The Design And Experiment On Pulse-Phase Laser Rangefinder

Due to the advantages of laser, such as high directionality and brightness, laser ranging technology has a potential of massive application and bright future. In particular, it is the semiconductor laser that make it possible to make portable laser rangefinder of high precision. Laser rangfinder is becoming one of the main tools for short-distance ranging. Given these advantages, we illustrate the design scheme of a kind of pulse-phase laser rangefinder, and relevant experiment results in this article.Firstly, we choose the pulse-phase laser ranging method as a major principle to achieve a target of high precision, easy to implement, based on the comparision among some basic principles of laser rangefinder. The overall design is then break down to three main modules: signal transmition&receiving module; signal processing modules. Detailed information of the implementation of those modules is described in the article.Secondly, the principle of the circuit and receiving circuit is analysed in the article, and a Quasi - CW laser transmitter circuit and electro-optical circuits for high-frequency signal reception is got. Through debugging and performance testing, the transmitting and receiving circuits is determined.Next, the signal processing circuit is separated into module design. By analyzing the frequency mixer, a circuit to archive basic Analog Mixing is got. The phase discrimination process is decribed using VHDL hardware description language. And discrepancies of the phase of transmission and reception signals is compared by simulation.Finally, the results of transmitting and receiving circuit, and the simulation results of the signal processing circuit and the phasing circuit are analyzed in the thesis, finishing the design and simulation on a pulse-phase type laser rangefinder.