBs of earlier versions maintain both NRTs and TempNRTs.
3.4 Blacklists
3.4.1 HO Blacklist
An HO blacklist contains the information about neighbor relations that cannot be used for a handover or
removed automatically from the NRT by ANR. The neighbor relations in the HO blacklist must meet the
following conditions:
 Removal control = prohibited
 Handover control = prohibited
A neighbor relation can be added to the HO blacklist manually. For details, see section 5.2 in 3GPP TS
32.511 V10.0.0 (2011-03).
3.4.2 X2 Blacklist
An X2 blacklist contains information about the neighboring eNodeBs with which the local eNodeB is not
allowed to set up X2 interfaces. If an X2 interface has been set up between the local eNodeB and a
neighboring eNodeB on the X2 blacklist, the interface will be removed automatically.
NOTE
To remove an X2 interface, the eNodeB removes the X2 logical connection but retains the configuration data for the X2
interface. This ensures that the configuration data is not lost due to exceptions such as misoperations.
3.4.3 RRC Blacklist
An RRC blacklist contains the neighboring E-UTRAN cells whose information will not be measured and
reported to the eNodeB by UEs. You can manually add an intra- or inter-frequency neighboring cell to an
RRC blacklist.

eRAN
3-3
3.5 Whitelist
3.5.1 HO Whitelist
An HO whitelist contains the information about neighbor relations that can be used for a handover but
cannot be removed automatically from the NRT by ANR. The neighbor relations in the HO whitelist must
meet the following conditions:
 Removal control = prohibited
 Handover control = allowed
A neighbor relation can be added to the HO whitelist manually. For details, see section 5.2 in 3GPP TS
32.511 V10.0.0 (2011-03).
3.5.2 X2 Whitelist
An X2 whitelist contains information about the neighboring eNodeBs with which the local eNodeB has
set up X2 interfaces. These X2 interfaces cannot be removed automatically.
3.6 Abnormal Neighboring Cell Coverage
Abnormal neighboring cell coverage may exist between intra-frequency E-UTRAN cells. As shown in
Figure 3-1, assume UEs in cell A detect signals from cell B. Then, ANR considers cell B to be a
neighboring cell of cell A and adds related information to an NCL or NRT. However, from a topology
perspective, the two cells do not meet the requirements for neighbor relations. In this situation, the
coverage of cell B is regarded as abnormal. This type of coverage is also called coverage overlap.
Figure 3-1 Abnormal neighboring cell coverage
The coverage of neighboring cells may be abnormal in any of the following scenarios:
 The antenna tilt or orientation changes because of improper installation or a natural phenomenon such
as strong wind.
 In mountainous terrain, the signals of the umbrella cell cover lower cells.
3.7 ANR Capabilities of UEs
The ANR capabilities of a UE refer to the ability of the UE to read the ECGIs of neighboring cells.
According to section B.1 in 3GPP TS 36.331 V10.1.0 (2011-03), the Feature Group Indicators bit string
contained in the UE Capability Information message indicates the ANR capability of the UE. Table 3-2
provides the definitions and setting descriptions of the ANR-related indicators.

eRAN
3-4
Table 3-2 Definitions and setting descriptions of the ANR-related indicators
Indicator
Index
Supported Functions (When the Indicator
Is Set to 1)
Remarks Applicability
5  Long discontinuous reception (DRX) cycle
 DRX command Media Access Control
(MAC) element
N/A Yes
16  Reporting of non-ANR-related periodical
intra-frequency measurements
 Reporting of non-ANR-related periodical
inter-frequency measurements is supported
if indicator 25 is also set to 1
 Reporting of non-ANR-related periodical
measurements of the UTRAN, GERAN,
CDMA2000 1xRTT, or CDMA2000 HRPD is
supported if indicator 22, 23, 24, or 26 is
also set to 1
NOTE
Non-ANR-related periodical measurements are the
measurements with trigger type and purpose set
to periodical and reportStrongestCells,
respectively. Event-triggered periodical
measurements are the measurements with trigger
type and reportAmount set to event and a value
greater than 1, respectively. Reporting of
event-triggered periodical measurements is a
mandatory function of event-triggered reporting
and therefore is not denoted by this indicator.
N/A Yes
17  Reporting of SON-related or ANR-related
periodical measurements
 Reporting of ANR-related intra-frequency
events
This indicator can only
be set to 1 when
indicator 5 is set to 1.
Yes
18 Reporting of ANR-related inter-frequency
events
This indicator can only
be set to 1 when
Yes (unless the UE
only supports band
13)
19 Reporting of ANR-related inter-RAT events This indicator can only
be set to 1 when
N/A
NOTE
In the preceding table, if an Applicability cell is marked with Yes, the functions mentioned in the Supported Functions
(When the Indicator Is Set to 1) cell have been implemented and successfully tested on the eNodeB.

eRAN
ANR Management 4 Intra-RAT ANR
4-1
4 Intra-RAT ANR
4.1 Overview
This chapter describes the optional feature LOFD-002001 Automatic Neighbour Relation (ANR).
Intra-RAT ANR is classified into intra-RAT event-triggered ANR and intra-RAT fast ANR. Intra-RAT
event-triggered ANR detects missing neighboring cells by using event-triggered UE measurements or
UE history information. In addition, it detects abnormal neighboring cell coverage and maintains
neighbor relations. For details, see section 4.2 "Intra-RAT Event-triggered ANR".
Based on the reporting of periodic UE measurements, intra-RAT fast ANR obtains information about all
possible intra-RAT neighboring cells before a handover is performed. This reduces the negative effects
of event-triggered UE measurements on handover performance. For details, see section 4.3 "Intra-RAT
Fast ANR."
4.2 Intra-RAT Event-triggered ANR
Intra-RAT event-triggered ANR is controlled by the IntraRatEventAnrSwitch check box under the
ENodeBAlgoSwitch.AnrSwitch parameter. The intra-RAT event-triggered ANR function is activated
when the IntraRatEventAnrSwitch check box is selected.
Intra-RAT event-triggered ANR detects missing intra-RAT neighboring cells and abnormal neighboring
cell coverage, and maintains neighbor relations. For details, see the following sections in this chapter.
4.2.1 Automatic Detection of Missing Neighboring Cells
The procedure for using event-triggered UE measurements to detect missing neighboring cells is
defined in section 22.3.2a in 3GPP TS 36.300 V10.3.0 (2011-03).
ANR can detect missing neighboring cells by using UE history information in addition to even-triggered
UE measurements.
Detecting Missing Neighboring Cells by Using Event-triggered UE
Measurements
Intra-RAT event-triggered ANR detects cells with unknown PCIs based on the intra- and inter-frequency
measurement reports that contain information about cells meeting the handover requirements.
Assume that cell A and cell B are involved in a handover. The UE is under the coverage of cell A of the
source eNodeB, and cell B is a neighboring cell of cell A.
Table 4-1 lists the identification information about cell A and cell B.
Table 4-1 Identification information about cell A and cell B
Cell PCI ECGI
Cell A 3 17
Cell B 5 19

