On the photon counting error probability and its application in optical wireless communications.

We present an efficient approach for the probability of error (PER) of photon counting statistics in a pre-amplified optical receiver. Our approach enables a fast and highly accurate calculation of the instantaneous PER, as well as the average PER in optical wireless communications. By utilizing the proposed approximation, we assess the performance of an equal gain combiner (EGC) and a selection combiner (SC) in negative-exponential and γ-γ fading. The results show that the EGC provides a significant link gain under all fading conditions, while the SC is only viable in strong turbulence.