LTE Feature Performance

http://www.linkedin.com/pub/ray-khastur/36/965/b7a

LTE Feature Performance

4G LTE Feature Performance| Page 2

Beam Forming


Beamforming Increase Capacity

2R

8T Single &Dual flow adaptive BF

UE

1

2

3

4

S UES

Single-flow BF 11

21

31

41

UE1222

32

42

S2

S1

S1

S2

Single user dual-flow BF

4T Single-flow BF

4T Dual-flow BF

Cell A

Cell B

Cell C

DL 4*2 BF: Single &Dual flow adaptive

DL 2*2 MIMO

15% Increase

Average Throughput Edge-User Throughput

25% Increase

* Based on Huawei system simulation

15% Increase

28% Increase

DL 8*2 BF: Single &Dual flow adaptive

Thro

ugh

pu

t (M

bp

s)

BF with better SINR Benefits

BF significantly improve downlink system throughput and coverage performance and also provide good user experience by offering higher data rates.


MIMO & Beamforming Adaptation

Adaptive MIMO

DL Scheme

Open Loop Utilize CSI

SFBC/TM2 SM/TM3 Single layer

/TM7,TM8

Dual layer,MU-BF

/TM8

Low speed move UE High speed move UE

Cell edge Cell center Cell edge Cell center

MIMO mode and Beamforming are adaptive

according to channel condition and users velocity

Scenario of low speed and low channel correlation

Scenario of high speed


IRC


IRC to reduce UL interference

Gain of 7dB at 10-1 FER in interference limited environment

MMSE: Minimum Mean Square Error IRC: Interference Rejection Combination ICE: Ideal Channel Estimate RCE: Real Channel Estimate MRC: Maximum Ratio Combination IRC: Interference Rejection Combination

Signal Interference

Cell1

Cell2

Cell3

Noise Evaluated antenna 1

antenna 2 Noise

Evaluated

combining

+

=

=

-

-

When Uplink inter-cell interference arise

IRC uses the spatial characteristics of

inter-cell interference.

Consider interference correlation.

Evaluate the power of interference and

remove it.

Enhance Coverage and capacity in interference

limited scenario.


Comparison Static ICIC and Dynamic ICIC


Inter-Cell Interference Coordination

1

2

3

6

5

7

4 1

2

3

6

5

7

4

Frequency

Cell 1 Power

Frequency

Cell 2,4,6 Power

Frequency

Cell 3,5,7 Power

DL Load DL ICIC Gain (dB) UL ICIC Gain (dB)

100% 2 0.3

70% 1.5 0.2

50% 0.5 0.1

30% 0 0

0% 0 0

Increase the coverage Increase cell edge data rate Link Cell edge 5% user

DL ICIC OFF Benchmark

DL ICIC ON 36.2%

UL ICIC OFF Benchmark

UL ICIC ON 13.9%

ICIC reduces the inter-cell interference, improves cell edge users throughput


Content

1 Overview of SFR & ICIC Feature on TD-LTE

2 Coverage Prediction of TD-LTE with SFR

3 Summary

Adaptive ICIC: Improve 30% Cell Edge Throughput

Adaptive ICIC switch on / off

Support cell edge frequency

reuse (1, 1/3, 1/6).

Frequency: reuse=1 Frequency: reuse=3

Cell Edge

Interference

High

Cell edge interference lead

to low throughput

Unique cell edge frequency reuse 6 in telecom

industry

Adaptive ICIC:

Cell Edge

Throughput

Low Cell Edge Interference

Low

Cell Edge

Throughput

30% improved

eCoordinator


Content


2 Coverage Prediction of TD-LTE with ICIC

3 Summary

SINR Coverage with Adaptive ICIC

SINR Coverage without ICIC

Comparison of Implementation ICIC - SINR

In TD-LTE configuration 1x3x1 all sector using same resource carrier, the disadvantage of using single frequency is in the cell edge, end user equipment will deteriorate of signal quality due to UE receive same frequency that will impact as interferer. In this simulation UE using Smartphone in the outdoor case.

Adaptive ICIC is the most powerful feature to minimize interference in the cell edge, this type of SFR will divided BW in 6 style of cell edge. In the center of cell SINR size better than using static ICIC.

SINR Coverage with Static ICIC

SINR Coverage without ICIC

In TD-LTE configuration 1x3x1 all sector using same resource carrier, the disadvantage of using single frequency is in the cell edge, end user equipment will deteriorate of signal quality due to UE receive same frequency that will impact as interferer. In this simulation UE using Smartphone in the outdoor case.

By using SFR (Soft Frequency Reuse), same like FFR (Fractional Frequency Reuse) in WiMAX technology. The Bandwidth divided into 3 style of edge, which 1/3 BW will be used in cell edge then 2/3 BW will be used in the center of cell. This method to minimize interference and improve the cell edge throughput.

