Four Quadrant Detector Applied Researrch In Space Laser Communication

The space laser communication system had broad prospects by the outstanding a dvantages of the high speed, wide broadband,anti-interference,anti-interception capabil ity and the miniaturization.And the communication system of high speed rate, miniaturi zation is one of the main trend of the development of laser communication system in the future.This paper was based on the the summary of the laser communication system’s development dynamic and trend at home and abroad,the fine tracking detector of P AT system in the laser communication system had been analyzed and studied in detail ed.This paper focused on the QD spot detection principle, spot detection accuracy,the detection performance and the method to improve detection accuracy.The follow-up pro cessing circuit of QD was designed on the basis of above mentioned to quickly reali ze the output light spot position signal.The experiment system that was designed had completed characteristics test of the QD device subdivision ability,sensitivity, spot size,background light and so on.The fine tracking test that was based on QD was finishe d under the condition of simulating air ship vibration.Investigation, analysis, test resu lts had the function of reference and guidance on the actual design of fine tracking s ystem based on QD.