Impact of signal constellation expansion on the achievable diversity in quasistatic multiple-antenna channels

This paper studies the effect of signal constellation expansion on the achievable diversity of space-time codes in quasistatic multiple antenna channels. Signal constellation expansion can be obtained either by increasing the size of the constellation in the complex plane or by using multidimensional linear mappings. By means of two simple space-time code constructions, we provide a comparison of the two options with message passing decoding. We show that multidimensional expansion that inherently achieves full diversity, can be advantageous over complex plane expansion due to its intrinsic design flexibility.