Optimum order of angle diversity with equal-gain combining receivers for broad-band indoor optical wireless communications

Angle diversity is an effective technique to compensate for multipath temporal dispersion in a wireless infrared environment. Diversity is accomplished by using a multibranch receiver capable of resolving multipath. The goal of this paper is to illustrate the effect that the increasing diversity order of a receiver has on the performance of a link in a multispot-diffusing configuration with equal-gain combining outage probability based on probability of bit error is adopted as a performance measure. It is shown that there is an optimal number of branches, which minimizes outage probability. Increasing diversity order beyond this optimal number degrades the performance and increases the receiver complexity, cost, and susceptibility to any shadowing effects.