3GPP2 A30-20111205-xxx3GPP2 A30-20111205-xxx

TITLE: TITLE: Simulation Results for HRPD SCML with feedback sharingSOURCESOURCE

Satish Kanugovi, Alcatel-Lucent, satish.k@alcatel-lucent.com

Mike Dolan, Alcatel-Lucent, mike.dolan@alcatel-lucent.com

Sendil Kumar, RITCOE, ssk@tcoe.iitm.ac.in

Yonggang Fang, ZTE Corp., yfang@zteusa.com

Xiaowu Zhao, ZTE Corp., zhao.xiaowu@zte.com.cn

ABSTRACT: ABSTRACT: This contribution provides a set of results for HRPD This contribution provides a set of results for HRPD simulations with feedback sharingsimulations with feedback sharing

RECOMMENDATION : RECOMMENDATION : Discuss and adopt in principle.Discuss and adopt in principle.© 2011 © 2011 The contributors grants a free, irrevocable license to 3GPP2 and its Organizational Partners to incorporate text or other copyrightable material contained The contributors grants a free, irrevocable license to 3GPP2 and its Organizational Partners to incorporate text or other copyrightable material contained in the contribution and any modifications thereof in the creation of 3GPP2 publications; to copyright and sell in Organizational Partner's name any in the contribution and any modifications thereof in the creation of 3GPP2 publications; to copyright and sell in Organizational Partner's name any Organizational Partner's standards publication even though it may include all or portions of this contribution; and at the Organizational Partner's sole Organizational Partner's standards publication even though it may include all or portions of this contribution; and at the Organizational Partner's sole discretion to permit others to reproduce in whole or in part such contribution or the resulting Organizational Partner's standards publication. contributors discretion to permit others to reproduce in whole or in part such contribution or the resulting Organizational Partner's standards publication. contributors is also willing to grant licenses under such contributor copyrights to third parties on reasonable, non-discriminatory terms and conditions for purpose of is also willing to grant licenses under such contributor copyrights to third parties on reasonable, non-discriminatory terms and conditions for purpose of practicing an Organizational Partner's standard which incorporates this contribution. practicing an Organizational Partner's standard which incorporates this contribution. This document has been prepared by contributors to assist the development of specifications by 3GPP2. It is proposed to the Committee as a basis for This document has been prepared by contributors to assist the development of specifications by 3GPP2. It is proposed to the Committee as a basis for discussion and is not to be construed as a binding proposal on contributors. contributors specifically reserves the right to amend or modify the material discussion and is not to be construed as a binding proposal on contributors. contributors specifically reserves the right to amend or modify the material contained herein and to any intellectual property of contributors other than provided in the copyright statement above.contained herein and to any intellectual property of contributors other than provided in the copyright statement above.

2

• Single carrier multilink overview• Simulation methodology• Simulation results

Outline

3

Legacy HRPD operation

4

SCML in HRPD – No feedback sharing

5

Advantages of feedback sharing in SCML

6

# DESCRIPTION PARAMETER

1 Cell Layout 7-cells, 21 sectors, wrap-around

2 Large scale terrain model Urban Macro , (COST 231 from 3gpp2)

3 Tx Power, Height, Antenna Tilt, Antenna Gain 40 dBm, 32m, 4degree, 15dB

4 Inter Site Distance 1.2 km

5 UE Height 1.5m

6 Carrier frequency (fc) 2GHz

7 No. of carrier per sectors 1 (1.25MHz)

8 Maximum allowed active users/sector 20

9 AT distribution Spatially Uniform distribution across the cell

10 AT numbers across cells Heavily loaded cell: 20 ATs per sectorLightly loaded cell: 8 ATs per sector1 Cell is heavily loaded, Remaining cells are lightly loaded.

11 AT mobility Vehicular speeds distribution per the 3GPP2 evaluation methodology, C.R1002-B

12 Max. forward links per user in SCML mode 2

13 T_ADD between active connection to enable SCML 6dB

Simulation assumptions - 1

7

# DESCRIPTION PARAMETER

14 Fast Fading Channel Models between Tx and Rx 3GPP2 Channel Mixer3GPP2 C.R1002-B Evaluation Methodology

15 SCML Source Switching Disabled AT does not change the SCML sources.

16 Traffic profile Full Buffer

17 Scheduler Proportional Fair (Independent at each Sector)

18 Proposed Schemes to be compared

Baseline(Independent (PF) schedulers at the SCML sources)

PF_metric(n) = R(n)/A(n), for the nth slotR (n) = Requested Rate based on DRC applicable at the nth slotA(n) = Avg. throughput delivered to the AT at the nth slot

SCML with instantaneous throughput exchange PF_metric(n) = R(n)/A(n), for the nth slotR (n) = Requested Rate based on DRC applicable at the nth slotA(n) = A(n) + Ar(n)Ar(n) = Received value of Avg. Throughput delivered to the AT through the other sector

SCML with periodic throughput exchange PF_metric(n) = R(n)/A(n), for the nth slotR (n) = Requested Rate based on DRC applicable at the nth slotA(n) = A(n) + Ar(x), x = floor(n/p) where p is periodicity of exchangeAr(n) = Received value of Avg. Throughput delivered to the AT through the other sector

Simulation assumptions - 2

Simulation Results

9

• Throughput for each AT, t(u) = (Total Bits delivered)/ (Duration of simulation), where u - AT1, AT2, ..

