用于水声相干通信系统的联合迭代均衡和译码算法

摘要

Serially concatenated trellis coded modulation ( SCTCM) technology is adopted to improve the bandwidth efficiency of the underwater acoustic channel. In order to overcome multi-path fading and eliminate inter-symbol interference (1SI), the turbo theory is applied to form the joint iterative multi-channel adaptive decision feedback equalizer ( MC-ADFE) and decoder of SCTCM. In the joint iterative equalization and decoding (JIED) algorithm, the MC-ADFE and decoder of SCTCM exchange soft information in an iterative manner, which can enhance the equalizer performance using the significant decoding gain. Simulation results show that the proposed system scheme can improve the performance of the equalizer and lead to a considerable coding gain. So, the performance of the underwater acoustic communication system has been improved greatly.%采用串行级联网格编码调制(SCTCM)技术,高效利用带宽受限的水声信道带宽.同时,为了克服水声信道时变多途衰落,消除码间干扰,运用Turbo迭代原理构建多通道自适应均衡器和SCTCM译码器联合迭代算法.在联合迭代均衡和译码(JIED)算法中,均衡器和译码器通过迭代的方式,交换数据符号的软信息来改善均衡器的性能,从而实现高速、可靠的数据传输.计算机仿真结果表明,使用上述体制的水声通信系统,在高效利用水声信道带宽的同时,利用译码器提供的译码增益,提高了均衡器的数据处理能力,通信系统接收数据的误码率降低了两个数量级.