Simplified lattice decoding for orthogonal space-time codes

We present a lattice-decoding algorithm for a multiple antenna system. While the complexity of the maximum-likelihood (ML) algorithm is exponential both in the number of antennas and the rate, the complexity of our algorithm is polynomial in the number of antennas and the rate and has lower complexity than the method used in Tarokh et al. (1999). We also show that the performance of our lattice decoding is the same as the ML algorithm performance.