Study On Accurate Time Measuring Electric Circuit Of Imaging Laser Radar Based On APD Detector Array

Considering of the inherent advantage of laser technology, three-dimensional imaging laser radar has a stronger anti-jamming ability and can get higher-resolution image than traditional microwave radar. Meanwhile, laser radar is smaller and lighter.Therefore, in recent years, it received more and more attention in the field of radar technology. In previous years, because of foreign product and technology lock-in,three-dimensional imaging laser radar researchers in China didn’t pay enough attention to APD detector array. Most of them used techniques like single-beam scanning, ICCD or CMOS array image sensor gain modulation. Nowadays,improving ratio of signal and noise of gain modulation technique is still a difficult problem, so its image quality can’t reach that of APD array distance image.The imaging laser radar introduced in my graduation thesis takes the advantage of a high gain characteristic of APD linear array, and achieve three-dimensional image by pulse ranging and APD array linear scanning. This system uses 34 APDs to receive echo pulses, and measures each time interval of the 34 channels. Then it gets images by one axis scanning. My thesis analyzes in detail the working principle,electronic circuit design, experimental data and signal error of time measuring partial system, and gets a lot of valuable results and engineering experiences.This thesis mainly consists of five part. First, by describing the relevant technical status of three-dimensional imaging laser radar based on APD array, the research value of my subject is illuminated. Second, it elaborates the working principle and implementation method of the whole system and time measuring subsystem. Third, hardware circuit design stated in more detail. Fourth, software design of FPGA is introduced. Fifth, it roundly analyze the experient data.