• Throughput metric, T = mean(t(u))

• AT Load distribution across cells is as followso 1 Cell is heavily loaded (HL) (here  cell_1 is HL)

o Remaining 6 cells are lightly loaded (LL)

• Throughput metric(T) is evaluated for different sets of ATs1. T(SCML ATs) in HL cells

2. T (Non-SCML ATs) in HL cells

3. T (All ATs) in HL cells

4. T(SCML ATs) in All cells

5. T (Non-SCML ATs) in All cells

6. T (All ATs) in All cells

Understanding the results

10

• Baseline – No SCML, Single carrier Rev-A EVDO operation• SCML – without sharing• SCML – with Instantaneous sharing of feedback• SCML with Feedback sharing

• Periodicity -> 100 slots (167 ms)• Periodicity -> 200 slots (334 ms)• Periodicity -> 300 slots (501 ms)

Scenarios

11

Throughput metrics (in

Kbps)

Baseline

(kbps)

SCML without

throughput

sharing(kbps)

SCML with Inst.

Sharing(kbps)

% gain-SCML

with no sharing

(%)

% gain-SCML with

instantaneous

sharing(%)

SCML ATs in Cell_1 13.8499 36.596 30.3457 164.233 119.1041

Non-SCML ATsIn Cell_1 64.3558 60.2906 70.5487

-6.31676 9.622909

All ATs In Cell_1 45.7874 50.4179 53.7975

10.11304 17.49411

SCML ATs (across all

cells) 29.2345 46.1232 40.994257.7697

6 40.22542Non-SCML ATs

(across all cells) 88.0766 64.3773 80.4118

-26.9076 -8.70242

All ATs (across all

cells) 64.7128 57.1293 64.7607-

11.7187 0.074019

Gains due to throughput sharing with SCML

12

Throughput metrics (in

Kbps)

SCML without

throughput

sharing(kbps)

SCML with Inst.

Sharing(kbps)

Change due to sharing(kbps)

Change due to sharing

(%)

SCML ATs in Cell_1 36.596 30.3457 -6.2503 -17.0792

Non-SCML ATsIn Cell_1 60.2906 70.5487 10.2581 17.01443All ATs In Cell_1 50.4179 53.7975 3.3796 6.703175

SCML ATs (across all

cells) 46.1232 40.9942 -5.129 -11.1202Non-SCML ATs

(across all cells) 64.3773 80.4118 16.0345 24.90707

All ATs (across all

cells) 57.1293 64.7607 7.6314 13.35812

Impact of throughput sharing with SCML

13

Comparison of throughput metrics

1. Gains for SCML ATs in Cell_1 (HL Cell) is higher compared to the gain of SCML ATs averaged over the entire network

2. Without throughput sharing, Non-SCML ATs suffer losses w.r.t to the baseline

3. With throughput sharing,• Loss to Non-SCML ATs is reduced significantly • Minor reduction in gains to SCML ATs.

14

Throughput metric, T (in kbps)

Baseline(kbps)

SCML without throughput sharing(kbps)

Inst. Sharing(kbps)

p = 100 slots, ~167 ms(kbps)

p = 200 slots, ~334ms(kbps)

p = 300 slots, ~501 ms(kbps)

SCML ATs in Cell_1 13.8499 36.596

30.3457 30.4965 31.0971 31.6006

Non-SCML ATs

In Cell_1 64.3558 60.290670.548

7 67.9509 68.7169 65.6316All ATs In Cell_1 45.7874 50.4179

53.7975 52.3449 53.042 51.452

SCML ATs (across all

cells) 29.2345 46.123240.994

2 40.1901 40.7787 39.8772Non-SCML

ATs(across all

cells) 88.0766 64.377380.411

8 79.5634 79.8793 76.4182All ATs

(across all cells) 64.7128 57.1293

64.7607 63.9299 64.3541 61.9093

Comparison of throughput metrics with periodicity, p = 100, 200, 300 slots

15

Comparing throughput metrics for throughput sharing at different periodicities

16

(Percentage gains as compared to baseline)

SCML without

throughput sharing

(%)

Inst. Sharing(%)

Per 100 slots, ~167 ms(%)

Per 200 slots, ~334 ms(%)

Per 300 slots, ~501 ms(%)

SCML ATs in Cell_1 164.233 119.1041 120.1929 124.5294 128.1648

Non-SCML ATsIn Cell_1 -6.31676 9.622909 5.586287 6.776545 1.982417All ATs In Cell_1 10.11304 17.49411 14.32163 15.8441 12.37153

SCML ATs (across all

cells) 57.76976 40.22542 37.4749 39.48828 36.40459Non-SCML ATs

(across all cells) -26.9076 -8.70242 -9.66568 -9.30701 -13.2367

All ATs (across all

cells) -11.7187 0.074019 -1.20981 -0.5543 -4.33222

Comparison of percentage gains with periodicity, p = 100, 200, 300 slots

17

• SCML leads to gain for cell-edge users (that can get into SCML mode)

• Non-SCML users suffer losses during SCML operation – cost of gain for cell-edge users

• Losses to Non-SCML users can be mitigated by feedback sharing• Feedback sharing can be used to balance gains between the Non-

SCML and SCML users• The gains to SCML users due to feedback sharing at different

periodicities are comparable same as with instantaneous throughput sharing

• Feedback sharing periodicity can be tuned based on considerations of backhaul requirements

Discussion and Summary

18

Thanks