SON,self optimized network

1. Distribution
EnglishED01
Jae ho, Lee
Customer Training Center

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Contents
SON general information and structure
Self-Establishment
Self-Optimization

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SON function and Scope
3GPP SON specification
Samsung LTE SON Structure

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SON function and Scope
SON = (Self Planning) + Self Establishment
+ Self Optimization + (Self Healing)
LTE SON Server
eNB
More Efficient Operation
of Telecommunication System
OPEX Reduction &
Performance Enhancement

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SON Technology Scope
Self-Planning
- Automatically derive
few Radio parameters
for eNBs which will be
established.
- Reduce amount of
manual pre-planning
Activities
- Reduce self-
configuration errors
Network Lifecycle
Planning Deployment Optimization Maintenance
Self-Configuring
- Plug-n-Play Hardware
- Self-Configuration Radio
Parameters
. Initial PCI,
. Initial NR,
. Initial PRACH configuration
- Automatic IP Acquisition
- Automatic Neighbor Lists
- Automatic Connectivity
establishment
- Self-test and S/W
download
Self-Optimizing
- Automatic Neighbor
Relation Optimization
- Mobility Robustness
Optimization
- Mobility Based Load
balancing
- RACH optimization
- Energy Cost
Optimization
- Coverage & Capacity
Optimization
Self-Healing
- Auto Cell Outage
Detection
- Auto Cell Outage
Compensation

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3GPP SON Specification
Function Contents Spec. Related specification
Self- Establishment
(Self-Configuration)
Automation for eNB installation and initial radio parameter
configuration
(Initial PCI, Initial Neighbor configuration, Initial PRACH info.)
Rel-8
32.501, 32.502, 32.531, 32.532,
32.533, 32.537, 36.300
Self-
Optimiza
tion
Automatic PCI
Configuration
PCI is automatically allocated and re-allocation for PCI
confliction.
Rel-8 36.902, 36.300, 36.423
Automatic Neighbor
Relation
Detect Neighbor Cell automatically and Neighbor Cell List
configuration(optimization)
Rel-8
32.511, 32.761, 32,762, 32.763,
32.765
36.300, 36.331, 36.413, 36.423
Mobility Robustness
Optimization
Detect the problem of Handover automatically and HO
parameter configuration
Rel-9
32.816, 32.521, 32.522, 32.523,
36.902, 36.300, 36.314, 36.423
Mobility Load Balancing
Opt.
cell reselection /HO parameter optimization for cell traffic
load balancing
Rel-9
32.816, 32.521, 32.522, 32.523
36.902, 36.300, 36.314, 36.423
RACH Optimization
RACH parameter optimization and minimize interference for
Access delay and RACH
Rel-9
32.521, 32.522, 32.523,
36.902, 36.300, 36.423
Inter Cell Interference
Coordination
Improvement for edge performance with minimized
neighbor-cell interference
Rel-8
36.213, 36.214, 36.423
32.521, 32.522, 32.523
Coverage & Capacity
Opt.
Analyzing the problem of Coverage and Capacity, Cell
Coverage and Capacity optimization
Rel-10
expected
32.816, 32.521, 32.522, 32.523,
36.902, 36.300, 36.423
Self-
Healing
Alarm monitoring
Real-time monitoring of alarms.
Collection & Analysis for correlated information
Triggering of self-healing
Rel-10
32.541, 32.542, 32.543, 32.823
COD: cell outage detection
COR: cell outage recovery
COC: cell outage compensation
Self-recovery of NE S/W Recover NW S/W to initial states and recent backup states.
Self-healing of board
fault
Detect Board fault and decrease and delete automatically
the user impact.
Self-healing of cell
outage
When it happen Cell outage, it stats automatic
compensation for network problem (COD, COR, COC)
Minimization of Drive-Tests
Define the kind of UE measurement, collection method,
transmission structure for replacing drive-test.
Rel-10
TR 36,805
TS 37.320
Energy Saving Management
Down energy cost for providing cell capacity as traffic
requests,
Rel-10
TR 32.826 (new),
TR 36.902
TS 32.551

