【作者】 刘健；

【导师】 周希元；

【作者基本信息】 西安电子科技大学 ， 通信与信息系统， 2010， 博士

【摘要】 信道编码的盲识别是在未知编码信息的条件下仅根据接收到的编码数据来快速识别编码结构,在信号截获、协作通信、智能移动通信、多点广播通信等领域具有重要而广泛的应用,已经成为该领域理论与技术研究的前沿问题和研究热点,对该技术进行研究具有重要的理论意义和应用价值。论文正是围绕这一方向开展的。本文取得的主要研究成果与创新点有：(1)针对系统二进制线性分组码,提出了基于线性空间变换的二进制线性分组码的盲识别。在误码较高,码长较短时,通过Walsh-Hadamard变换求解校验矩阵来完成二进制线性分组码的盲识别。理论分析和仿真实验均验证了提出算法的有效性。理论证明了二进制线性分组码通过分组交织后仍为一个二进制的线性分组码,完成了无误码情况下分组码的分组交织的识别,为有误码情况下分组码的分组交织提供了理论基础。(2)根据二进制BCH码的循环特性,提出了基于欧几里得算法的二进制BCH码的盲识别,该算法计算复杂度低且具有一定的容错能力。(3)首次提出了非二进制信道编码的盲识别算法,通过在伽罗华域对待识别RS码进行傅立叶变换来完成含错RS码的盲识别。理论分析和仿真实验均验证了提出算法可以在含错码的情况下对RS码进行有效识别。(4)对于扩展Golay码,通过挑选偶数重量的码字来规避部分误码分组,进而降低误码对待识别分组的影响。仿真实验表明,在误码率相同的情况下,较现有算法而言,提出算法的正确识别概率具有显著的提高。(5)针对(2,1,m)卷积码,提出了基于Walsh-Hadamard变换的卷积码的盲识别方法。较现有算法而言,提出算法具有一定的容错性能。通过将截获数据进行分路处理,首次提出了非系统含错(n,1,m)卷积码和系统含错(n,k,m)卷积码的盲识别算法,向任意参数卷积码的盲识别迈进了一大步。(6)针对DVB-S系统中的删除卷积码的盲识别问题,提出了基于先验校验向量的删除卷积码的盲识别算法,仿真实验表明在保证估计可靠性的前提下,该算法的估计时间可以降低到传统算法估计时间的10%。更多还原

【Abstract】 Blind recognition of the channel coding is that under the conditions of unknown encoding information, only in accordance with the unknown encoded data, it requires the receiver quickly recognize the system and the parameters of channel coding. It is widely used in information interception, cooperation communication, intelligent mobile communication, multicast communication and other fields of digital communication system. And it has become frontier issue and research hot spot in this field. Therefore, it is of great importance in both theory and practice. And the paper is spread around this direction.The primary achievement and innovation points of the thesis are as follows:(1) An algorithm of blind recognizing the binary linear block codes based on the linear space transformation is presented. In the high error rate condition, the Walsh-Hadamard transform can be used to solve the parity check matrix of the short length binary linear block codes. The theoretical analyses and simulation experiment demonstrate the effectiveness of the proposed algorithm. It is proved that the binary linear block codes passing block interleaver are still binary linear block codes. Blind recognition of block interleaving without errors is also achieved, which provided theoretical basis for block interleaving of block code with errors.(2) Because the binary BCH codes are cyclic, an algorithm based on Euclidean algorithm to blind recognize the binary BCH codes is proposed in this paper. The proposed algorithm is error-resilient in a certain extent and the computation complexity is low.(3) An algorithm of blind recognizing the non-binary codes is proposed for the first time in this paper. Based on the Galois Field Fourier Transform (GFFT) of codes with errors, the RS codes can be recognized. The theoretical analysis and simulation validate the effectiveness of the proposed algorithm.(4) For the extended Golay codes, a blind recognition algorithm based on finding codewords with even hamming weights to avoid some error block, and thus reduce the effect of error on the codewords is proposed in this paper. The simulation shows that the correct recognition rate of the proposed algorithm is significantly higher than that of the existing algorithms under the same bit error rate. (5) A blind recognition algorithm of (2,1,m) convolutional codes based on the Walsh-Hadamard transform is proposed. The proposed algorithm is error-tolerant in a certain extent compared with the existing algorithms. Blind recognition algorithms of the nonsystematic (n,1,m) convolutional codes with errors and the systematic (n,k,m) convolutional codes with errors are proposed for the first time, which makes it closer to practical application of the blind recognition of the general convolutional codes.(6) A fast algorithm based on prior parity-check vector to blind recognize the punctured convolutional codes in digital video broadcast satellite (DVB-S) receiving system is proposed. The simulation experiment shows by using the proposed algorithm the estimating time can be reduced to 10% of the traditional algorithm with the reliable estimation.更多还原