Effects of fog-haze random media on the short-range optical wireless communications link

A model for short-range optical wireless communication (OWC) link under fog-haze random media is presented based on the consideration of beam pointing error. The performance of OWC is analyzed in terms of received power, link margin, signal to noise ratio (SNR) and bit error rate (BER) with different track length, visibility of atmosphere, strength of the atmospheric turbulence, operating wavelength, emitting beam width, and variance of pointing error. It is found that we can ignore the impact of emitting beam width on the link margin, however, there is a optimizing emitting beam width wop for the SNR performance of the channel. The link margin and SNR decrease as the increasing of the track length and the turbulence strength. The link margin and SNR decrease as the meteorological conditions transform from clear, haze to heavy fog. The longer operating wavelength can increase the link margin and SNR. The pointing error caused by beam wander is the dominant factor and it seriously reduces the link margin and SNR, and increases the BER.