eRAN
4-2
Figure 4-1 shows how the eNodeB detects cell B by using event-triggered UE measurements.
Figure 4-1 Procedure for detecting a missing intra-RAT neighboring cell by using event-triggered UE
measurements
The procedure is described as follows:
1. The source eNodeB delivers the inter-frequency measurement configuration to the UE, instructing
the UE to measure inter-frequency neighboring cells that work on the frequencies specified in the
measurement configuration.
NOTE
The UE performs intra-frequency neighboring cell measurements by default. When a UE establishes radio bearers, the
eNodeB delivers by default the intra-frequency neighboring cell measurement configuration to the UE by using the RRC
Connection Reconfiguration message. Therefore, if the UE needs to perform inter-frequency neighboring cell
measurements, the eNodeB must deliver the inter-frequency neighboring cell measurement configuration to the UE and
activate the measurement gap mode. For details about intra- and inter-frequency handover measurements, see Mobility
Management in Connected Mode Feature Parameter Feature.
2. The UE detects that the PCI of cell B meets the measurement requirements, and reports the PCI to
the source eNodeB. Note that the UE does not report the PCIs of the neighboring cells in the RRC
blacklist to the eNodeB.
3. The source eNodeB checks whether its intra-RAT NCL includes the PCI of cell B. If so, the procedure
ends. If not, the source eNodeB sends the measurement configuration to the UE, instructing the UE
to read the ECGI, tracking area code (TAC), and PLMN ID list of cell B.
4. The source eNodeB allows the UE to read these parameters over the broadcast channel (BCH).
NOTE
During intra-RAT ANR measurement, the eNodeB sends a set of temporary DRX parameters to a UE. Then, both the
eNodeB and UE enter the DRX state. During sleep time, the UE reads the ECGIs of neighboring cells. Then, the eNodeB
and UE exit the DRX state. Note that reading ECGIs of neighboring cells using the DRX mechanism does not require the
DRX feature to be activated. For details about how DRX is used in intra-RAT ANR measurements, see DRX Feature
Parameter Description.

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4-3
The maximum time that a UE can spend on ECGI reading is controlled by timer T321. The following table defines T321 as
quoted directly from section 7.3 in 3GPP TS 36.331 V10.1.0 (2011-03).
Timer Start Stop At Expiry
T321 Upon receiving measConfig
including a reportConfig with
the purpose set to reportCGI
Upon acquiring the information
needed to set all fields of
cellGlobalId for the requested cell,
upon receiving measConfig that
includes removal of the
reportConfig with the purpose set to
reportCGI
Initiate the measurement
reporting procedure, stop
performing the related
measurements and
remove the
corresponding measId
5. The UE reports the parameter values to the source eNodeB.
The source eNodeB adds the newly detected neighboring cell (cell B) to the intra-RAT NCL and adds the
neighbor relation to the intra-RAT NRT of cell A.
Detecting Missing Neighboring Cells by Using UE History Information
During a handover, the source eNodeB sends UE history information to the target eNodeB. Figure 4-2
shows the procedure for detecting a missing intra-RAT neighboring cell by using UE history information.
NOTE
UE history information consists of information about all the cells that have provided services for the UE. Defined in section
9.2.1.42 of 3GPP TS 36.413 V10.1.0 (2011-03) and section 9.2.38 of 3GPP TS 36.423 V10.1.0 (2011-03), this information
includes:
 ECGI of the last visited cell
 Type of the last visited cell
 Duration of the UE for camping on the cell
Figure 4-2 Procedure for detecting a missing neighboring cell based on UE history information
1. The source eNodeB sends a Handover Request message to the target eNodeB.

eRAN
4-4
2. The target eNodeB obtains the UE history information from the message. The target eNodeB checks
whether the ECGI of the last visited cell (in this case, cell A, the source cell) is in the NCL of the target
eNodeB and then proceeds as follows:
 If the ECGI is in the NCL but is not in the NRT, the target eNodeB adds the neighbor relation to the
NRT and the procedure ends.
 If the ECGI is not in the NCL, the target eNodeB reports the ECGI of cell A to the M2000. The
procedure goes to step 3.
3. The M2000 queries the PCI, TAC, and PLMN ID list of cell A based on the reported ECGI and sends
the parameters to the target eNodeB.
4. The target eNodeB adds cell A to its intra-RAT NCL.
NOTE
eRAN3.0 eNodeBs do not manage TempNRTs. Therefore, upon detecting a missing neighboring cell by using
event-triggered UE measurements or using UE history information, an eRAN3.0 eNodeB adds this neighbor relation
directly to the NRT. For details about how NRTs are maintained, see section 4.2.2 "Automatic Maintenance of NCLs and
NRTs."
4.2.2 Automatic Maintenance of NCLs and NRTs
Automatic maintenance of NCLs and NRTs ensures the effectiveness of neighbor relations and therefore
significantly improves network performance.
To enable automatic removal of intra-RAT neighbor relations, select the IntraRatAnrAutoDelSwitch
check box under the ENodeBAlgoSwitch.AnrSwitch parameter.
When a network is unstable or in the early stage of deployment, you are advised to disable this
automatic removal by clearing the IntraRatAnrAutoDelSwitch check box. The purpose is to prevent
frequent NCL/NRT updating and to complete the collection of neighbor relations as soon as possible.
NOTE
During intra-RAT neighbor relation addition through ANR, attributes that cannot be obtained through measurement reports
or UE history information use default values.
Automatic Maintenance of NCLs
During automatic maintenance of NCLs, the eNodeB can automatically add a newly detected external
neighboring cell to or remove an external cell from an NCL:
 The eNodeB automatically adds a cell to an NCL in either of the following cases:
− The eNodeB detects a missing neighboring cell based on UE measurements and receives
information about this cell, including the ECGI, TAC, and PLMN ID list.
− The eNodeB detects a missing intra-RAT neighboring cell based on UE history information
 The eNodeB automatically removes an external cell from an NCL if the following conditions are all met:
− The IntraRatAnrAutoDelSwitch check box under the ENodeBAlgoSwitch.AnrSwitch parameter is
selected. External cells can be automatically removed from NCLs only when this check box is
selected.
− The measurement period, which equals four times the value of ANR.StatisticPeriodForNRTDel, has
elapsed.
− The NRTs of all cells under the local eNodeB do not contain any neighbor relations with this external
cell.
− No X2 interface has been set up between the local eNodeB and the eNodeB of this external cell.

