Photocounting Receiver Performance for Detection of Multimode Laser or Scattered Radiation

Photocounting distributions, the decision threshold, and the probability of error are obtained for a binary optical communication system in which both the signal and background radiation are Gaussian processes. This would be the case, for example, when the radiation source is a nonlocked multimode laser or when the received radiation is scattered from a satellite. Dark current is considered. The results indicate that when possible, counting times should be adjusted to be large in comparison with the background radiation coherence time, and optical amplification before detection should be employed.