A Laser Range Finder Based On Dds And Phase-shift

It is a searchment about hardware frame and parts of laser range finder which is miniature and fine precision, and the intention is making a higher precision in contactless measurement before installing equipment in a building.It is a chance for laser rang finder with more miniature and finer precision that the development of laser technology and microelectronics technology. In this study, bring a new design for laser range finder based on Direct Digital Frequency Synthesis technology and Phase-shift technology. The topics in it are, comparing the theory about pulse measurement to phase test, the advantage of phase test , and they are how to affect precision in this project. One of the emphases in this article is frequency synthesis by Direct Digital Frequency Synthesis technology. In these chapters, expatiating on the theory about Direct Digital Frequency Synthesis, how to select right chip, how to command DDS chip via program, and how to make the frequency control words. The other emphasis is phase-shift. It include that echo is broadened in time domain via mixer, and what the better phase detector is. And an amplitude modulation circuit for laser is also given in this study. In finally chapter, there are some experiences of system adjusting and test conclusions.