A Brief Overview and Experimental Researches of Novel PL-log-MAP Turbo Decoding Algorithm

Abstract

In this article, we discuss the powerfull class of channel codes referred to as turbo codes. These error-correcting technique achieve excellent error-rate performance that can closely approach Shannon’s channel capacity limit. We commence with a brief discussion for MAP and log-MAP decoding algorithms. We work with proposed turbo decoding method referred as PL-log-MAP. The mathematical model is based on the piecewise linear approximation of the the correction term in the Jacobian logarithm. So complex functions ln(.) and exp(.) in the log-MAP algorithm can be estimated with high accuracy and lower computational complexity. The efficacy of the proposed approximation is investigated and demonstrated by applying it to digital communication system. We presented some numerical results and research experiments (simulation for estimation for bit error rate, images transmission). It is shown that the PL-log-MAP algorithm performance to have the closest performance to the original log-MAP.