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SON Structure (1) : Feature Overview
MSS*
LSM
(EMS)
eNB
UE
Provision Deployment Operation & Maintenance
• eNB Provisioning
- eNB type, ID, pkg, etc.
• eNB Establishment
1. Power On Self Test
2. IP Acquisition (DHCP)
- eNB ID, eNB IP, LSM IP
3. eNB Registration
4. SW Download & Check
5. Configuration Download
- Initial Radio Parameters
6. S1/X2 Setup (SCTP)
7. RRH Configuration
8. In-service
• Self-Configuration
- Initial PCI, PRACH, NRT for eNB/Cell
•eNB Registration
• KPI/Trace Monitoring
• PCI/PRACH Collision Resolution
• Self-Optimization
• Measurements & Reports
- Serving/Neighbor Signal Quality
- Handover / RACH events
Event-based
- ANR (Add)
- PCI (Contention)
- RACH (Collision)
HO Statistics-based
- ANR (Ranking)
- MRO
- RACH (# of preambles)
RACH Statistics-based
- RACH (time, power)
Traffic Statistics-based
- Load Balancing
* MSS shall be provided by operator requirement.
• Interface with OSS (Operation Support System)
• SON Data Interworking for Inter-LSM
- PCI, PRACH, NRT for eNB/Cell groups
•Self-Configuration (When it use MSS)
- Initial PCI, PRACH, NRT for eNB/Cell
MSS: Master SON Server

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SON Structure(2)
MSS
LSM
(EMS)
eNB
SONF OAM CallP
Neighbor eNB
CallP
X2 SETUP REQ/RSP
ENB CONF UPDATE
SONF
SONF
SON interface
- Inter Vendor,
- Inter LSM,
- Inter RAT
Operator Specific SON interface
SON Interface
- Self-Configuration
- Self-Optimization
Configuration
Update
Operator operation server, Integrated DB,
Optimized Server

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Master SON Server Fucntion
Self Configuration
Initial PCI
Initial NR
Initial PRACH information
Support SC and SO function: LSM-LSM or integrity DB Coordination.
Initial PCI/RACH/NR information configuration precedure
When it deletes Cell/eNB
PCI Reconfiguration procedure
RSI Reconfiguration procedure
P5: After New PCI detection, ECGI obtaining (LSM based)
P6: After New ECGI obtaining, NR info. Configuration procedure(UE based)

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SON Operation per function
SON Operation Mode: Off / Manual Apply / Automatic Apply
Function SON Operation
Off Execute the collection of requested input data, there is no parameter-change.
Manual Apply After Operator의 confirm procedure, Parameter-change, Controlled Operation (open loop)in
specification
Automatic
Apply
Automatic parameter change, autonomous operation (closed loop) in specification

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SON Operation per function
SON’s Operation Mode per function
SON
function
Off/Manual Apply/Automatic Apply operation
PCI
• Automatic apply : Initial PCI configuration(auto), X2 monitoring, Detect PCI collision/confusion, PCI re-configuration
• Manual apply : Initial PCI Configuration(auto), X2 monitoring, Detect PCI collision/confusion, Request to operators for PCI re-
configuration
• Off : X2 monitoring
ANR
• Automatic apply: If New PCI appear, add NR automatically, X2 monitoring, delete NR automatically with detecting neighbor
cell and NR-ranking
• Manual apply: When it deletes Neighbors based Ranking/X2, Operator의 Request Confirm (Response) of operator
• Off: X2 monitoring, NR-ranking starts with collecting Handover statistic data, no NR change
RACH
• Automatic apply: Change Parameter automatically
• Manual apply: Operator-confirm procedure is first and change parameter
• Off: X2 monitoring, needed input data collection, No parameter change

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SE Procedure
SE Provisioning
SE Operation
HW Test (Power on Self Test)
Get eNB ID, eNB IP and LSM (EMS) IP automatically
S/W, Loading configuration info. and Validation check
S1/X2 auto-configuration
RRH Configuration
Report Self-Test result

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SE Provisioning environment/Configuration
Input system basic information
eNB Type
eNB ID
eNB serial number (In case of using DHCP key)
MME IP address
SC Mode configuration and initial parameter auto-creation
Initial Physical Cell Id
Initial neighbor information
Root Sequence Index

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SC item configuration (On/Off)
SC Result (On) [Off :need manual input]
Example (other Korea operator)
Select automation
PCI auto allocation
Initial neighbor auto-configuration
RACH optimization
Information
Add system
Detail information
Detail information
Cell Management
Information
Auto-allocation/initial neighbor/RACH opti.
State

