ERASED-CHASE DECODING FOR RS-CODED MPSK SIGNALING OVER A RAYLEIGH FADING CHANNEL  

作　　者：Xu Chaojun Sun Yue Wang Xinmei 

机构地区：[1]State Key Lab. of Integrated Service Networks, Xidian University, Xi＇an 710071, China

出　　处：《Journal of Electronics(China)》2007年第3期296-300,共5页电子科学学刊（英文版）

基　　金：the National Natural Science Foundation of China (No.60272057).

摘　　要：In this paper,a novel dual-metric,the maximum and minimum Squared Euclidean Distance Increment (SEDI) brought by changing the hard decision symbol,is introduced to measure the reli-ability of the received M-ary Phase Shift Keying (MPSK) symbols over a Rayleigh fading channel. Based on the dual-metric,a Chase-type soft decoding algorithm,which is called erased-Chase algorithm,is developed for Reed-Solomon (RS) coded MPSK schemes. The proposed algorithm treats the unre-liable symbols with small maximum SEDI as erasures,and tests the non-erased unreliable symbols with small minimum SEDI as the Chase-2 algorithm does. By introducing optimality test into the decoding procedure,much more reduction in the decoding complexity can be achieved. Simulation results of the RS(63,42,22)-coded 8-PSK scheme over a Rayleigh fading channel show that the proposed algorithm provides a very efficient tradeoff between the decoding complexity and the error performance. Finally,an adaptive scheme for the number of erasures is introduced into the decoding algorithm.In this paper, a novel dual-metric, the maximum and minimum Squared Euclidean Distance Increment （SEDI） Brought by changing the hard decision symbol, is introduced to measure the reliability of the received M-ary Phase Shift Keying （MPSK） symbols over a Rayleigh fading channel. Based on the dual-metric, a Chase-type soft decoding algorithm, which is called erased-Chase algorithm, is developed for Reed-Solomon （RS） coded MPSK schemes. The proposed algorithm treats the unreliable symbols with small maximum SEDI as erasures, and tests the non-erased unreliable symbols with small minimum SEDI as the Chase-2 algorithm does. By introducing optimality test into the decoding procedure, much more reduction in the decoding complexity can be achieved. Simulation results of the RS（63, 42, 22）-coded 8-PSK scheme over a Rayleigh fading channel show that the proposed algorithm provides a very efficient tradeoff between the decoding complexity and the error performance. Finally, an adaptive scheme for the number of erasures is introduced into the decoding algorithm.

关 键 词：Reed-Solomon （RS） codes Coded M-ary Phase Shift Keying （MPSK） Rayleigh fading Dual-metric Chase decoding 

分 类 号：TN911.22[电子电信—通信与信息系统]