Comparison of Implementation ICIC - SINR

Without ICIC With Static ICIC

With Adaptive ICIC

Comparison of Implementation ICIC - SINR (Animation)

Comparison of Implementation ICIC SINR Statistic

There is SINR improvement with using ICIC feature, Adaptive ICIC show the best improvement than Static ICIC

Radio Bearer Coverage with Static ICIC

Radio Bearer Coverage without ICIC

Comparison of Implementation ICIC Radio Bearer

TD-LTE modulation coding scheme without implementing ICIC is much degraded in the cell edge, especially in the inner city. End User in the cell edge will get QPSK as the highest MSC that serving their UE.

After implementing AFP function in U-Net for static ICIC we get better improvement in the cell edge area. Bur on the center of coverage cell radius of MCS 64 QAM will be reduce.

Radio Bearer Coverage with Adaptive ICIC

Radio Bearer Coverage without ICIC

Comparison of Implementation ICIC Radio Bearer

TD-LTE modulation coding scheme without implementing ICIC is much degraded in the cell edge, especially in the inner city. End User in the cell edge will get QPSK as the highest MSC that serving their UE.

After conduct AFP with adaptive ICIC, the cell edge is better than static ICIC. And the cell radius of MCS 64 QAM is more longer than static ICIC.

Comparison of Implementation ICIC Radio Bearer (Animation)

Without ICIC With Static ICIC With Adaptive ICIC

DL Throughput Coverage with Static ICIC

DL Throughput Coverage without ICIC

Comparison of Implementation ICIC DL Throughput

In TD-LTE without activating ICIC, we can see much of area in the inner city with low DL Throughout due to impact of interference from same frequency that receive by UE.

After implementing static ICIC, there are much improvement for DL Throughput than before. End user experience will be increase while interference impact decrease.

DL Throughput Coverage with Adaptive ICIC

DL Throughput Coverage without ICIC

Comparison of Implementation ICIC DL Throughput

In TD-LTE without activating ICIC, we can see much of area in the inner city with low DL Throughout due to impact of interference from same frequency that receive by UE.

After implementing adaptive ICIC, cell edge DL Throughput are better than static ICIC, really recommend to using this feature to manipulate lack of customer BW resource.

Without ICIC

Comparison of Implementation ICIC DL Throughput (Animation)

With Static ICIC With Adaptive ICIC

Comparison of Implementation ICIC DL Throughput Statistic

This graphic show the cumulative of DL Throughput from all coverage, even the cumulative of TD-LTE without ICIC is better, but the this is just focus on center of center of cell coverage. The cell edge throughput is better after implementing of ICIC


Content


2 Coverage Prediction of TD-LTE with SFR

3 Summary


Summary

Frequency: reuse=6

eCoordinator

Adaptive frequency reuse pattern selection: The system automatically

selects an appropriate edge frequency allocation pattern for each cell.

The patterns for allocating cell edge frequencies are as follows:

Reuse1, Reuse3, and Resue6. These patterns can be flexibly used in

different scenarios. For example, reuse1 is used in the low interference

scenario, reuse3 is used in medium interference scenario and reuse6

is used in the high interference with mass neighbor cells scenario.

Static ICICcell center use 2/3 bandcell edge use 1/3 bandso, in cell edge, frequency reuse 3, different cell edge use different frequency. Tx power in cell center lower than cell edge Tx power to control interference.


Self Optimization Network : ANR


ANR Classification

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).


ANR Feature Benefit and influence Benefit

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.

Event ANR

Find the missing neighbor cells when handover measurement is reported, handover success rate and

call drop rate can be improved.

Fast ANR

Choose some UE to measure neighbor cells and report periodically, the neighbor cell relations can be

convergent more faster.


ANR Feature Benefit and influence Influence

Event ANR

CGI report process will introduces extra delays in handovers of the UEs that meet the handover

conditions.

Fast ANR

In fast ANR processes, UE will report PCI periodically and read CGI when the neighbor cell is unknown.

In intra-frequency scene, periodical PCI reporting does not impact system performance, whereas CGI

reading interrupts UE services.

In inter-frequency and inter-RAT scene, periodical PCI reporting impacts UE throughput, and CGI

reading interrupts UE services.


Relation between ANR and others

Intra-RAT ANR

Intra-RAT ANR needs UE to support Long DRX cycle and ANR-related measurement. If

ANR measurements need to be performed, a temporary dedicated DRX cycle needs

to be configured for the UE. During this cycle, the UE obtains the CGIs of neighboring

cells in dormancy periods.

Intra-RAT ANR has an impact on Feature PCI Collision Detection & Self-Optimization.

When neighboring cell information changes because of intra-RAT ANR, PCI conflict

detection is triggered.

