Zhu dengkui,Jerry Chow E-mail: Zhu.dengkui@zte.com.cn UL HARQ Feedback Channel Performance Comparisons of tile Format Options Document Number: C80216m-09_0158 Date Submitted: 2009-01-05 Source: Zhu dengkui,Jerry Chow E-mail: Zhu.dengkui@zte.com.cn *<http://standards.ieee.org/faqs/affiliationFAQ.html> Venue: To Response “Call for Contributions on Project 802.16m System Description Document (SDD) – pertaining to comment on entire content of IEEE 802.16m-08/003r6.”, “section 11.9.2.2 UL HARQ Feedback Channel” Base Contribution: Purpose: To be accepted by TGm. 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/sect6-7.html#6> and <http://standards.ieee.org/guides/opman/sect6.html#6.3>. Further information is located at <http://standards.ieee.org/board/pat/pat-material.html> and <http://standards.ieee.org/board/pat >.

Background There exist several possible multiplexing unit format in the HARQ feedback channel: 2x6, 6x2, and 1x2 format Different pilot patterns Considerations Detection error performance vs. channel conditions Frequency selective, time selective FDM legacy support

UL Tile Structure Alternatives 3 3 3

Simulation Setup Parameters Value FFT Size 1024 Bandwidth 10 MHz Carrier frequency 2.5 GHz Number of transmit antennas 1 Number of receiver antennas 2 Resource block 18subcarriers x 6 OFDM symbols Receiver Type Coherent/Non-Coherent Channel Model Ped B – 3 km/h Veh A – 120 km/h, 350 km /h The correlation of channel Antenna Interval: 4 λ, AS:5degree at BS SNR E/N0 per subcarrier 4

Performance Results – Veh A (120 km/h) 5

Performance Results – Veh A (350 km/h) 6

Observations & Conclusions 6x2 structure is equal to or better than 2x6 over all MS speeds 6x2 structure performs significantly better at very high MS speeds. 6x2 is not compatible with FDM with PUSC mode of UL legacy support. For the format 1*2,although channels not changes notablely in the 2 symbols at high mobile speed, its deadly because of its short sequence, so the 1*2 shows a certain performance degrade than the 6*2 tile structure. Need 2x6 only for FDM legacy support but 6x2 should supported for other UL configurations due to significant performance advantages In order to capture the frequency diversity gain, DRU is used in HARQ feedback channel, where each tile of DRU is consist of three FMTs. 7

Proposal Text We suggest to change the following current description 11.9.2.2.2 PHY structure We suggest to change the following current description “The UL HARQ feedback channel is comprised of three distributed UL feedback mini-tiles (FMT), where the UL FMT is defined as 2 contiguous subcarriers by 6 OFDM symbols. A UL FMT of 6 contiguous subcarriers by 2 OFDM symbols is FFS. One LRU consists of 9 FMTs and can be shared by multiple HARQ feedback channels.” to “The UL HARQ feedback channel is comprised of three distributed UL feedback mini-tiles (FMT). One UL FMT is defined as 6 contiguous subcarriers by 2 OFDM symbols in the 16m-only frame or the mixed frame with UL TDM. And one UL FMT of 2 contiguous subcarriers by 6 OFDM symbols is used in the mixed frame with UL FDM. One LRU consists of 3 tiles where each tile consists of 3 FMTs, and can be shared by multiple HARQ feedback channels.