Performance of degree distribution based HARQ scheme for LDPC-coded OFDM system  

作　　者：LI Xue-hua CAO Yi-qing LI Zhen-song YANG Da-cheng 

机构地区：[1]Communication Engineering Department, Beijing Information Science and Technology University, Beijing 100101, China [2]Wireless Theories and Technologies Lab (WT&T), Beijing University of Posts and Telecommunications, Beijing 100876, China

出　　处：《The Journal of China Universities of Posts and Telecommunications》2009年第1期47-50,共4页中国邮电高校学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (60501007).

摘　　要：This article studies the degree distribution property of low density parity check （LDPC） codes by Gaussian approximation （GA） and presents an efficient hybrid automatic repeat quest （HARQ） scheme for LDPC-coded orthogonal frequency division multiplexing （OFDM） system. In the scheme, the important bits with large degrees have high retransmission priorities and are mapped to the sub-carriers with better channel quality indicator （CQI） levels in the OFDM system. The new scheme provides more protection to the bits with large degrees and thus contributes more to the decoding process by offering more transmission power. In this way the system performance would be improved. The statistics and simulation results also prove the new scheme.This article studies the degree distribution property of low density parity check （LDPC） codes by Gaussian approximation （GA） and presents an efficient hybrid automatic repeat quest （HARQ） scheme for LDPC-coded orthogonal frequency division multiplexing （OFDM） system. In the scheme, the important bits with large degrees have high retransmission priorities and are mapped to the sub-carriers with better channel quality indicator （CQI） levels in the OFDM system. The new scheme provides more protection to the bits with large degrees and thus contributes more to the decoding process by offering more transmission power. In this way the system performance would be improved. The statistics and simulation results also prove the new scheme.

关 键 词：LDPC codes HARQ degree distribution GA OFDM 

分 类 号：TN941.4[电子电信—信号与信息处理] TN929.5[电子电信—信息与通信工程]