A real-time optical correlator based on the principle of one-bit correlation, often used to facilitate the construction of real-time digital signal processors, is shown to have a greater immunity to mechanical noise than a comparable analog optical correlator. One-bit quantization also avoids some of the difficulties encountered with nonlinear light modulators. The one-bit optical correlator was studied by means of a computer simulation and an experimental system. Application of the technique to a multichannel correlator is discussed.
G. J. M. Aitken and D. R. Carter, "One-Bit Optical Correlator," Appl. Opt. 12, 1917-1921 (1973)