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4-5
Automatic Maintenance of NRTs
During automatic maintenance of NRTs, the eNodeB can automatically add a neighbor relation to or
remove a neighbor relation from an NRT:
 The eNodeB automatically adds a neighbor relation to an NRT if the eNodeB detects a missing
neighboring cell based on UE measurements, receives information about this cell, and adds this
information to the NCL.
 The eNodeB automatically removes a neighbor relation (for example, with cell A) from an NRT if the
IntraRatAnrAutoDelSwitch check box under the ENodeBAlgoSwitch.AnrSwitch parameter is
selected, the removal control flag is set to allow removal, and either of the following criteria is met:
Criterion 1, which includes the following two conditions:
− Within a measurement period specified by the ANR.StatisticPeriodForNRTDel parameter, the total
number of all types of handover from the local cell to its neighboring cells is greater than or equal to
the value of ANR.StatisticNumForNRTDel.
− In the same measurement period, cell A's PCI has never been included in any handover
measurement reports in the same measurement period.
Criterion 2, which includes the following two conditions:
− Within a measurement period specified by the ANR.StatisticPeriod parameter, the number of
handovers from each of the cells under the eNodeB to cell A is greater than or equal to the value of
ANR.NcellHoStatNum.
− In the same measurement period, the handover success rate is less than or equal to the value of
ANR.DelCellThd.
Note that when conditions in criterion 2 are met, not only is the neighbor relation with cell A removed
from the NRT, but also information about cell A is removed from the NCL.
4.2.3 Automatic Detection of Abnormal Neighboring Cell Coverage
Abnormal neighboring cell coverage may exist between intra-frequency E-UTRAN cells. Abnormal
neighboring cell coverage decreases the handover success rate because of the abnormal neighbor
relations it causes. Therefore, detecting and eliminating abnormal neighboring cell coverage plays an
important role in network optimization.
If the IntraRatEventAnrSwitch check box is selected, automatic detection of abnormal neighboring cell
coverage is activated. When the M2000 receives an operator's request to query the information about
abnormal neighboring cell coverage, it triggers the algorithm for detecting abnormal neighboring cell
coverage and listing abnormal neighboring cells.
The M2000 checks for abnormal neighboring cell coverage based on the latitudes and longitudes of the
serving cell and its neighboring cells. Then, the M2000 collects statistics about abnormal neighboring
cell coverage and generates a list of abnormal neighboring cells for the serving cell.
NOTE
The algorithm for automatically detecting abnormal neighboring cell coverage requires that the longitudes and latitudes of
the associated eNodeBs and sectors be accurately set and that the settings have taken effect. If the longitudes and
latitudes are not set or the settings do not meet the requirement, the detection results may not be accurate.
To view abnormal neighboring cells, perform the following steps:
Step 1 Log in to the M2000.
Step 2 Choose Configuration > LTE Self Optimization > ANR Management.
Step 3 On the Neighbor Cell Management tab page, view abnormal neighboring cells in the Query
Cross-Coverage Cell pane.

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4-6
----End
4.3 Intra-RAT Fast ANR
Intra-RAT fast ANR enables the eNodeB to quickly obtain information about all qualified neighboring
cells based on periodic UE measurements. This reduces the adverse impact of event-triggered UE
measurements on handover performance.
Intra-RAT fast ANR is enabled if the IntraRatFastAnrSwitch check box is selected.
Before UEs perform handovers, they periodically send measurement reports so that the eNodeB learns
about all neighboring cells whose reference signal received power (RSRP) values are greater than or
equal to the value of ANR.FastAnrRsrpThd.
After intra-RAT fast ANR is enabled, the eNodeB randomly selects fast-ANR-capable UEs to perform
intra- and inter-frequency measurements. After receiving periodic measurement reports from these UEs,
the eNodeB adds missing neighboring cells to NCLs. The procedure for detecting a missing neighboring
cell using fast ANR is the same as that using event-triggered ANR based on UE measurements, which is
detailed in "Detecting Missing Neighboring Cells by Using Event-triggered UE Measurements" in section
4.2.1 "Automatic Detection of Missing Neighboring Cells." However, after detecting a missing
neighboring cell, the eNodeB operation differs. In fast ANR, this newly detected neighboring cell is
added immediately only to the NCL. The neighbor relation will be added to the NRT only after a
successful handover from the serving cell to this neighboring cell.
Periodic UE measurements negatively affect the uplink throughput of the network. Therefore, intra-RAT
fast ANR restricts the number of concurrent UEs involved in intra-RAT periodic measurements. When
the number of involved UEs reaches the upper limit, the eNodeB does not select a new UE for periodic
measurements until a UE stops periodic measurements. The upper limit is specified by the
ANR.FastAnrIntraRatMeasUeNum parameter.
Periodic UE measurements also increase the power consumption of a UE. Therefore, intra-RAT fast
ANR restricts the number of periodic measurement reports by each UE. When the number of periodic
measurement reports by a UE reaches the upper limit, the UE stops periodic measurements so that the
eNodeB can select another UE for periodic measurements. This is repeated until the eNodeB
deactivates intra-RAT fast ANR. The upper limit is specified by the ANR.FastAnrRprtAmount
parameter. The interval for UEs to report periodic measurements is specified by the
ANR.FastAnrRprtInterval parameter.
The total number of neighboring cells that meet the RSRP requirement is limited, and periodic UE
measurements negatively affect the uplink throughput of the network. Therefore, intra-RAT fast ANR
restricts the total number of UEs involved in intra-RAT periodic measurements. At a regular interval,
specified by the ANR.FastAnrCheckPeriod parameter, the eNodeB checks whether the total number of
involved UEs is greater than the upper limit. The upper limit is specified by the
ANR.FastAnrIntraRatUeNumThd parameter. If yes, the eNodeB automatically deactivates intra-RAT
fast ANR. If no, periodic UE measurements continue.

eRAN
4-7
Process
Figure 4-3 shows an intra-RAT fast ANR process.
Figure 4-3 Intra-RAT fast ANR process
In summary, an intra-RAT fast ANR process is as follows:
1. After intra-RAT fast ANR is activated, the eNodeB starts a check period (ANR.FastAnrCheckPeriod)
and selects UEs to perform intra- and inter-frequency measurements to detect the PCIs of unknown

eRAN
4-8
cells. The number of UEs that can be selected is specified by the
ANR.FastAnrIntraRatMeasUeNum parameter.
2. During the check period, the eNodeB operates as follows:
− If the PCI of an unknown cell is reported, the eNodeB adds the information of this cell to the NCL,
sets the number of UEs that have performed measurements in the check period to 0, and then
selects UEs to perform measurements. The number of UEs that can be selected is also specified by
the ANR.FastAnrIntraRatMeasUeNum parameter. Fast ANR does not select VoIP users to perform
fast ANR measurements.
− If no PCI is reported, the eNodeB proceeds to the end of the check period.
3. At the end of each check period, the eNodeB performs the following operations:
− If the total number of UEs involved in intra- and inter-frequency measurements exceeds the value of
ANR.FastAnrIntraRatUeNumThd, the eNodeB enters the monitoring state. In this state, the
eNodeB monitors whether the PCI of an unknown cell is reported in an event-triggered ANR
measurement report. If an unknown PCI is reported during the monitoring state, the eNodeB starts
fast ANR measurements again.
− If the total number of UEs involved in intra- and inter-frequency measurements is less than or equal
to the value of ANR.FastAnrIntraRatUeNumThd, the eNodeB directly starts the next round of fast
ANR measurements.
During a fast ANR procedure, after a UE reports the PCI of an unknown cell, the eNodeB will instruct the
UE to read the ECGI of the cell. After the UE reports the ECGI of the cell, the eNodeB adds the
information about this cell to the NCL. Then, after a successful handover from the serving cell to this cell,
the eNodeB adds the neighbor relation to the NRT. For details about automatic maintenance of NCLs
and NRTs, see section 4.2.2 "Automatic Maintenance of NCLs and NRTs."
Impact on System Performance
Generalized from intra-RAT fast ANR, fast ANR includes two UE-performed processes: periodical PCI
reporting and CGI reading. In the periodical PCI reporting process, the UE periodically reports the PCI of
the neighboring cell with the best signal quality. In the CGI reading process, the UE reads the CGIs of
unknown cells.
 Periodical PCI reporting
− With respect to intra-frequency fast ANR, this process does not impact UE throughput, because the
UE does not need to listen to extra frequencies to perform intra-frequency measurements.
− With respect to inter-frequency or inter-RAT fast ANR, this process impacts UE throughput because
gap-assisted measurements are used. Two measurement gap patterns are defined in section 8.1.2 of
3GPP TS 36.133 V10.2.0 (2011-04): pattern 0 and pattern 1. They are described in Table 4-2. To
accelerate measurements, patter 0 is used by default.
Table 4-2 Gap patterns
Measurement
Gap Pattern
Gap Width (Unit: ms) Gap Repetition
Period (Unit: ms)
Target RAT
0 6 40  Inter-Frequency FDD E-UTRAN
 Inter-Frequency TDD E-UTRAN
 FDD UTRAN
 GERAN
 TDD low chip rate (LCR)
 CDMA2000 HRPD
 CDMA2000 1X

