Optimization of ldpc codes used in cooperative relay systems: Case of mobile telephony

Abstract

This paper analyzes the Soft Information Relaying (SIR) for LDPC (Low Density Parity Check) codes in cellular networks. We propose a new way to generate soft parity bits at the relay. This generation of soft parity bits will be done in two steps and will be made to the Cholesky decomposition for one of the submatrices of the global matrix implemented at the destination. In addition to this generation of two-step, we offer an efficient way/manner to compute the logarithms of the Likelihood Ratio (LLR) to the destination. Simulation results show that this technique has advantages over some previous work.