Cascaded polarization code bit inverting belief propagation encoding and decoding method

Abstract

The cascaded polarization code bit inverting belief propagation encoding and decoding method is suitable for being used in the technical field of channel encoding in wireless communication, messages are transmitted between LDPC and polarization codes through a BP decoding method, and the correct rate of information transmission through an unreliable channel is increased; under the condition that BP decoding fails, a bit inverting decoding method is used for selecting unreliable information bit judgment through a pre-constructed key set, and the prior log-likelihood ratio of unreliable channelinformation bits is set to be an infinite value; by trying to correct error information propagation in the BP decoder, the error rate performance of the cascade code under the BP decoding method is improved. According to the method, the accuracy of key set inverting is effectively improved, the group error rate can be greatly improved, and the group error rate performance is remarkably improved; and meanwhile, the decoding time delay is not increased, and the gain of the bit error rate performance can be obtained at the cost of relatively small decoding time delay.

Description

technical field [0001] The invention relates to a coding and decoding method, in particular to a coding and decoding method of concatenated polar code bit inversion belief propagation in the technical field of channel coding in wireless communication. Background technique [0002] When the code word length is infinite, the transmission rate of the polar code under the decoding method of Successive Cancellation (SC) can reach the channel capacity of the binary input memoryless symmetric channel. However, the SC decoding method of polar codes is sequential decoding, and the decoding delay is relatively large. Another decoding method of polar codes is Belief Propagation (BP) decoding. Although the transmission rate of the polar code under BP decoding cannot reach the channel capacity, BP decoding can be iteratively calculated in parallel, and the decoding delay is significantly lower than that of the SC decoding method and is not sensitive to the codeword length, so BP decodin...

AI Technical Summary

Problems solved by technology

However, in the case of limited code length, due to the insufficient channel polarization of polar codes, the error rate performance of the traditional BP decoding method of polar codes is poor, and needs to be improved.

Using Low Density Parity Check code (Low Density Parity Check, LDPC) as the outer code to protect the unreliable channel with insufficient polarization, and the polarization code as the inner code to construct the concatenated code can improve the performance of the group error rate, but the actual use is still not ideal

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