Antenna gain for adaptive smart antenna systems

We study the antenna gain of an adaptive smart antenna system. The motivation for using the smart antenna systems is to increase the antenna gain and to extend the coverage of the system. Unlike traditional antennas whose gain is fixed, the gain of smart antenna systems depends on the signal processing algorithms used, the signal-to-noise ratio, and the data symbol size. We evaluate the antenna gain associated with several typical algorithms including an efficient one introduced in the paper. The effect of the signal-to-noise ratio and sample size on the antenna gain is also analyzed via statistical analysis as well as by computer simulations. Numerical results show that the adaptive smart antenna system can obtain close to the theoretical limit, i.e., 10 log₁₀ M[dB], where M is the number of antennas in a typical wireless communication environment