Noise Immunity of Signal Reception in the Optical Band with Discrete Polarization Modulation

An expression is obtained for the probability of incorrect reception of signals in the optical band with discrete polarization modulation; the quantum nature of the signals is taken into account. Reception is achieved with an ideal Zigert–Kotel'nikov receiver. Curves are drawn which permit an estimate of reception efficiency. When the signal-to-noise ratio increases without limit the probability of incorrect reception tends to the quantum limit. During transition from the quantum region to the classical region the probability of incorrect reception depends only on the signal-to-noise ratio and does not depend on the useful signal power.