Abstract:

In order to solve the problem of poor anti-noise performance in the current polar code length recognition, a blind recognition algorithm of polar code parameters based on information matrix estimation is proposed. In this algorithm, the inverse matrix of the polar code generation matrix is used to multiply with the code word matrix constructed by the code word bit stream to obtain the estimated information matrix. In the case of no error code, the bit rate is obtained according to the information contained in the analysis matrix, and its distribution is used to identify the code length, bit number and position distribution. In the case of bit error, zero mean ratio measurement is introduced to identify the code length according to the peak value. Finally, by using the analysis matrix and setting the decision threshold, the information bit number and position distribution are identified. The simulation results show that the recognition performance of the proposed algorithm for code length is improved. For the polar code with parameters of (64, 30), the recognition rate of code length can still reach 80% when the bit error rate is as high as 1.06×10^-1.

Key words: non-cooperative signal processing, zero mean ratio, polar code, blind recognition