Design of miniaturized high precision laser azimuth detection system

摘要

Seeker technology is the core of laser semi-active guidance. At present, laser semi-active guidance weapons are mainly used for large caliber ammunition such as shells, bombs and missiles, while small caliber ammunition is rarely used. It is an important development direction of laser semi-active guidance weapons. In this paper, a miniaturized high-precision laser azimuth detection system for laser semi-active guidance seeker is designed. On the basis of existing laser plate active guidance seeker technology, the working principle of quadrant detector is analyzed. A quadrant detector with photosensitive diameter of 3.04mm and photosensitive area product of 2.52mm~2 is selected to design a high-precision calculation based on FPGA which is different from sum difference algorithm Law. According to the actual needs, the design index of the optical system is summarized. An optical system with an entrance pupil diameter of 8mm is designed. The optical system is evaluated and analyzed. The propagation characteristics of the laser in the atmosphere are analyzed. A variable gain amplifier circuit with a gain adjustment range of 24dB is designed. In order to improve the signal-to-noise ratio and anti-interference ability, the relevant detection circuit is designed. The experimental results show that the average absolute error of the system is 0.09° which meets the design requirements.