Study On Optical Heterodyne Detection In Synthetic Aperture Ladar Technology

Synthetic Aperture Ladar (SAL) is a kind of imaging Ladar utilizing synthetic aperture technology to obtain high resolution images without large optics aperture. Compared with Synthetic Aperture Radar (SAR) using microwave as radiating source SAL has many advantages due to its shorter radioactive wavelength.As the key technique in Synthetic Aperture Ladar (SAL), optical heterodyne detection is studied in this thesis. The optical heterodyne experiment by use of a diode pumped solid-state laser has been made. In addition, several experiments are taking for detecting some diffuse reflection targets, and the clear results are received.By analyzing the characteristic of optical channel, it establishes a model of optical distribution on detector surface. Then, four major factors which influence the optical heterodyne efficiency are given. By comparing the optical heterodyne efficiency between the condition of exact matching and mismatch, also some experimental data, the corresponding solutions are given.