Application of smart antenna techniques in cellular mobile systems

The proliferating demand for cellular mobile radio services, and the relatively scarce resource of frequency spectrum provide the need for a fundamental improvement in spectrum efficiency of the new generation cellular mobile radio systems. The switched-beam smart antenna is more attractive when compared to the adaptive null steering, phased array smart antennas. In this paper, a theoretical approach is adopted to ascertain the performance improvement of multi-beam antennas, in which the fading and shadowing models are included. Numerical results of the outage probability under different values of protection ratios and co-channel reuse factors are provided. It is shown that a marked improvement in spectrum efficiency is achieved by reducing the co-channel interference level with adaptive multi-beam antennas employed at the base-stations.