Enhanced Soft Interference Cancellation Algorithm for V-BLAST Systems

In this paper, we investigate soft interference cancellation algorithms for vertical Bell Laboratories layered space- time (V-BLAST) systems. By using Gaussian-forcing technique and fast matrix computation, we first derive a simplified version of the conventional generalized probabilistic data association (GPDA) algorithm, called the fast soft interference cancellation (FSIC) algorithm, whose complexity is only cubic in the number of transmit/receive antennas. Then, based on the FSIC algorithm, we develop an enhanced soft interference cancellation (ESIC) algorithm by making use of the properties of MIMO channels. It is shown that with efficient iterative processing, the ESIC algorithm can achieve near-optimal performance in both uncoded systems and coded systems.