New simplified sum-product algorithm for low complexity LDPC decoding

Abstract

This paper proposes new simplified sum-product (SSP) decoding algorithm to improve BER performance for low-density parity-check codes. The proposed SSP algorithm can replace multiplications and divisions with additions and subtractions without extra computations. In addition, the proposed SSP algorithm can simplify both the ln[tanh(x)] and exp[tanh-1(x)] by using two quantization tables which can reduce tremendous computational complexity. Moreover, the simulation results show that the proposed SSP algorithm can improve about 0.3~0.8 dB of BER performance compared with the existing modified sum-product algorithm.