A novel low complexity detector for MIMO system

We propose a space alternating generalized expectation-maximization (SAGE) aided List-BLAST detection scheme, which can achieve performance close to that of the maximum-likelihood detector with low computational complexity. The SAGE algorithm searches for the ML solution iteratively by resolving the interference among signals from different transmit antennas. To improve the probability of convergence to the ML solution, multiple initial points are used. The List-BLAST algorithm, which exhausts the constellation points in the first layers of a BLAST detection scheme, is shown to be an excellent way to generate initial points. The complexity of the proposed detection scheme is compared with that of the sphere detection scheme and it is shown to have a number of implementation advantages.