Performance of Combined Constellation Rearrangement and Space-Time Block Coding Scheme for Multi-Level Modulation

In this paper, we present a combined constellation rearrangement and space-time block code scheme which is bandwidth- efficient and power-efficient and suitable for improving the performance of linear multi-level modulation schemes over multiple antenna transmission. Orthogonal transmit diversity with optimum signal combining can take full advantage of fading multi-path channels but for such a scheme the bandwidth efficiency decreases proportionally with the number of transmit branches. It will be shown that using different signal mapping constellations for each transmit branch improves the system performance. While keeping the same rate and complexity, both analytical and simulation results show a significant improvement of the system performance.