Coding schemes incorporating soft-decision DPSK over HF Rayleigh fading channels

作     者：Dimakis, CE Nissopoulos, IK Kouris, SS 

作者机构：Aristotelian Univ Salonika Dept Elect Engn & Comp Engn Telecommun Div GR-54006 Salonika Greece 

出 版 物：《WIRELESS PERSONAL COMMUNICATIONS》 (无线个人通信)

年 卷 期：2001年第16卷第2期

页      面：95-113页

核心收录：

学科分类：0810[工学-信息与通信工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

主　　题：fading channels Trellis coded modulation concatenated coding differential phase shift keying interleaved coding 

摘      要：A soft-decision 8-DPSK modulation format is introduced in a concatenated coding scheme and the performance of the resulting system is evaluated over a slow Rayleigh fading HF ionospheric Link in the presence of Additive White Gaussian noise (AWGN). Well-known Ungerboeck TCM techniques are used as inner codes and a Reed-Solomon block code as outer code. The coded/modulated signal is differentially encoded before transmission to combat random phase changes caused by the channel. Soft-decision demodulator s output is used as an input to a modified Viterbi decoder that calculates the Euclidean distances of the received signal from an 8-PSK constellation adapted to the signal s amplitude variations. Block interleaving techniques are necessary to randomise long bursts of errors caused by the fading channel. Simulation results show that significant coding gains are achieved with a minor bandwidth expansion over uncoded, diversity or other coded systems. Finally, the interesting effects of interleaving on the performance of the proposed systems are analysed.