BER Performance Analysis of LDPC Codes for Min- Sum Decoding Algorithm

Low density parity check (LDPC) codes are adopted in many applications due to their Shannon limit approaching error correcting performance. In this paper, we analyze the Bit Error Ratio (BER) performance of LDPC codes with different codeword length and different number of iterations over Additive White Gaussian Noise (AWGN) channel. The encoding of LDPC codes is done with standard method and it is implemented using MATLAB. Codewords have been constructed for code rate 1/2. LDPC codes can be decoded using iterative decoding algorithm to improve the performance. Here, the min-sum decoding algorithm is implemented and desired simulation results were obtained using MATLAB. The min-sum algorithm is mathematically equivalent to the sum-product algorithm and it greatly reduces the computational complexity of sum-product algorithm. The simulation results show that higher the number of iterations, better the code's performance.