Study On Optical Heterodyne Detection In Coherent Opaticpael Rctoumrme Lunaidcaatrion

Coherent optical communication has the advantages of a high sensitivity, a long relay distance, good wavelength selectivity and a large communication capacity; it also supports multiple modulation modes. It would be a potential choice as laser communication technology developed in the future and has been studied extensively in recent years.As a key technology in coherent optical communication, optical heterodyne detection is studied in this thesis. The principle and advantages of optical heterodyne detection have been introduced. The polarization and wave-vector alignment and wave-front matching conditions for the maximum heterodyne signal have been analyzed.The definition and meaning of optical heterodyne efficiency have been introduced. The effect of wave-vector misalignment between signal and local oscillator on heterodyne efficiency is numerically calculated and stimulated using MATLAB, and the experimental result is also given. The influence of the wave-front mismatching, caused by the receiver optics, on the heterodyne efficiency is analyzed, and an improved receiver scheme is proposed.