1. ProjectIEEE 802.16 Broadband Wireless Access Working Group http://ieee802.org/16 TitleCTC Bit grouping for IEEE 802.16m Amendment Document Number IEEE S802.16m-09/0665 Date Submitted 2009-03-09 Source(s)Jung Woon Lee, Zhigang Rong Huawei Seunghoon Choi, Chiwoo Lim, Songnam Hong, Sung-Eun Park Samsung Electronics, Co., Ltd. Zheng Zhao Samsung China Telecom R&D center CiouPing Wu, Peikai Liao, Paul Cheng MediaTek Inc. Du Ying, Luo Zhendong CATR Voice: 1-972-543-5880 E-mail: jwlee@huawei.comjwlee@huawei.com Voice: +82-31-279-5890 E-mail: seunghoon.choi@samsung.comseunghoon.choi@samsung.com E-mail: ciouping.wu@mediatek.comciouping.wu@mediatek.com E-mail:duying@mail.ritt.com.cn,duying@mail.ritt.com.cn luozhendong@mail.ritt.com.cn Re:IEEE 802.16m-09/0012, “Call for Contributions on Project 802.16m Amendment Working Document (AWD) Content”. Target topic: “ Channel Coding and HARQ ” AbstractWe propose new CTC Bit grouping schemes for IEEE 802.16m amendment. PurposeFor discussion and approval by TGm. for the 802.16m amendment 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: and.http://standards.ieee.org/guides/bylaws/sect6-7.html#6http://standards.ieee.org/guides/opman/sect6.html#6.3 Further information is located at and.http://standards.ieee.org/board/pat/pat-material.htmlhttp://standards.ieee.org/board/pat

2. Current 16e subblock interleaver All encoded symbols are split into 6 subblocks, A, B, Y1, Y2, W1, W2 Each subblock is interleaved independently with BRO operation Formed to 4 interleaved blocks A, B, Y1/Y2, W1/W2, where Y1/Y2 and W1/W2 are symbol-by-symbol multiplexed sequence of Y1&Y2 and W1&W2, respectively. Interleaved sequences are modulated sequentially

3. Current 16e subblock interleaver

4. Current 16e structure Problem - There are 3 layers protection class for 64 QAM (Best: b 2 & b 5, Good: b 1 & b 4, Worst b 0 & b 3 ) - Mapping the interleaved bit into 64QAM constellation isn’t optimized - Systematic bits and their parity mapped into worst layer are always mapped into worst or good layer in form of burst. - Turbo decoder performance is degraded as a pair bits (systematic, parity) are always mapped into same layer position in 64QAM constellation. - Input burst mapped into worst layer make the decoder performance worse

5. 64QAM constellation b 2 & b 5 : Best layer b 1 & b 4 : Good layer b 0 & b 3 : Worst layer

6. Mapping example (Nep=384, R=1/3, 64QAM) Sequence of A(0, 1, …, 63) and B(0, 1, …, 63) and their parity sequences Y1(0, 1, …, 63) and W1(0, 1, …, 63) are always mapped into best layer (b 2 or b 5 ) according to current sub- block interleaver design as shown in the attachment (below zip file) Sequences of A(64, 65, …, 127) and B(64, 65, …, 127) are mapped into good layer (b 1 or b 4 ) and their parity sequence Y1(64, 65, …, 127) and W1(64, 65, …, 127) are mapped into worst layer (b 2 or b 5 ) Sequences of A(128, 129, …, 191) and B(128, 129, …, 191) are mapped into worst layer (b 0 or b 3 ) and their parity sequence Y1(128, 129, …, 191) and W1(128, 129, …, 191) are mapped into good layer (b 1 or b 4 )

7. Proposed Subblock interleaver

8. Proposed Subblock interleaver (Cont’) where C is modulation order, R=  N/C , R 1 =  2N/C . δ = 1 for 64QAM and δ = 0 for other modulation. A i (j), B i (j), Y1/Y2 i (j) and W2/W1 i (j) are the permutation formula for j -th element of i -th group of interleaved sub-block I(A) I(B), I(Y1/Y2) and I(W2/W1), respectively Subblock interleaver is same as 16e C-symbol Permutation formula for the proposed subblock interleaver

9. Conclusions New scheme has up to 2.2 dB gain at (R=1/3, 64QAM), 1.0 dB gain at (R=1/2, 64QAM) and 0.6dB gain at (R=2/3, 64QAM). In 16QAM, new schemes has up to 0.4dB gain

10. Simulation Parameters Channel Model: AWGN Turbo decoder: Max-log-map with 8 iterations Packet size: 48, 144, 256, 288, 384, 512, 960, 1216, 1920, 2048, 2880, 3840, 4800 Code Rate: 1/3, 1/2, 2/3

11. Simulation Results