High performance LDPC codes for high spectral efficiency
Résumé
Achieving high spectral efficiency is the key requirement of future wireless systems and mobile communications because it provides us a high quality for high data over a limited bandwidth. In order to achieve high spectral efficiency, channel coding and modulation are the key part. Basically, high spectral efficiency can be achieved when adopting a high order modulation and low code rate. Thus, the transmission with high spectral efficiency needs a high performance error correcting code. In this paper, a high performance binary LDPC code is introduced, and the performance of this code is evaluated . It is obtained by a parallel concatenation of two identical regular binary LDPC codes, separated by an interleaver through the turbo-code structure proposed by Berrou and others. Simulation results show that the performance of the proposed code, with higher order constellations (16-QAM, 64-QAM and 256-QAM) using Gray mapping, under Gaussian and Rayleigh channels has higher performance than a single LDPC code with the same block length. Also, we show that its performance can be improved with the increasing of two numbers of iterations: global iterations and/or iterations of binary LDPC codes, and the interleaver in the proposed code has a positive effect on the performance