eRAN
4-9
Measurement
Gap Pattern
Gap Width (Unit: ms) Gap Repetition
Period (Unit: ms)
Target RAT
1 6 80  Inter-Frequency FDD E-UTRAN
 Inter-Frequency TDD E-UTRAN
 FDD UTRAN
 GERAN
 TDD LCR
 CDMA2000 HRPD
 CDMA2000 1X
 CGI reading
This process impacts all fast ANR processes. To read the CGI of an unknown cell, the UE needs to
listen to system information block type 1 (SIB1) of the unknown cell to obtain the PLMN ID, CGI, and
TAC of the cell. After obtaining this information, the UE must report it to the local eNodeB. The reading
and reporting processes decrease UE throughput.
In conclusion, fast ANR impacts system performance as follows:
 With respect to intra-frequency fast ANR, periodical PCI reporting does not impact system
performance, whereas CGI reading interrupts UE services.
 With respect to inter-frequency and inter-RAT fast ANR, periodical PCI reporting impacts UE
throughput, and CGI reading interrupts UE services.
NOTE
For details about the process in which a UE reads the ECGI of a neighboring cell, see "Detecting Missing Neighboring
Cells by Using Event-triggered UE Measurements" in section 4.2.1 "Automatic Detection of Missing Neighboring Cells."

eRAN
ANR Management 5 Inter-RAT ANR
5-1
5 Inter-RAT ANR
5.1 Overview
This chapter describes the optional feature LOFD-002002 Inter-RAT ANR.
Inter-RAT ANR is classified into inter-RAT event-triggered ANR and inter-RAT fast ANR.
Inter-RAT event-triggered ANR automatically detects missing neighboring inter-RAT cells by means of
event-triggered UE measurements. Inter-RAT fast ANR automatically detects missing neighboring cells
by instructing UEs to perform periodic measurements. Inter-RAT fast ANR enables eNodeBs to collect
neighboring cell information before handovers. This, to some degree, protects handover performance
from the adverse effects of inter-RAT event-triggered ANR measurements by UEs during handovers.
5.2 Inter-RAT Event-triggered ANR
Inter-RAT event-triggered ANR is enabled if the GeranEventAnrSwitch or UtranEventAnrSwitch
check box under the ENodeBAlgoSwitch.AnrSwitch parameter is selected.
After inter-RAT event-triggered ANR is activated, the eNodeB delivers inter-RAT measurement
configurations to the UE and instructs the UE to perform periodic measurements on neighboring GERAN
or UTRAN cells.
NOTE
Information about neighboring CDMA cells can be collected only by inter-RAT fast ANR. CDMA cells include CDMA2000
High Rate Packet Data (HRPD) cells and CDMA2000 1x Radio Transmission Technology (CDMA2000 1xRTT) cells.
Inter-RAT ANR does not check for PCI conflicts and abnormal neighboring cell coverage because of the following
reasons:
 The E-UTRAN has only a small number of standardized interfaces with other RATs.
 It is complex for the E-UTRAN to detect anomalies in other RATs.
5.2.1 Automatic Detection of Missing Neighboring Cells
This section describes how inter-RAT event-triggered ANR detects a missing neighboring UTRAN cell.
Assume that cell A is an E-UTRAN cell and cell B is a UTRAN cell. The UE is under the coverage of cell
A, and cell B is an inter-RAT neighboring cell of cell A.
Figure 5-1 shows how the eNodeB detects cell B by using event-triggered UE measurements.

eRAN
5-2
Figure 5-1 Procedure for detecting a missing inter-RAT neighboring cell by using event-triggered UE
measurements
1. The source eNodeB delivers the inter-RAT measurement configuration (including target RATs and
ARFCNs) to the UE, activates the measurement gap mode, and instructs the UE to measure the
neighboring cells that meet the measurement requirements.
NOTE
For details about inter-RAT handover measurements, see Mobility Management in Connected Mode Feature Parameter
Feature.
2. The UE detects that cell B meets the measurement requirements and reports its scrambling code to
cell A. If the NCL of the source eNodeB includes the scrambling code of cell B, the procedure ends. If
the NCL of cell A does not include the scrambling code of cell B, the source eNodeB proceeds to the
next step.
3. The source eNodeB requests the UE to read the parameters of cell B. If cell B is a GERAN or UTRAN
cell, the parameters to be read are the CGI, location area code (LAC), and routing area code (RAC).
4. The source eNodeB schedules appropriate call gapping to allow the UE to read the CGI and other
parameters of cell B over the BCH.
5. The UE reports the CGI and other parameters of cell B to the source eNodeB.
NOTE
During inter-RAT ANR measurement, the eNodeB sends a set of temporary DRX parameters to a UE. Then, both the
eNodeB and UE enter the DRX state. During sleep time, the UE reads the CGIs of neighboring cells. Then, the eNodeB
and UE exit the DRX state. Note that reading CGIs of neighboring cells using the DRX mechanism does not require the
DRX feature to be activated. For details about how DRX is used in inter-RAT ANR measurements, see DRX Feature
Parameter Description.
The source eNodeB adds the newly detected neighboring cell to its inter-RAT NCL and adds the
neighbor relation to the inter-RAT NRT.

