Comparison Between FDM and CDM Sounding Methods Document

Comparison Between FDM and CDM Sounding Methods Document Number: IEEE C 802. 16 m-09/0979 r 1 Date Submitted: 2009 -05 -05 Source: Chih-Yuan Lin (chihyuan. lin@mediatek. com), Pei-Kai Liao (pk. liao@mediatek. com ), Yu-Hao Chang (yuhao. chang@mediatek. com), Ciou-Ping Wu (ciouping. wu@mediatek. com), and Paul Cheng (paul. cheng@mediatek. com) Media. Tek Inc. Venue: Category: AWD comments / Area: Chapter 15. 3. 9 (Uplink Control Channel) “Comments on AWD 15. 3. 9. 2. 3. 2 (Multiplexing for Multi-antenna and Multi-AMS)” Base Contribution: N/A Purpose: Propose to be discussed and adopted by TGm for the use in Project 802. 16 m AWD Notice: This document does not represent the agreed views of the IEEE 802. 16 Working Group or any of its subgroups. It represents only the views of the participants listed in the “Source(s)” field above. It is offered as a basis for discussion. It is not binding on the contributor(s), who reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802. 16. Patent Policy: The contributor is familiar with the IEEE-SA Patent Policy and Procedures: <http: //standards. ieee. org/guides/bylaws/sect 6 -7. html#6> and <http: //standards. ieee. org/guides/opman/sect 6. html#6. 3>. Further information is located at <http: //standards. ieee. org/board/pat-material. html> and <http: //standards. ieee. org/board/pat >.

Two Comparative Methods ▪ FDM and CDM examples FDM: Frequency decimation CDM Length-6 Zadoff-Chu cod

Simulation Parameters ▪ Simulation parameters – Noise-limited scenario • 6 serving AMSs • For CDM, length-6 Zadoff-Chu sequences – Interference-limited scenario (SNR = inf) • 6 serving AMSs and 6 interfering AMSs • Interference power is equally assigned to 6 interfering AMSs (see Appendix II for illustration) – SIR = (total received signal power) / (total received interference power over 18 subcarriers) • For CDM, use length-6 Zadoff-Chu sequences and generate two binary random sequences for masking two cells – Channel estimation: 2 D-MMSE • Optimized to predefined velocity speed 3 km/hr • Optimized to predefined channel delay spread 5 us – Channel model • PB 3 km/hr – Performance metric • Tone-wise channel estimation mean square error (at data tones of a

Simulation Results (1/3) ▪ Noise-limited scenario

Simulation Results (2/3) ▪ Interference-limited scenario

Simulation Results (3/3) ▪ Noise-limited scenario – Power imbalance happens between six users • MS 2 = MS 1+1 d. B, MS 2 = MS 1+3 d. B, MS 2 = MS 1+5 d. B, MS 2 = MS 1+8 d. B, MS 2 = MS 1+10 d. B • MS 1 is weakest and following result is the MS 1’s MSE Power imbalance has no effect on FDM, but affects CDM a lot

Conclusion ▪ In noise-limited and interference-limited scenarios, FDM performs better than CDM ▪ Suggest only keeping FDM for sounding multiplexing

Text Proposal ▪ 15. 3. 9. 2. 3. 2 Multiplexing for multi-antenna and multi-AMS The uplink sounding channels of multiple AMS and multiple antennas per AMS can be multiplexed through [Option 1: decimation separation or cyclic shift separation] decimation separation in each sounding allocation. Also, in case of multiple UL subframes for sounding, time division separation can be applied by assigning different AMS to different UL subframe. For cyclic shift separation each AMS occupies all subcarriers within sounding allocation and uses the different sounding waveform [Editor's note: remove this sentence if Option 2 will be adopted]. For frequency decimation separation each AMS uses decimated subcarrier subset from the sounding allocation set with different frequency offset. For antenna switching capable AMS, ABS can command the AMS to switch the physical transmit antenna(s) for sounding transmission. The details for supporting antenna switching on sounding is TBD.

Appendix I ▪ Channel estimation for CDM sounding Used for 2 D-MMSE channel estimation

Appendix II ▪ SIR definition