Pulsed Diode Laser Ranging Circuit And System Design

With the increase of semi-laser's power and improvement of the fabricationtechnology, the research of rangefinder based on semi-laser is booming gradually,although laser range finding is the first application of military laser technology. Thedesired goals in the project are: distance＞1 km,precision＜1 m. This paper introduce thefundamental principle of pulse semi-laser rangefinder and headway of it. Together withthe actual project, the detail of principle and steps about system design is described.Then, the method of system simulation with computer is given. At the the same time,the key system parameters, such as laser peak power, rise edge, signal noise rate werederived. After analyzing several possible schemes, the author design and analysis thecircuits of a few parts of the rangefinder and simulating them in Saber Design software.As a result, the circuit of laser pulse transmitter, preamplifier of photoelectric receiverbased on APD, constant fraction discriminator and time-to-amplitude converter arecompleted. Differentiating from common semi-laser rangefinder, the multi-targetproblem is discussed. And the approach is based on MCU. At last, the result of rangefinding was display on screen by the video char generator.