Using ray tracing to evaluate smart antenna system performance for wireless communications

This paper motivates the use of electromagnetic ray tracing for the study of smart antennas in Space Division Multiple Access (SDMA) systems. Whereas past ray tracing studies applied to the study of wireless communications systems have been conducted at low spatial resolution for cell-site design, this study makes use of high resolution data so that fast fading effects could be observed. Uplink diversity gain and downlink signal to interference ratio data is simulated for several mobile user environments to gain insight into the fundamental performance limiting criteria of SDMA systems. Mobile environments were varied from several simple artificial urban environments to a simulation of downtown Austin, Texas. When applicable, all simulation results compare favorably with measurement data taken using the smart antenna testbed at the University of Texas at Austin.