Termination for Belief Propagation Decoding of Polar Codes in Fading Channels.

In additive white Gaussian channel (AWGN), the performance of polar codes under the successive cancellation (SC) decoding is not as good as that of the belief propagation (BP) decoding. However, in a fading channel, the performance of BP decoding is found in our study to be worse than the SC decoding. In this work, we propose a termination criterion for the BP decoding of polar codes to improve the performance and the average number of iterations at the same time. Simulation results show that BP decoding can still achieve a better performance than the SC decoding in fading channels with the proposed termination.