基于FPGA技术的激光测距系统研究

【作者】 刘文；

【导师】 程翔；

【作者基本信息】 南京理工大学 ， 机械电子工程， 2007， 硕士

【摘要】 本文的研究内容是在激光测距项目基础上进行的，分析了各种激光测距方法的利弊，最终选用脉冲激光测距的实现方式，并且对脉冲激光测距系统做了深入研究。本文设计了以FPGA为核心的信号处理模块，实现了对激光信号的编码和译码、对激光发射控制时钟的分频、和内部PLL倍频实现内部高频计时时钟等，提高了系统的精度和稳定性。使用并行脉冲计数法，提高了计时精度，分析了可能产生误差的原因，并且对结果做了相应的修正，减小了激光测距系统的误差。并且制定了四种工作模式，可以根据不同的实际环境选择相应的测距模式，以达到最好的测量效果。在接收方面突破以往普通的被动接收方式，提出了利用窗函数接收回波的主动接收方式，结合窄带滤光片的滤光效果，提高了系统的抗干扰性能。从课题要求出发，本激光测距系统实现了体积小、功耗低的特点，测量距离相对较近(0.5-50米)，属于近距测量系统。更多还原

【Abstract】 The essay is based on the project of LRF (Laser Range Finder). It describes the meritand demerit of every class of LRF. EventUally I choose the way of using the laser-pulse tohave the range-measurement. I work hard on this measurement comprehensively.The result of this essay is to design the digital signal processor based on FPGA, tocode and decode the laser signal, to scale down the clock of launching part of the lasersystem and to use the PLL in the FPGA to make the frequency multiplication and so on.These make the system more stable and accurate. Using the parallel counter to count thepulse of the laser can increase the precision of the system. The essay considered manyreasons which may cause the inaccuracy. Amending these make the system more accurate.It has four patterns which will be used in different environment to make the gauge morereliable.In the receiving part of the system we receive the backward wave of laser using thewindow function in an active way. Usually the designer will receive the backward wave oflaser directly in a passive way. Using the spectral filter in this part can increase the noiseimmunity of system. The system has characteristics of small volume and low power andcan use in the range of 0.5-50 meters. It can be divided into the category of the short-rangeLaser Range Finder.更多还原