Iterative Detection and Decoding Algorithms using LDPC Codes for MIMO Systems in Block-Fading Channels

摘要

We propose iterative detection and decoding (IDD) algorithms with Low-DensityParity-Check (LDPC) codes for Multiple Input Multiple Output (MIMO) systemsoperating in block-fading and fast Rayleigh fading channels. Soft-inputsoft-output minimum mean-square error receivers with successive interferencecancellation are considered. In particular, we devise a novel strategy toimprove the bit error rate (BER) performance of IDD schemes, which takes intoaccount the soft \textit{a posteriori} output of the decoder in a block-fadingchannel when Root-Check LDPC codes are used. A MIMO IDD receiver with softinformation processing that exploits the code structure and the behavior of thelog likelihood ratios is also developed. Moreover, we present a schedulingalgorithm for decoding LDPC codes in block-fading channels. Simulations showthat the proposed techniques result in significant gains in terms of BER forboth block-fading and fast-fading channels.