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eNB ID, eNB IP, LSM IP Manual input
The procedure of manual input
Configuration for eNB environment information
– Mandatory configuration
– BOOTSTATICIP : eNB의 IP address (Information related DHCP)
– BOOTSTATICMASK : BOOTSTATICIP net-mask (Information related DHCP)
– BOOTSTATICGW : BOOTSTATICIP의 GW address (Information related DHCP)
– RS_IP : LSM의 IP
– NE_ID : eNB의 ID
– serverip : LSM의 IP address
– ipaddr : eNB의 IP adress, same configuration with BOOTSTATICIP
– example
eNB Reboot starts
> Retrieve command : getenv [-a] <env_name>
> Configuration command : setenv –p <env_name> <env_value>
root@UAMA:/root> setenv -p NE_ID 9
config string
setenv complete
root@UAMA:/root> getenv NE_ID
NE_ID=9
> reboot

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Retrieve configuration for S1/X2
S1 auto-configuration and retrieve the status
The function for retrieving S1 status
X2 auto-configuration and retrieve command
The function fort retrieving X2 status
Retrieve command
: RTRV-S1-STS;
Retrieve command
: RTRV-X2-STS;

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Self Optimization
Automatic Neighbor Relation ( ANR)
Energy Cost Optimization (ECO)
Inter Cell Interference Coordination (ICIC)
Physical Cell ID Auto Configuration (PCI)
Mobility Robustness Optimization (MRO)
RACH Optimization (RO)

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ANR Definition
ANR Operation
NRT Structure

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ANR Definition
Auto management for NRT (Neighbor Relation Table) on
Handover and Interference Management
Self Establishment step: Under Installation, Initial NRT auto-configuration using
operating eNB information
Self Optimization step: Under operation, Neighbor Add/Ranking/Remove /HO
Black list/Recover function of NRT

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ANR Operation
NRT Add: Add NRT and HO attempt
UE UE
eNB
(Serving Cell)
New eNB
(Target Cell)
UE
⑩ Handover
(X2 or S1)
① UE measurement
⑨ X2 set-up
⑥ NRT Udate
(Add a new cell)
LSM
iInitial NRT
⑤ report CGI
⑧ IP address acquisition
of the new eNB
MME
③ Report CGI Request
⑦ NR report
④ Read CGI② Measurement report (New PCI)
③ Report CGI Request
⑤ Report CGI

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ANR Operation
NRT Add: Field Test result in Korea
3 times x (Pingpong included) 10 HOs/count = 30 HOs are success
수원플라자
a
b
g
동수원
a
b
매교
a
ANR 동작 지역들

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ANR Operation
Neighbor Ranking
Initial NRT: Ranking based on the length between BSs
Operating NRT: Ranking based on Handover Attempts, Handover Success
Handover Black List
Definition: ‘No HO’ field is On and no handover with Neighbors
No Relation ‘No HO’ unchecked ‘No HO’ checked
NR Add Operation
1. NR add by operator
2. NR add by initial-NRT
3. NR add by UE-MR
NR Remove Operation
1. NR remove by operator
2. NR remove by X2
‘No HO’ attribute ON
1. Manual input by operator
2. NRT Full & NR-ranking
3. HO KPI
4. HO-to-wrong cell
‘No HO’ attribute OFF
1. Manual Input by operator
2. HO-to-black cell
NR Remove Operation
1. NR remove by operator
2. NR remove by X2

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NRT Construction
NRT contains1)
Target Cell Identifier (TCI)
E-UTAN Cell Global Identifier (ECGI)
Physical Cell Identifier (PCI)
No Remove: If checked, the eNB
shall not remove the Neighbour
cell Relation from the NRT.
No HO: If checked, the Neighbour
cell Relation shall not be used by
the eNB for handover reasons.
No X2: If checked, the Neighbour
Relation shall not use an X2
interface in order to initiate
procedures towards the eNB
parenting the target cell.
1) 3GPP TS 36.300 Section 22.3.2a
Neighbour
Detection
Function
Internal
Iinformation
RRC
Mrmnt
reports
Mrmnt
requests
Add/UpdateNeighborRelations
NRreport
ANR function
eNB
O&M
NRadd
NRT
Managemnt
Function
Neighbour
Removal
Function
NRremove
NRupdate
Neighbor Relation Table
1
2
TCI
3
No
Remove
TCI#1
TCI#1
No HO No X2
O&M controlled
Neighbour Relation Attributes
Neighbour Relation
NR
TCl#1

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ICIC Definition
ICIC Operation

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ICIC Definition
Improvement user’s throughput decreasing cell interference using
radio resource
Self Establishment step: not applicable
Self Optimization step: In operating, communicate interference information
between cells, control interference to allocate limited tx power(radio resource) for
users.

