Blind Recognition of BCH and RS Codes With Small Samples Intercepted Bitstream

In non-cooperative communication systems, effective parameter identification with small samples intercepted bitstream is a major challenge. Faced with this demand, a solution to blind recognition for BCH and RS codes is presented. Firstly, the intercepted bitstream is analyzed, and the optimal code-set with high reliability is selected by channel soft information. Secondly, the optimal code-set is cycled into a pseudo cyclic matrix according to the algebraic structure of the codewords, which is employed for the code length and synchronization recognition based on the improved rank criterion. Finally, the code spectrum analysis of the optimal code-set is performed to complete primitive and generator polynomial recognition, and a recoding operation is proposed to judge the recognition performance. Simulations validate the proposed algorithms by recognition probability in terms of different parameters, it hardly depends on the number of codewords but on the accuracy of the optimal code-set, which is especially suitable for small sample datasets. Under the Additive White Gaussian Noise (AWGN) channel with Binary Phase-Shift Keying (BPSK) modulation, the recognition probability is still comparable to or superior to the existing schemes, even if only one-twentieth of the intercepted codewords are used.