采用LDPC码方案的战术数据链系统

摘要

战术数据链系统能够提高部队信息化作战能力,其中信道编码技术是保证消息传输可靠性的关键技术之一.构建了一种新的战术数据链系统,系统采用低密度奇偶校验（LDPC,Low-Density Parity-Check）码方案,LDPC码是适用于传输可靠性要求高的通信系统的新型码组.介绍了LDPC码方案中的和积算法,描述了系统的传输模型,分析了系统在固定频率和加性白色高斯噪声（AWGN,Additive White Gaussian Noise）信道条件下的链路性能.利用计算机进行蒙特卡罗仿真,结果表明：在AWGN信道和瑞利衰落信道下,LDPC编码方案可以有效地降低数据链系统的误比特率,取得比采用里德.所罗门编码的联合战术信息分发系统更好的误码性能.LDPC码作为信道编码技术的备选码组,为进一步提高战术数据链的可靠性提供了一种解决方案.%In information warfare,military combat capability can be improved by tactical data link system of which coding is one of crucial techniques of the transmission reliability.A new type of tactical data link system was proposed employing low-density parity-check（LDPC） code scheme,which is a new set of codes for communication systems demanding intensive reliability.The sum-product algorithm of the LDPC code scheme was introduced and the transmission model was described.Then the link performance of the system within the fix frequency over additive white Gaussian noise（AWGN） channel was analyzed.Simulation results with Monte-Carlo method show that the LDPC code scheme can decrease the bit error rate of the tactical data link system effectively.The results also showe that the LDPC-coded data link system achieves better performance than joint tactical information distribution system（JTIDS）,which employe Reed Solomon codes as channel coding scheme,over AWGN channel and Rayleigh fading channel.LDPC codes,serving as the alternative codes for channel coding technique,provide possible solutions to enhance the transmission reliability of tactical data link system.