Unified design of linear space-time block codes

A number of space-time codes have been recently proposed for the quasi-static, flat-fading, multipleantenna wireless channel with coherent receiver. In this paper we will focus on design of space-time codes that are linear in the scalar input symbols. We provide design criteria that take into account both the error probability and the channel capacity. We consider the error probability via the union bound instead of the conventional pairwise error probability and provide conditions on unitary codes to minimize the union bound. Then we provide conditions on linear codes that maximize channel capacity, i.e. capacityefficient codes. Finally we provide design rules that optimize the error performance of capacity-efficient linear codes, and demonstrate performance improvements by means of simulations.