Combined maximum likelihood and ordered successive interference cancellation grouped detection algorithm for multistream MIMO

The use of multiple antennas at the transmitter and receiver results in enormous capacity increase. As a space-time architecture, VBLAST has demonstrated very high spectral efficiency. The performance of the original detection algorithm for VBLAST (vertical Bell Laboratories layered space time), OSIC (ordered successive interference cancellation), is far from that of ML (maximum likelihood). Due to error propagation, the overall performance of OSIC is determined by the first stages to be decoded. We present two modified detection algorithms that aim at lessening the gap between the original VBLAST detection and ML detection. These schemes can achieve the desired trade-off between performance and complexity under a suitable parameter choice. With little increase in computational complexity, a high improvement in error performance over OSIC is achieved.