Laser Dynamic Target Real-time Ranging Study

Timely distance measurement for moving objects apart from 10 meter to 1000 meter is studied in this paper. Laser beam and its travel characters in the air, and elementary theory of lidar distance ranging are discussed. For the particularity of moving object, the relation between receiving light power and instance at certain accuracy is discussed with diffusion and collaborators. Because of the moving of target and the speedy changing of receiving light power, traditional phase distance measurement way is not adoptable again under the circumstances. A new way of distance measurement is introduced in this paper, it is similar to traditional measurement way, and has its origination. In the new measurement way, the rough measurement of the distance is realized by countering high frequency pulses filled in discriminable phase pulses. Discriminable phase pulses go through integral circuits, and then are sampled by Analogue Digital Converter (ADC), so the accurate measurement of the system is obtained by the sampling value. Automatic Gain Control (AGC) of APD is used to replace usual reducing light instrument. The digital circuit is realized by complex programmable logic device (CPLD), the system is controlled by MSP430F437PZ. By programming in IAR Embedded workbench and debugging with hardware system, the new measurement way is proved to be feasible.