Assessment of the influence of intensity of optical signal on the probability of erroneous data registration in a single-photon communication channel

When measuring low-power optical signals in single-photon communication channels, the receiving modules must ensure the minimum probability of erroneous data recording. In this regard, it is advisable to use photon counters. They are highly sensitive, but are characterized by data recording errors. The aim of the work was to determine the effect of intensity of optical signal on the probability of erroneous data recording in a single-photon communication channel with a receiving module based on a photon counter. Based on the results of experimental studies, the dependences of the probability of erroneous registration of binary symbols «0» P err 0 on the intensity of the optical signal J 0 , used to transmit these symbols for various supply voltages of the avalanche photodetector U, were obtained. It was found that with an increase of intensity of the optical signal, the dependences P err 0 ( J 0 ) first decrease, reaching their lowest value, and then increase. The performed assessment showed that the lowest probability of erroneous registration the binary symbols «0» for the investigated communication channel is equal to 17,56 • 10 -2 and corresponds to J 0 = 52,41 • 10 -2 rel. units and U = 52,54 V.