eRAN
5-3
5.2.2 Automatic Maintenance of NCLs and NRTs
Automatic maintenance of NCLs and NRTs ensures the effectiveness of neighbor relations, which
improves network performance.
To enable automatic removal of neighbor relations with UTRAN, GERAN, or CDMA2000, select the
UtranAutoNrtDeleteSwitch, GeranAutoNrtDeleteSwitch, or CdmaAutoNrtDeleteSwitch check box
under the ENodeBAlgoSwitch.AnrSwitch parameter. When a network is unstable or in the early stage
of deployment, you are advised to disable automatic removal by clearing these check boxes. The
purpose of disabling automatic removal is to prevent frequent NCL/NRT updates so the collection of
neighbor relations can be completed as quickly as possible. Information about the external cells of a RAT
can be removed from the NCL and neighbor relations with the RAT can be automatically removed from
the NRT only when the corresponding check box is selected.
NOTE
The UtranAutoNrtDeleteSwitch, GeranAutoNrtDeleteSwitch, and CdmaAutoNrtDeleteSwitch check
boxes under the ENodeBAlgoSwitch.AnrSwitch parameter control the automatic removal of neighbor relations with
UTRAN, GERAN, and CDMA2000, respectively.
During inter-RAT neighbor relation addition through ANR, attributes that cannot be obtained through measurement reports
or UE history information use default values.
Automatic Maintenance of NCLs
During automatic maintenance of NCLs, the eNodeB can automatically add a newly detected external
neighboring cell to or remove an external cell from an NCL:
 The eNodeB adds a detected external neighboring cell to an NCL if the eNodeB detects a missing
neighboring cell based on UE measurements and receives information about this cell (including the
CGI).
 The eNodeB automatically removes an external cell from an NCL if all of the following conditions are
met:
− The UtranAutoNrtDeleteSwitch, GeranAutoNrtDeleteSwitch, or CdmaAutoNrtDeleteSwitch
check box under the ENodeBAlgoSwitch.AnrSwitch parameter is selected.
− The measurement period, which equals four times the value of ANR.StatisticPeriodForNRTDel, has
elapsed.
− The NRTs of all cells under the local eNodeB do not contain any neighbor relations with this external
cell.
Automatic Maintenance of NRTs
During automatic maintenance of NRTs, the eNodeB can automatically add a neighbor relation to or
remove a neighbor relation from an NRT:
 The eNodeB automatically adds a neighbor relation to an NRT if the eNodeB detects a missing
neighboring cell based on UE measurements, receives information about this cell, and adds this
information to the NCL.
 The eNodeB automatically removes a neighbor relation from an NRT when the corresponding check
box under the ENodeBAlgoSwitch.AnrSwitch parameter is selected and all of the following
conditions are met:
− The number of neighbor relations in the NRT has reached the maximum specification and a new
neighbor relation is to be added to the NRT.
− Within a measurement period specified by the ANR.StatisticPeriodForNRTDel parameter, the
number of handovers from the local cell to its inter-RAT neighboring cells is greater than or equal to
the value of ANR.StatisticNumForNRTDel. A group of neighboring cells that have the removal

eRAN
5-4
control flag set to allow removal have never been measured as the target cell of these handovers. In
this case, the eNodeB randomly removes a neighboring cell in this group from the NRT.
NOTE
Automatic removal of neighbor relations with CDMA2000 is not yet a requirement; therefore, it is not implemented in
eRAN3.0.
5.3 Inter-RAT Fast ANR
Inter-RAT fast ANR is enabled if the GeranFastAnrSwitch, UtranFastAnrSwitch, or
CdmaFastAnrSwitch check box under the ENodeBAlgoSwitch.AnrSwitch parameter is selected.
After inter-RAT fast ANR is activated, the eNodeB delivers inter-RAT measurement configurations to the
UE and instructs the UE to perform periodic measurements on neighboring GERAN, UTRAN, and CDMA
cells.
The principles of inter-RAT fast ANR are almost the same as those of intra-RAT fast ANR. For details
about the principles and relevant parameter settings, see section 4.3 "Intra-RAT Fast ANR."
For fast ANR with UTRAN and CDMA2000, the information element (IE) reportStrongestCellsForSON is
configured on the eNodeB for fast ANR measurements. According to section 6.3.5 in 3GPP TS 36.331
V10.1.0 (2011-03), when the measurement type is set to reportStrongestCellsForSON, reportAmount
can only be set to 1, which means that the UE sends only one measurement report to the eNodeB at one
time. In this case, the user-defined measurement period does not take effect. For the UE to periodically
transmit measurement reports, the fast ANR algorithm sets and sends reportStrongestCellsForSON to
the UE at an unconfigurable period.
In terms of parameters, inter-RAT fast ANR differs from intra-RAT fast ANR in the following ways:
 The signal quality threshold used to determine whether to periodically report a neighboring cell's PCI is
determined by the ANR.FastAnrRsrpThd parameter in intra-RAT fast ANR and by the following
parameters in inter-RAT fast ANR.
Target RAT Parameter Determining the Signal Quality Threshold
UTRAN ANR.FastAnrRscpThd
GERAN ANR.FastAnrRssiThd
CDMA2000 1xRTT ANR.FastAnrCdma1xrttPilotThd
CDMA2000 HRPD ANR.FastAnrCdmahrpdPilotThd
 The upper limit on the number of concurrent UEs involved in fast ANR measurements is specified by
the ANR.FastAnrInterRatMeasUeNum parameter in inter-RAT fast ANR and by the
ANR.FastAnrIntraRatMeasUeNum parameter in intra-RAT fast ANR.
 The upper limit on the total number of concurrent UEs involved in fast ANR measurements is specified
by the ANR.FastAnrInterRatUeNumThd parameter in inter-RAT fast ANR and by the
ANR.FastAnrIntraRatUeNumThd parameter in intra-RAT fast ANR.
Inter-RAT fast ANR has the same impact on network performance as intra-RAT fast ANR. For details,
see section 4.3 "Intra-RAT Fast ANR."

eRAN
ANR Management 6 ANR with Shared Cells
6-1
6 ANR with Shared Cells
Currently, the ANR with shared cells function automatically sets up neighbor relations with E-UTRAN
cells that are shared by PLMNs. In this chapter, neighboring cells refer to neighboring E-UTRAN cells
unless otherwise stated.
If a neighboring cell is shared by PLMNs and broadcasts its PLMN list in a round robin (RR) manner, a
UE in its serving cell might not be able to obtain the correct serving PLMN list of the neighboring cell. If
the shared neighboring cell does not broadcast its PLMN list in an RR manner, a UE in its serving cell
might not report a complete PLMN list of the neighboring cell to the serving cell. As a result of either case,
neighbor relations cannot be correctly added. To solve this problem, the serving cell can request that the
M2000 send the serving PLMN list of the neighboring cell. This solution works if the serving and
neighboring cells are managed by the same M2000, which stores the configuration data and status
information about the neighboring cell.
NOTE
eRAN3.0 does not support ANR with shared UTRAN or GERAN cells.
6.1 Shared Neighboring Cell Broadcasting PLMN List in an RR
Manner
ANR with shared cells that broadcast PLMN lists in an RR manner requires that
NBSLTEPLMNRoundSwitch under the ENodeBAlgoSwitch.RanSharingAnrSwitch parameter be
turned on.
If NBSLTEPLMNRoundSwitch is turned on and the serving eNodeB of a UE receives a measurement
report containing the CGI (PLMN ID+eNodeB ID+cell ID) of a neighboring cell, the serving eNodeB
reports the PCI and CGI obtained by the UE to the M2000. The M2000 queries the primary PLMN and
serving PLMN list of the neighboring cell based on the PCI, eNodeB ID, and cell ID. The M2000 then
sends the query result to the serving eNodeB. The serving eNodeB adds the PLMN information to the
external cell configuration and PLMN list configuration corresponding to the neighboring cell.
In a handover procedure, as shown in Figure 6-1, if cell A (the source cell) is shared by PLMNs and the
target eNodeB providing cell B detects from UE history information that cell A has not been configured as
a neighboring cell of cell B, the target eNodeB adds the information about cell A to the intra-RAT NCL.
The target eNodeB also adds the information about the secondary operators of cell A to the PLMN list
configurations of the external cell for cell B.

