Blocking losses on an optical communications link

Many photon-counting photo-detectors have the property that they become inoperative for some time after detection event. We say the detector is blocked during this time. Blocking produces losses when using the detector as a photon-counter to detect a communications signal. In this paper, we characterize blocking losses for single detectors and for arrays of detectors. For arrays, we discuss conditions under which the output may be approximated as a Poisson point process, and provide a simple approximation to the blocking loss. We show how to extend the analysis to arrays of non-uniformly illuminated arrays and provide numerical methods to accurately predict count rates for detectors with exponential recovery from the blocked state.