Diversity vs. adaptivity in multiple antenna systems

An information theoretic analysis of multiple antenna systems shows that the possible gain due to transmitter-sided channel knowledge is usually small for uncorrelated fading. However, it is not obvious how these results translate to real-world transmission strategies. Thus, in this paper the error performance of adaptive bit and power loading with perfect channel state information is compared to that of high-rate multistratum space-time codes relying only on transmit diversity. We demonstrate that the latter may even outperform the adaptive scheme if discrete rate constraints are taken into account.