Abstract: A new combined maximum likelihood (ML) and decision feedback equalization (DFE) detection algorithm for the V-BLAST system is proposed based on nulling vector set searching. First the nulling vector set and corresponding signals of l levels are found with ML detection. Then the remnant signals of successive levels are gained level by level after removing the effect of first l levels. The analysis and simulation results show that, compared with the known combined ML and DFE detection based on the QR decomposition of the channel transmit matrix, this proposed algorithm can achieve the same detection performance but lower the computational complexity if the receive antennas number is smaller than the square of the maximum degree.

Key words: layered space-time architecture, maximum likelihood detection, decision feedback, nulling vector