Simulation of Multipath Impulse Response for Indoor Wireless Optical Channels

We present a recursive method for evaluating the impulse response of an indoor free-space optical channel with Lambertian reflectors. The method, which accounts for multiple reflections of any order, enables accurate analysis of the effects of multipath dispersion on high-speed indoor optical communication. We present a simple algorithm for computer implementation of the technique. We present computer simulation results for both line-of-sight and diffuse transmitter configurations. In both cases we find that reflections of multiple order are a significant source of intersymbol interference. We also report experimental measurements of optical multipath, which help verify the accuracy of our simulations. Presented in part at IEEE Workshop on Wireless Local Area Networks, May 1991, Worcester, MA. This work was supported by T. J. Watson Research Center, Hawthorne, NY, and by the California State MICRO program.