Ordered statistics decoding of linear block codes on frequencynonselective multipath channels

摘要

This paper investigates the performance of ordered statisticsndecoding (OSD) of linear block codes with binary differentialnphase-shift-keying (2DPSK) transmission on frequency nonselectivenmultipath channels. First, the wireless channel is modeled as anfrequency nonselective, slow fading environment without intersymbolninterference. Second, block interleaving is embedded to decorrelate thensuccessive received symbols so that the performance of OSD, designednessentially for memoryless channels, is retained. Third, we derive thenlog-likelihood ratio of received symbols based on 2DPSK modulation.nFourth, we derive the statistics of received symbols and the statisticsnof received symbols after ordering. Further, we analyze the system errornperformance for sufficient degree of interleaving. Specifically, wenderive the asymptotic bit error rate (BER) of OSD at high SNRs using thenfirst-order approximation, finally, we conduct experiments at variousnchannel characteristics and interleaving degrees for (128, 61, 22)nextended BCH code and (24, 12, 8) extended Golay code. Results show thatnthe error performance improves tremendously with increased interleavingndegree