eRAN
ANR Management 6 ANR with Shared Cells
6-2
Figure 6-1 Procedure for detecting a missing neighboring cell based on UE history information
NOTE
If serving cells and neighboring cells are not managed by the same the NMS, the PLMN round function and ANR functions
are mutually exclusive when ENodeBSharingMode.EnodeBSharingMode is set to SHARED_FREQ.
6.2 Shared Neighboring Cell Not Broadcasting PLMN List in an
RR Manner
ANR with shared cells that do not broadcast PLMN lists in an RR manner requires that
NBSLTERANSharingSwitch under the ENodeBAlgoSwitch.RanSharingAnrSwitch parameter be
turned on.
If NBSLTERANSharingSwitch is turned on and NBSLTEPLMNRoundSwitch is turned off, and if the
serving eNodeB of a UE receives a measurement report containing the CGI of a neighboring cell, the
serving eNodeB takes one of the following actions:
 If the UE reports the PLMN list of the neighboring cell, the serving eNodeB starts a normal ANR
procedure.
After the UE reports the CGI and PLMN list to the serving eNodeB, the serving eNodeB adds the
information about the missing neighboring cell to the intra-RAT NCL and NRT and adds the PLMN
information to the PLMN list configurations.
 If the UE does not report the PLMN list of the neighboring cell, the serving eNodeB adds the
information about the missing neighboring cell to the intra-RAT NCL and NRT and reports the CGI
obtained by the UE to the M2000. The M2000 queries the PLMN list of the neighboring cell and sends
the query result to the serving eNodeB. The serving eNodeB adds the PLMN information to the PLMN
list configurations.
If the eNodeB detects a missing neighboring cell based on the UE history information, the eNodeB adds
the neighboring cell according to the same procedure described in section 6.1 "Shared Neighboring Cell
Broadcasting PLMN List in an RR Manner."

eRAN
ANR Management 7 Manual Management of Neighbor Relations
7-1
7 Manual Management of Neighbor Relations
7.1 Overview
Generally, neighbor relations are managed by ANR automatically. In some cases, they need to be
managed manually.
The manual management tasks are as follows:
 Adding or removing a neighbor relation
 Blacklisting a neighbor relation
 Whitelisting a neighbor relation
The latest manually maintained neighbor relations are kept in NRTs.
7.2 Adding or Removing a Neighbor Relation
To manually add or remove a neighbor relation, configure the corresponding managed objects (MOs), as
listed in the following table.
To Add or Remove a Neighbor Relation with... Configure the MO...
Intra-frequency E-UTRAN cell EutranIntraFreqNCell
Inter-frequency E-UTRAN cell EutranInterFreqNCell
UTRAN cell UtranNCell
GERAN cell GeranNcell
CDMA2000 1xRTT cell Cdma20001XRTTNcell
CDMA2000 HRPD cell Cdma2000HrpdNcell
For details, see Mobility Management in Connected Mode Feature Parameter Description.
If ANR is activated, neighbor relations are added or removed automatically.
7.3 Blacklisting a Neighbor Relation
7.3.1 Configuring an HO Blacklist
HO blacklists can only be configured manually. If an NRT contains a neighbor relation that has been
included in an HO blacklist, this neighbor relation cannot be automatically removed from the NRT.
A neighbor relation needs to be added to an HO blacklist in some special cases, for example, if the
neighbor relation causes coverage overlap and leads to unstable handovers.
To blacklist a neighbor relation, perform the following steps:
Step 3 On the Neighbor Cell Management tab page, select a neighbor relation to be blacklisted in the
Neighboring Cell pane.

eRAN
7-2
Step 4 Set both Deletion Prohibited and Handover Prohibited to TRUE in the displayed Set dialog
box.
----End
Alternatively, to blacklist a neighbor relation, you can set the EutranInterFreqNCell.NoHoFlag
parameter to FORBID_HO_ENUM and the EutranInterFreqNCell.NoRmvFlag parameter to
FORBID_RMV_ENUM. Depending on the neighbor relation type, these two parameters belong to
different MOs:
 For a neighbor relation with an intra-frequency E-UTRAN cell, they belong to the
EutranIntraFreqNCell MO.
 For a neighbor relation with an inter-frequency E-UTRAN cell, they belong to the
EutranInterFreqNCell MO.
 For a neighbor relation with a UTRAN cell, they belong to the UtranNCell MO.
 For a neighbor relation with a GERAN cell, they belong to the GeranNcell MO.
 For a neighbor relation with a CDMA2000 HRPD cell, they belong to the Cdma2000HrpdNCell MO.
 For a neighbor relation with a CDMA2000 1xRTT cell, they belong to the Cdma20001XRTTNCell MO.
7.3.2 Configuring an X2 Blacklist
X2 blacklists can only be configured manually.
An X2 blacklist contains information about the neighboring eNodeBs with which the local eNodeB is not
allowed to set up X2 interfaces. If an X2 interface has been set up between the local eNodeB and a
neighboring eNodeB on the X2 blacklist, the interface will be removed automatically.
NOTE
To remove an X2 interface, the eNodeB removes the X2 logical connection but retains the configuration data for the X2
interface. This ensures that the configuration data is not lost due to exceptions such as misoperations.
X2 blacklists can be configured as required by operators. For example, X2 setup between different base
station models is prohibited.
To configure an X2 blacklist, perform the following steps:
Step 3 Click the X2 Management tab on the ANR Management tab page.
----End
Alternatively, you can use the X2BlackWhiteList MO to configure an X2 blacklist.
7.3.3 Configuring an RRC Blacklist
UEs are not allowed to measure or be handed over to the cells contained in RRC blacklists. To configure
intra- or inter-frequency RRC blacklists, configure the IntraFreqBlkCell and InterFreqBlkCell MOs.

