Low-Complexity Hybrid QRD-MCMC MIMO Detection

In this paper, the authors propose a novel hybrid QRDMCMC MIMO detector that combines the features of a QRD-M detector and a Markov Chain Monte Carlo (MCMC) detector. The QRD-M algorithm is applied first to obtain initial estimates of the transmitted signal vector. Subsequently, the QRD-M estimate is used to initialize one of the Gibbs samplers for MCMC detection. The MCMC detection reduces the M parameter required by the QRD-M detector, while the QRD-M initialization effectively alleviates the well-known high-SNR problem in existing MCMC detectors. Performance of the QRD-M/MCMC detector is examined under both an idealized MIMO channel with perfect Channel Side Information (CSI) and a practical IEEE 802.16e MIMOOFDMA system with imperfect CSI.