【摘要】 纠错码是现代通信系统中抵抗无线衰落信道噪声和干扰不可或缺的标准技术,对纠错编码性能的研究一直是通信技术的热门问题。为了提高纠错码的编译码性能,提出了一种结合重复累积(RA)码和级联树(CT)码的累积重复树(ART)码方案,研究了编码结构和译码算法,分析了密度进化方法,推导了高斯近似实现算法,讨论了与OFDM调制相结合的无线网络应用模式。对不同信道条件下的译码性能进行了仿真和比较分析,结果表明,ART码具有较高的编码增益,且编译码算法简单,采用置信传播(BP)译码算法的ART码性能出色。更多还原

【Abstract】 It is an indispensable standard technology for error correcting codes to defend jam and noise of wireless fading channels in modern communication systems, which has made this technology become very popular all the time. And as a result of that, in this paper, an improved error correcting coding scheme called accumulate repeat tree( ART) codes, which were constructed based on repeat accumulate( RA) codes and concatenated tree( CT) codes, was proposed for enhancing the encoding and decoding performance.The encoding structure and decoding algorithm were studied. The density evolution principle was discussed, and the practicable al-gorithm of Gaussian approximation for ART codes was presented. An application of ART coded OFDM modulation is discussed in wireless networks. The simulation results show that ART codes have perfect encoding gain and simpleness of both encoding and decoding algorithm. At the same time, they show good performance improvement using belief-propagation( BP) decoding algorithm on different channel condition.更多还原