Inter-RAT ANR

Inter-RAT ANR needs UE to support Long DRX cycle and ANR-related measurement.

If ANR measurements need to be performed, a temporary dedicated DRX cycle

needs to be configured for the UE.

Relation between ANR and others


Intra-RAT Event ANR - Missing Neighbor Detection

By UE Measurement

1. The source eNodeB delivers the intra/inter-frequency measurement configuration to the UE, instructing the UE to measure neighboring cells that work on the frequencies specified in the measurement configuration.

2. The UE detects that the PCI of cell B meets the measurement requirements, and reports the PCI to the source 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).

5. The UE reports the obtained parameter values to the source eNodeB.


Intra-RAT Event ANR - Missing Neighbor Detection

Source Cell

(Cell A)

Target Cell

(Cell B)

M2000

2.Handover response

1.Handover request

3.Report cell A ECGI

Information query

4.Send info to cell B

By UE UE History Information 1. The source eNodeB sends a Handover Request

message to the target eNodeB including UE

history information.

2. The target eNodeB obtains the UE history

information from the message. If the target

eNodeB detects that the ECGI of the last visited

cell (that is, cell A, the source cell) does not exist

in the NCL of the target cell (cell B), cell A is

considered as a new neighboring cell of cell B.

3. The target eNodeB reports the ECGI of cell A to

the M2000.

4. 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.

5. The target eNodeB adds cell A to the intra-RAT

NCL of cell B.


Inter-RAT Event ANR

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.

2. The UE detects that cell B meets the measurement requirements and reports its scrambling code to cell A. 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).

If cell B is a CDMA2000 cell, only the CGI is to be read. 4. The source eNodeB schedules appropriate measurement

gaps 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.


Intra & Inter-RAT Fast ANR

In order to reduces the impact of event-triggered UE measurements on handover performance, system supports period measurement.

Period measurement report


Intra & Inter-RAT Fast ANR

Periodic UE measurements have a negative impact on the uplink throughput of the network. Therefore, fast ANR restricts the number of concurrent UEs involved in periodic measurements by several mechanisms.

When current UE number involved in fast ANR achieve the threshold, eNodeB stop selecting new UE for fast ANR When the specific UE measurements achieve the threshold, the UE stop fast ANR report

When the total Ue number involved in fast ANR achieve the threshold in the certain period, the eNodeB will get into the state of monitoring or start a new FastAnr Period .


Neighbor Relations MaintenanceNRT/NCL Maintenance

Added to NRT / NCL

Period calculation

Adjust the list of NRT

Result analysis

Removed from NRT / NCL

Kept in NRT / NCL


Self Optimization Network : CSFB


CSFB: Architecture and functionalities

S1-MME

S1-U

S11

E-UTRAN

MME

S-GW

S5

SGSN

HSS/HLR

S6a

S4

S3

S12

Iu-ps

Gb

PDN-GW

SGi

S7

MSC/VLR

A

Iu-cs

Gr

SGs

G/U/L handset

Multi-mode G/U/L

CSFB capable

Support of procedures:

Combined EPS/IMSI

Attach, Update, Detach.

Deriving a VLR number and LAI

from the TAI of the current cell, or

using a default VLR number and LAI.

Maintaining SGs association with

MSC/VLR for EPS/IMSI Attached UE

Triggering paging to eNodeB (when

MSC-S pages the UE)

Initiating IMSI Detach at EPS

Detach

GERAN

UTRAN

Need to be R8 ready

Maintaining SGs

association with MME

Forwarding paging request for CS

domain to the UE.

Directing the UE to the target CS

capable cell. (PS HO/redirection

with or without SIBs).

C/D

PCRF

Rx

Internet / intranet /

Operators & 3rd

Party Applications

Gs

for the mobility

management and

paging procedures

between EPS and

CS domain.


CSFB: Mobile Originating call

Page 38

CSFB MO procedure:

A: Voice service request is activated from UE;

B: MME indicates UE fall back to GERAN/UTRAN for voice service via eNodeB, UE sends service request to GERAN/UTRAN; in the mean time,

MME informs GSM/UMTS CS Core to prepare resource;

C: When resource in GSM/UMTS network is allocated, UE falls back to GERAN/UTRAN for voice service; And then UE will initiate the CS voice

call, MCS processes the UEs calling request and sends IAM(Initial Address Message) to CS core.

