An Improved QRD-M Algorithm in MIMO Communications

QR decomposition based M algorithm (QRD-M) is a type of maximum likelihood signal detecting (MLSD) scheme to provide a tradeoff detecting method between the system performance and complexity in multi-input multi-output (MIMO) communications. But for the conventional QRD-M algorithm, only one parameter, the maximum number of the survived branches, is used to make tradeoff, which cannot provide more valuable tradeoff options with better performance to complexity ratio. In this paper, an improved QRD-M algorithm with two independent parameters is proposed. It can provide more and better tradeoff options, which is proved through complexity analysis and numerical simulations.