OPTICAL RECEIVER, OPTICAL RECEPTION METHOD AND OPTICAL COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an optical receiver R of optical CDMA capable of improving communication quality without recognizing information relating to other users. SOLUTION: Reception signals are inputted to an optical hard limiter 21 for turning the reception light of a size equal to or more than the signal strength of a desired user to the signal strength of the desired user and limiting the reception light smaller than the signal strength of the desired user to 0. Optical signals limited by the optical hard limiter 21 are correlated with the optical signals at the weight position of a spread code in a correlation device 23 and the correlated optical signals are inputted to a photodetector 24. Since the optical intensity of the reception signals is limited by the optical hard limiter 21, respective output signals from the photodetector 24 take one of two values. Based on the two values, likelihood judgment is performed in a coupling likelihood judgment device 25 and transmitted signals are demodulated.