Phase Flows

A 1.Ext Service Request (CSFB indicator)

B

2.S1 AP Message (CSFB indicator)

3.Optional measurement

4.PS HO or PS redirection

5.eNodeB direct the UE to G/U

C 6. Resource located, UE initiate CS call

7. MSC processes UEs calling(IAM)

NodeB RNC

eNodeB SAE-GW

MSC-VLR

SGs

HSS/HLR

MME

SGSN

1

5

2

3

4

6

UMTS

LTE

1

4

7

Inte

r-syste

m c

han

ge


CSFB: Mobile Terminating call

3

NodeB RNC

eNodeB SAE-GW

UMTS

LTE

MSC-VLR

SGs

2

HSS/HLR

Inte

r-syste

m c

han

ge

9

MME

1

SGSN

5 7

2 3

4 6

Phase Flows

A 1.IAM: Initial Address Message

B

2.Paging Request (Domain indicator: CS)

3.Ext Service Request (CSFB indicator)

4.S1AP Message (CSFB indicator)

5.Measurement

6.PS HO or PS Redirection

7.eNodeB direct the UE to G/U

8.Paging Response

C 9.Voice Call establishment

CSFB MT procedure:

A: GSM/UMTS MSC initiates CS paging to the called party (LTE UE), voice service is requested by LTE UE;

B: MME indicates UE fall back to GERAN/UTRAN for voice service via eNodeB, UE sends service request toGERAN/UTRAN; in the mean time,

MME informs GSM/UMTS CS Core to prepare resource;

C: When resource in GSM/UMTS network is allocated, UE falls back to GERAN/UTRAN for voice service;


CSFB to UMTS (PS HO)

MMERNCeNodeBUE MSC SGSN

Handover

Command

1. Extended Service Request

(containing a CS Fallback Indicator)

Handover Command

S1-AP Response Message

3. Optional measurement report

4. PS handover preparation phase

5.CS call establishment procedure with LAU or combined RAU/LAU

6.PS handover execution phase

2. S1-AP Message



3. S1-AP message with CS Fallback indicator

2.Extended Service Request


Service

Request

S-GW

P-GW

Paging

1.Paging Request

4. Subsequent procedure similar to that in a mobile-originated case, with the CS

call establishment procedure replaced with a Paging Response message

MO call MT call


CSFB to UMTS (PS RRC Redirection w/o RIM)

MO call (R8: without RIM)


2.S1-AP Message with CS Fallback Indicator



S1-AP Reponse Message

3.Optional measurement report

5. LAU, combined RAU/LAU, or RAU and LAU

6.CS call establishment procedure

S1 UE context release

4. RRC Connection Release with UTRAN frequency


2.S1-AP Message with CS Fallback Indicator





5. LAU, combined RAU/LAU, or RAU and LAU



4. RRC Connection Release with UTRAN

frequency\cell id\cell System information

MO call (R9: with RIM)

*MT calls procedure is same.

PS Suspend PS Suspend


CSFB to GERAN (PS HO)

MO call MT call MMEBSCeNodeBUE MSC SGSN

Handover

Command

1. Extended Service Request


Handover Command


3. Optional measurement report

4a. PS handover preparation phase

4b.Suspend

5.CS call establishment procedure with LAU or combined RAU/LAU

6.PS handover execution phase

S-GW

P-GW

Update

Bearers

2. S1-AP Message



3. S1-AP message with CS Fallback indicator



Service

Request

S-GW

P-GW

Paging

1.Paging Request

4. Subsequent procedure similar to that in a mobile-originated case, with the CS

call establishment procedure replaced with a Paging Response message

BSC

In case GERAN or UE cant support DTM (Dual transfer Mode) the PS service will be suspended


CSFB to GERAN (PS RRC Redirection w/o RIM)

MMEBSCeNodeBUE MSC SGSN

2.S1-AP Message

(containing a CS Fallback

Indicator)





6.Suspend

5.LAU, combined RAU/LAU, or RAU and LAU



4. RRC Connection Release with GERAN frequency group


2.S1-AP Message






6.Suspend




4. RRC Connection Release with GERAN frequency

group\Cell id\Cell system information

MO call (R8: without RIM) MO call (R9: with RIM)


CSFB to GERAN (CCO w/o RIM)

MO call (w/o RIM)


4. MobilityFromEUTRACommand

(CCO optionally with NACC)

2.S1-AP Message






7.Suspend



5. S1 UE context release

In case GERAN or UE cant support DTM (Dual transfer Mode) the PS service will be suspended


CSFB to UTRAN: Three mechanisms

R8 PS Handover: base on the

inter-RAT PS handover procedures

R8 PS redirection: RRC release with

redirectedCarrierInfoIE to UE

R9 PS redirection: RRC release with a

carrier frequency and UTRAN cells SIBs

acquired by RIM procedures before CSFB.


CSFB to GERAN: Four mechanisms

R8 PS Handover: base on the

inter-RAT PS handover procedures

R8 PS redirection: RRC release with

redirectedCarrierInfoIE to UE

R9 PS redirection: RRC release with a

carrier frequency list and cells SIBs

acquired by RIM procedures before CSFB.

R8 CCO with NACC: HandoverCommand

With target cell and SI

LTE Feature Performance

Engineering

Transcript of LTE Feature Performance