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ICIC Operation
Interference
① X2 Load Information
(I’m suffering from high interference)
② RSRP measurement
(I’m near the neighbor)
③ Tx power optimization
(Reduce Tx power!)

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PCI Auto-configuration Definition
PCI Auto-configuration Operation

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PCI Auto-configuration Definition
PCI (Physical Cell Identifier): Collision-free, Confusion-free, Unique
ID for identify the area for minimize interference between RSs
Collision-free: Two neighboring cells should not use the same PCI.
Confusion-free: A cell should not have two neighbors with the same PCI
Minimize interference among RS (cell-specific Reference Signal)
Self Establishment step: under installation, Initial PCI allocation is executed using
operating eNB information
Self Optimization step: in operating, Detect PCI collision/confusion and re-
allocation with exchanging message using X2 interfaces

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PCI Auto-configuration Operation
PCI Charactersitics1)
PCI (Ncell
ID)는 PCI group (N(1)
ID) 과 PCI within PCI group (N(2)
ID)
– 168 PCI groups * 3 PCIs/group = 504 PCIs
–
Using the area needed cell specific randomness like DL/UL physical channel
scrambling, resource element mapping, cyclic shift, hopping and reference signal
generation.
Needs optimization for re-using PCI
In Seoul 2,065 sites
– Main system 1,403 sites
– In-building 662 sites
1) 3GPP TR 36.211
(2)
ID
(1)
ID
cell
ID 3 NNN 
650m
650m

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RO Definition
RACH Parameters
RO Operation

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RO Definition
Optimized allocation for RACH resource in Cell
Self Establishment step: under installation, executes Initial root sequence index,
PRACH configuration index, PRACH configuration offset allocation using operating
eNB information
Self Optimization step: in operating,
– Optimize the number of Dedicated Preamble using Handover statistic data.
– PRACH power/opportunity optimization based on UE information statistic data.
– Re-allocation after detecting root sequence index collision with exchanging X2 interface
messages

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RACH Parameters
RACH Procedure1)
Contention-based Preamble vs. Dedicated Preamble: Use 64 preambles in each
cell.
Preamble Initial Received Target Power, Power Ramping Step
PRACH Configuration Index
…
1) 3GPP TR 36.902, Section 4.7.4

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RO Operation (1/3)
Initial PRACH parameter auto-configuration1)
1) Initial NRT based on distance
2) Calculates average distance(D) between neighbor cell on Initial NRT
3) Calculation RSI (Root Sequence Index) Reuse Black List
– RSI Reuse Black List standard distance = max{ R, n*D}
– R: standard distance configured by operators, 0~100 Km, default = 0 Km
– n: standard configured by operators, 1~10, default = 2
4) Allocates2) RSI except RCI Reuse Black List
– If there is no available RSI, allocate max value of Reuse Distance
5) Allocates PRACH Configuration Index per sector
– PRACH Configuration Index: (alpha, beta, gamma) = (3, 4, 5)
– Over 4 sectors, allocates additional Root Sequence Index
1) It’s depend on operators
2) High Speed Flag = False (default), Zero Correlated Zone Configuration = 12 (default)

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RO Operation (2/3)
Collection PRACH Data
Data collection based on X2 Handover Request/Response messages
– Dedicated Preamble Assignment Success/Fail
Data collection based on UE Information Request/Response messages
– Number of Preambles Sent
– Contention Detected

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RO Operation (3/3)
PRACH Data Analysis
Statistic analysis
– Threshold value is configured by operators
RACH Parameter Change
RACH Resource optimization considering RACH load, Handover, Random Access
Delay performance in operating.
– Dedicated Preamble allocation success-ratio
 Number of RA Preambles Optimization
– UE Information (Preamble Re-transmission counts + Confliction counts)
 PRACH Configuration Index, Power Ramping Step, Preamble Initial Received Target Power
Optimization
1
0.1
0 1 2 3 4 … … i i+1 100 [%]
Dedicated_fail_ratio
tbd
CDF/PDF
Th_de_upper = tbd
Th_de_increase = tbd %
YDed(k)
...