Spot Position Detection Technology Based On Qd

Due to space laser communication systems have many smart points,such as broadband, high-speed, anti-interception capability, anti-interference ability and other advantages,which making it suit for space communication. After nearly30years of rapid development,the international nations have a deep studying in key technology of laser communication.As an information carrier, wireless laser communication technology,with its high bandwidth,high bit rate,high securit,low power consumption,have become the new direction of moedrn communication technology,which has good application prospects.Wireless laser communication links due to the narrow signalbeam,long transmission distance and other reasons.Thus,in wireless laser communication,we need establish a quick capture,targeting and tracking(Acquisiton,Pointing,and Tracking,referred APT)system to prevent disruption of the communication link,ensuring the entire communication process smoothly.In this paper, the object of study is capturing progress of the beacon of light of QD-based spot position detection technology. The design system includes a detector unit, a signal preprocessing unit, a data acquisition and transmission unit and the host computer monitoring unit, in the system,i optimize the preamplifier circuit, AD sampling circuit, using the classical four-quadrant position subtraction method solver. Meanwhile, we make a detailed simulation analysis of factors affecting spot position detection, and ultimately, in the existing laboratory conditions, the detection accuracy of this system is5urad, detection speed reaches20KHz.