eRAN
7-3
7.4 Whitelisting a Neighbor Relation
7.4.1 Configuring an HO Whitelist
HO whitelists can only be configured manually. If an NRT contains a neighbor relation that has been
included in an HO whitelist, this neighbor relation cannot be automatically removed from the NRT for a
handover.
HO whitelists are especially useful in the early phase of network construction. In this phase, there are
usually a small number of UEs. Therefore, the best practice to collect neighbor relation information as
soon as possible is to prohibit ANR from automatically removing neighbor relations.
To whitelist a neighbor relation, perform the following steps:
Step 3 On the Neighbor Cell Management tab page, select a neighbor relation to be whitelisted in the
Neighboring Cell pane.
Step 4 Set Deletion Prohibited to TRUE and Handover Prohibited to FALSE in the displayed Set
dialog box.
----End
Alternatively, to whitelist a neighbor relation, you can set the EutranInterFreqNCell.NoHoFlag
parameter to PERMIT_HO_ENUM and the EutranInterFreqNCell.NoRmvFlag parameter to
FORBID_RMV_ENUM. Depending on the neighbor relation type, these two parameters belong to
different MOs:
 For a neighbor relation with an intra-frequency E-UTRAN cell, they belong to the
EutranIntraFreqNCell MO.
 For a neighbor relation with an inter-frequency E-UTRAN cell, they belong to the
EutranInterFreqNCell MO.
 For a neighbor relation with a UTRAN cell, they belong to the UtranNCell MO.
 For a neighbor relation with a GERAN cell, they belong to the GeranNcell MO.
 For a neighbor relation with a CDMA2000 HRPD cell, they belong to the Cdma2000HrpdNCell MO.
 For a neighbor relation with a CDMA2000 1xRTT cell, they belong to the Cdma20001XRTTNCell MO.
7.4.2 Configuring an X2 Whitelist
X2 whitelists can only be configured manually.
An X2 whitelist is especially useful when it takes a long time to maintain an eNodeB. During the
maintenance, the eNodeB cannot provide any services, and the NRTs of this eNodeB and its
surrounding eNodeBs may change. To avoid this situation, you can add the associated eNodeBs to the
X2 whitelist.
To configure an X2 whitelist, perform the following steps:

eRAN
7-4
Step 3 Click the X2 Management tab on the ANR Management tab page.
----End
Alternatively, you can use the X2BlackWhiteList MO to configure an X2 whitelist.

eRAN
ANR Management 8 X2 Self-Setup
8-1
8 X2 Self-Setup
8.1 Overview
This chapter describes the principles of X2 self-setup, which is implemented by the optional feature
LOFD-002004 Self-configuration.
In E-UTRAN, X2 interfaces exist between neighboring eNodeBs. The X2 interfaces allow some
messages to be directly exchanged between neighboring eNodeBs, which meets the requirements of a
flat LTE network architecture.
An X2 interface can be set up in either link configuration mode or end point configuration mode.
Figure 8-1 shows the classifications of X2 setup modes.
Figure 8-1 X2 setup modes
The X2 setup modes are described as follows:
 Link configuration mode
Users configure control-plane bearers (SCTP links) and user-plane bearers (IP paths) and negotiate
port information about the local eNodeB and peer eNodeB.
 End point configuration mode (also called self-setup mode)
After users configure ports, the eNodeBs automatically set up control-plane bearers (SCTP links) and
user-plane bearers (IP paths) for the X2 interface between the eNodeBs.
In end point configuration mode, the X2 self-setup procedure varies depending on whether the
neighboring eNodeB has been manually configured using an X2eNodeB MO.
− X2 self-setup with X2eNodeB manually configured
The eNodeB can set up an X2 interface based on the X2eNodeB MO. One X2eNodeB MO is used
to set up one X2 interface; therefore, multiple X2eNodeB MOs are required to set up multiple X2
interfaces.
− X2 self-setup with X2eNodeB automatically configured

eRAN
8-2
If X2eNodeB is not manually configured, the eNodeB can set up an X2 interface in X2 over S1 or X2
over M2000 mode. The mode is specified by the GlobalProcSwitch.X2SonLinkSetupType
parameter.
Both self-setup modes require that neighboring cell information be configured and that the X2
self-setup switch (specified by the GlobalProcSwitch.X2SonSetupSwitch parameter) be set to
ON(On). After a handover is triggered, the source eNodeB and target eNodeB can obtain the
configuration information about each other. Based on the information, the X2 interface between the
two eNodeBs is automatically set up.
NOTE
X2 self-setup reduces configuration operations by users. Users need only to configure the local IP addresses of each
eNodeB. An eNodeB automatically obtains the IP addresses of the peer eNodeB and sets up an X2 interface to the peer
eNodeB. This document describes two X2 self-setup modes: X2 over S1 and X2 over M2000. For details about other
modes, see S1/X2/OM Channel Management Feature Parameter Description, which also includes descriptions about X2
self-setup in IPSec-enabled scenarios.
When ENodeBSharingMode.ENodeBSharingMode is set to SHARED_FREQ, the neighboring eNodeB PLMN over the
X2 interface is the primary operator PLMN of the neighboring eNodeB.
When ENodeBSharingMode.ENodeBSharingMode is set to SEPARATED_FREQ, the neighboring eNodeB PLMN over
the X2 interface is the same as the PLMN when ENodeBSharingMode.ENodeBSharingMode is set to INDEPENDENT.
8.2 X2 Self-Setup in X2 over S1 Mode
In X2 over S1 mode, the MME collects the configuration information about neighboring eNodeBs. Figure
8-2 shows the setup procedure.

eRAN
8-3
Figure 8-2 Procedure for X2 self-setup in X2 over S1 mode
The procedure is as follows:
1. When a handover is triggered, the source eNodeB checks whether an X2 interface is available
between the source eNodeB and the target eNodeB.
− If the X2 interface is available, an X2-based handover is performed.
− If the X2 interface is unavailable, an S1-based handover is performed. At the same time, the source
eNodeB triggers X2 self-setup in X2 over S1 mode. The procedure goes to step 2.
2. The source eNodeB sends an eNodeB Configuration Transfer message to the MME. The message
contains the following information:
− Source eNodeB ID, which consists of the global eNodeB ID and the selected tracking area identifier
(TAI)
− Target eNodeB ID, which consists of the global eNodeB ID and the selected TAI
− Control-plane and user-plane IP addresses of the source eNodeB

eRAN
8-4
3. The MME sends an MME Configuration Transfer message to the target eNodeB. This message
contains information about the source eNodeB. (For details about contents in the message, see
3GPP TS 36.413.)
4. After receiving the control-plane and user-plane IP addresses of the source eNodeB, the target
eNodeB uses these IP addresses and its own control-plane and user-plane IP addresses to
configure an X2eNodeB MO and sets up control-plane and user-plane bearers for the X2 interface.
Then, the target eNodeB responds to the MME with an eNodeB Configuration Transfer message,
which contains the control-plane and user-plane IP addresses of the target eNodeB.
5. The MME sends an MME Configuration Transfer message to the source eNodeB. This message
contains the control-plane and user-plane IP addresses of the target eNodeB.
6. After receiving the control-plane and user-plane IP addresses of the target eNodeB, the source
eNodeB uses these IP addresses and its own control-plane and user-plane IP addresses to
configure an X2eNodeB MO and sets up control-plane and user-plane bearers for the X2 interface.
7. When signaling exchange over the S1 interface is complete, an eNodeB sends an X2 setup request
to the peer eNodeB and the peer eNodeB responds to the request. An X2 interface is automatically
set up. Note that before receiving an X2 Setup Request message, both the source eNodeB and the
target eNodeB can send the X2 Setup Request message to and receive the X2 Setup Response
message from the peer end.
8. If a handover between the two eNodeBs is triggered after the X2 setup, the handover will be
performed through the X2 interface.
NOTE
In RAN sharing with dedicated carriers mode, control-plane and user-plane IP addresses are configured separately for
each operator, and therefore X2Interface and X2eNodeB MOs must also be separately configured for each operator.
In RAN sharing with common carriers mode, only one X2Interface MO needs to be configured, corresponding to the
primary operator. If the primary and secondary operators share user-plane IP addresses, only one X2eNodeB MO needs
to be configured. If the primary and secondary operators use different user-plane IP addresses, one X2eNodeB MO must
be configured for each operator.
8.3 X2 Self-Setup in X2 over M2000 Mode
In X2 over M2000 mode, the M2000 collects the configuration information about neighboring eNodeBs.
Figure 8-3 shows the setup procedure.

