Improved Partitioned Fast-SSC-Flip Decoding for Polar Codes

The error correction performance of the polar codes under successive cancellation (SC) decoding is unsatisfactory for the finite code lengths. The SC-flip is introduced to improve the error correction performance of SC decoding. The SC-flip decoding considers the absolute log-likelihood ratios of the entire nonfrozen bits to identify wrong decisions. Moreover, its error correction performance cannot outperform the cyclic redundancy check-aided SC-list (L = 2). In this work, we propose an error-prone flipping list (FL) by incorporating the indices that are observed based on channel-induced error distribution and the first bit of each Rate-1 node, thus substantially narrowing down the search span for the identification of the first erroneous location. Furthermore, we merge the partitioned SC-flip idea with the high-speed SC-flip decoders and propose an improved partitioned fast-SSC-flip (PFSSC-flip) decoder. Simulation results show that at SNR = 3dB, the improved PFSSC-flip has 0.8dB and 0.25dB gains over fast-SSC and fast-SSC-flip decoders, respectively.