A Study on Iterative Equalization with GaBP and Soft Successive Cancellation List Decoding in a Polar-Coded System

Abstract

We consider channel equalization with Gaussian Belief Propagation (GaBP) in a SISO polar coded single carrier transmission. GaBP requires soft values on reliability information for coded bits when the channel decoder is concatenated and iteratively decoded with GaBP. However, it is not so easy to generate the soft values of coded bits in general polar decoders. In this paper, we use soft successive cancellation list (SSCL) decoding for generating log-likelihood ratio (LLR) values of coded bits. In addition, we propose simpler methods to generate LLR values based on Log-domain SSCL decoding. The simulation results show that the SSCL decoding and its modified versions work well with GaBP and that the proposed method provides the same or better performance with less complex algorithm than that of SSCL decoding.