eRAN
8-5
Figure 8-3 Procedure for X2 self-setup in X2 over M2000 mode
The procedure is as follows:
1. When a handover is triggered, the source eNodeB checks whether an X2 interface is available
between the source eNodeB and the target eNodeB.
− If the X2 interface is available, an X2-based handover is performed.
− If the X2 interface is unavailable, an S1-based handover is performed. At the same time, the source
eNodeB triggers X2 self-setup in X2 over M2000 mode. The procedure goes to step 2.
2. The source eNodeB sends an X2 self-setup request to the M2000. The request message contains
the PLMN IDs and eNodeB IDs of the source and target eNodeBs.
3. After receiving the request, the M2000 searches for the configuration information (such as the X2
control-plane IP addresses and X2 user-plane IP addresses) about the source and target eNodeBs.
Based on the configuration information, the M2000 configures two X2eNodeB MOs.
4. The M2000 sends the X2eNodeB MO configurations to the source and target eNodeBs.

eRAN
8-6
5. The source and target eNodeBs set up an SCTP link between them. The control plane on the X2
interface is set up. Note that before receiving an X2 Setup Request message, both the source
eNodeB and the target eNodeB can send the X2 Setup Request message to and receive the X2
Setup Response message from the peer end.
6. After an X2-based handover is triggered, the source and target eNodeBs set up an IP path between
them. The user plane on the X2 interface is set up.
NOTE
The X2 over M2000 mode can be used only if the source and target eNodeBs are managed by the same M2000.
8.4 eNodeB Configuration Update Based on X2 Messages
If an X2 interface is configured between two eNodeBs, the eNodeB information is exchanged through
the X2 interface during an X2 setup and eNodeB configuration updates. For details on the messages
transmitted during X2 setups and eNodeB configuration updates, see section 8.3 in 3GPP TS 36.423
V10.0.0 (2010-12).
After an X2 interface is configured between two eNodeBs, the eNodeB information is updated, as
outlined in Figure 8-4.
Figure 8-4 X2 setup
1. After receiving an X2 Setup Request message from eNodeB 1, eNodeB 2 adds all cells under
eNodeB 1 to the NCL of eNodeB 2 if GlobalProcSwitch.X2BasedUptENodeBCfgSwitch is set to
ON for eNodeB 2.
2. eNodeB 2 responds with an X2 Setup Response message. After receiving this message, eNodeB 1
adds all cells under eNodeB 2 to the NCL of eNodeB 1 if
GlobalProcSwitch.X2BasedUptENodeBCfgSwitch is set to ON for eNodeB 1.
After the configuration of an eNodeB is updated, the configuration is updated in the peer eNodeB, as
outlined in Figure 8-5.
Figure 8-5 eNodeB configuration update

eRAN
8-7
1. When the local cell or neighboring cell configuration changes in eNodeB 1, eNodeB 1 sends an
eNodeB Configuration Update message to eNodeB 2.
After eNodeB 2 receives the message, it performs the following operations if
GlobalProcSwitch.X2BasedUptENodeBCfgSwitch is set to ON:
 If the NCL of eNodeB 2 does not contain the cell in the message, eNodeB 2 adds the cell to its NCL.
 If the NCL of eNodeB 2 contains the cell in the message, eNodeB 2 updates its NCL and NRTs. The updated
information includes the operating frequency, PCI, ECGI, TAC, and PLMN list.
If no active cell exists under eNodeB 1, the configuration change information cannot be sent to eNodeB 2 through X2
messages.
2. eNodeB 2 responds with an eNodeB Configuration Update Acknowledge message.
Before modifying eNodeB configuration data (such as eNodeBId, CellId, LocalCellId, CnOperator,
CnOperatorTa, CellOp, PhyCellId, or DlEarfcn) on a CME, set
GlobalProcSwitch.X2BasedUptENodeBCfgSwitch to OFF. This ensures that configuration data will
not be automatically updated based on X2 messages when configuration data is modified through the
CME, avoiding the conflict between the two data modification procedures.

eRAN
ANR Management 9 Related Features
9-1
9 Related Features
9.1 Intra-RAT ANR
9.1.1 Required Features
None
9.1.2 Mutually Exclusive Features
None
9.1.3 Affected Features
Intra-RAT ANR has an impact on LOFD-002007 PCI Collision Detection & Self-Optimization.
When neighboring cell information changes because of intra-RAT ANR, PCI conflict detection is
triggered.
9.2 Inter-RAT ANR
None
None
None
9.3 X2 Self-Setup
None
None
None

eRAN
ANR Management 10 Impact on the Network
10-1
10 Impact on the Network
10.1 Intra-RAT ANR
10.1.1 Impact on System Capacity
N/A
10.1.2 Impact on Network Performance
Intra-RAT event-triggered ANR introduces extra delays in handovers of the UEs that meet the handover
conditions but are still performing ANR periodic measurements. In addition, it affects the UE throughput
because UEs cannot be scheduled when they are reading the CGI and other information about an
unknown cell during DRX periods.
Intra-RAT fast ANR has the following influence on network performance:
 The UE throughput is unaffected during the process that the UE periodically measures intra-frequency
neighboring cells and reports the PCI of the neighboring cell with the highest signal quality.
 The UE throughput drops when:
− The UE reads the CGI and other information about an unknown cell during DRX periods. This drop
occurs because the UE cannot be scheduled during DRX periods.
− The UE performs gap-assisted measurements on inter-frequency or inter-RAT neighboring cells.
 Generally, the influence that fast ANR exerts over network performance is controllable and acceptable,
because of the upper limits on the number of UEs involved in fast ANR per cell and on the number of
periodic measurement reports by a UE within each period.
Intra-RAT ANR optimizes and manages intra-RAT neighbor relations, thereby reducing service drops
and handover failures caused by inappropriate neighbor relations. The gain that ANR brings to the
handover success rate and service drop rate cannot be provided here because many factors, such as
the number and distribution of ANR-capable UEs, will affect the handover success rate and service drop
rate.
The handover success rate and service drop rate are reflected by the following counters:
 Intra-frequency Handover Out Success Rate
 Inter-frequency Handover Out Success Rate
 Service Drop Rate
Service Drop Rate = (L.E-RAB.AbnormRel/L.E-RAB.NormRel + L.E-RAB.AbnormRel) x 100%
Where, L.E-RAB.AbnormRel provides the number of abnormally released E-RABs and
L.E-RAB.NormRel provides the number of normally released E-RABs.
10.2 Inter-RAT ANR
10.2.1 Impact on System Capacity
N/A
10.2.2 Impact on Network Performance
Inter-RAT ANR has basically the same influence on network performance as intra-RAT ANR does. The
difference is that inter-RAT ANR has an impact on the following KPIs:

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