The Circuit System Research Of Phase Laser Range Finder For No Cooperative Target

The application of laser measuring in many fields is increasing due to it's characteristic of needn't contact and high precision. Pulse laser rang finders are most used to measure long distance, and there are many products of this kind of range finder in the homeland. Phase range finders are more suitable to measuring short distance with high precise because digital phase detector of high frequency replace analog phase detector before, the phase laser range finder which has no cooperative target is very convenient, this kind of products are uncommon in the homeland, they have fine application prospect. This paper mainly introduce advanced research and realization of circuit system based on range finder.This system has three pivotal parts including realization of mixer, digital phase detector and anti-noise detecting weak signal. Our system successful realizes signal mixing by adopting high precision analog mixer and filter of nicer capability. The part of digital phase detection adopts Complex Programmable Logic Device, we adopt the series of MAX7000 produced by the company of Altera and this kind of CPLD can realize take counting of with high frequency of several hundreds HZ. The reception of our system adopts an ultra-low bias current monolithic operational amplifier and a band-pass filter which the value of Q can be set very high in order to filter noise. The whole system including processing of measure result and display is controlled by Single Chip Micyoco.This part of circuit in this phase rang finder system which has no cooperative targetfg is constructed based on the scheme depicted in our paper's main work. We find the circuit can realize the function of signal processing successfully by experiment and relevant results are gave in our paper. Some suggestion and improved method aim at each deficiency of three aspects including equipment choice , measure theory and dispose method in this system are gave in the end of this paper.