Unitary Constellation Design with Application to Space-Time Coding

Recently unitary space-time modulation has been presented to give a solution to more reliable multiple antennas communications. Good-performing unitary constellations are required to be designed to fit into this system. Although the basic principle is well understood and certain criteria and their transformations for designing such constellations have been presented, we don’t have a general method to design goodperforming constellation for any number of transmit and receive antennas and for any transmission rate. In this paper, we design unitary constellations which have good diversity product in some specific situations and we analyze the asymptotic behavior of some special constellations. We describe a new design criterion for low SNR channel, also we present a mixed code scheme which features good performance unitary constellations. These constellations all come with efficient decoding algorithms.