Research On Blind Recognition Technology For Channel Coding

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.