Performance evaluation of column-scaled LDPC codes under fading channel conditions

Abstract

Column scaling of LDPC codes is generally done to reduce the decoding complexity without degradation in bit error rate. It has been deduced that, the so constructed CS-LDPC codes had better performance than the existing regular and deterministic LDPC in terms of Bit Error Rate (BER). In this paper, ability of Column Scaled LDPC codes in reaching the best performance is evaluated for different fading channel conditions such as Additive White Gaussian Noise (AWGN), Rayleigh and Rician channels. Diagonal elements (that are not equal to zero) are distributed randomly in order to generate CS-LDPC. In Column Scaled Low density Parity Check codes, non binary parity check matrix, H is derived using Galios field or finite field polynomial and then non-binary H matrix is converted to binary H matrix. CS-LDPC codes have parity-check matrix that are composed of binary and diagonal matrix that eases implementation and analysis results shows that the CS-LDPC scheme improves Bit Error Rate and Frame Error Rate for AWGN and Rician channels and no significant improvement for Rayleigh channels.