Analysis of an array-based high-speed integrated optical receiver in a FSO USRP OFDM testbed

A new high-speed integrated wireless optical receiver with a large detection area is proposed. It is composed of a large number of identical optical receivers, each consisting of a high-speed photodiode, and a subsequent low-noise amplifier. The output signals of all receiver paths are combined by an adding circuit such that the signal-to-noise ratio (SNR) can be improved significantly. This paper first introduces the N array-based optical receiver circuit and simulation results in regard to its SNR. The results are experimentally verified with circuits consisting of N=1 and N=5 receiver paths in a free space optics (FSO) orthogonal frequency division multiplexing (OFDM) testbed to verify the results obtained by the theoretical approach.