Polar Codes Construction for Fading Channels

Abstract

In this paper, we investigate the polar coding for fading channels, in which due to the limitation of practical channel estimation methods, some estimation below the limit is unreliable at the receiver. To mitigate the mischief of unreliable observations, the log-likelihood ratio (LLR) of the unreliable estimates is initialized with 0. The fading channels with unreliable estimations are modeled as a set of independent binary erasure channel (BEC) and the other channels with reliable estimations are modeled as a set of independent additive white Gaussian noise (AWGN) channels. We analyze the characteristics of these modeled channels and then propose a polar code construction scheme. Simulation results show that, the proposed coding scheme provides about 0.5dB gain at BER of 10–4 with respect to standard polar code on the fading channel.