A Segment CRC Scheme for Polar Codes

In this paper, segment cyclic redundancy check (CRC) scheme for polar codes is discussed. Motivated by the non-monotonic property of the first error probabilities of bit-channels used for transmitting information bits and the sequential decoding property of list successive cancellation (LSC) decoding, we propose a segment CRC scheme for polar codes. Both the principle for dividing information sequence into multiple subsequences and decoding procedure are discussed. The analysis shows that the segment CRC scheme can improve the BLER performance of polar codes, reduce the decoding complexity with the cost of undetected error probability compared with conventional CRC scheme. The simulation results verify our analysis. Besides, we also show how different CRC combinations effect the BLER performance of polar codes by simulation. And the simulation result suggests that the last CRC in the CRC combination must be strong in order to find the correct path in the list.