On the eigenvalue distribution of smart-antenna arrays in wireless communication systems

The recent development of communication theory and smart-antenna techniques such as space-time coding (STC), which exchange efficiency for complexity, has intensified the interest in a general theory of multiple-antenna communication. These techniques use parallel channels to increase the capacity of wireless systems. The parallel channels are formed either in a natural way, due to radiowave propagation (receiving diversity, RD, RAKE), or in an artificial way, due to appropriate pre-processing and coding (transmitting diversity, TD, STC), or in both ways (multiple-input multiple-output, MIMO, systems, STC, BLAST). The demand for ubiquitous, heterogeneous, and sophisticated wireless systems has led to the need for a better understanding of fundamental issues in space-time communication theory, and their implications for the design of reliable, high-bandwidth and high-speed wireless communications. The authors discuss the issue of eigenvalue distribution for antenna arrays. The present article provides an approach that should be useful in simulations, analysis, and design of smart-antenna wireless systems. The results show that this parameter of the spatial channel has an important rcHe to play in analyzing the performance of antenna arrays in wireless systems.