结合CPLD测时的改进互相关算法在红外测速系统中的应用  

Research on the Application of Improved Cross Correlation Algorithm in Combined with CPLD Time Measurement in Infrared Velocity Measurement System

作　　者：韩亚秋 贾云飞[1] HAN Yaqiu JIA Yunfei(College of Mechanical Engineering, Nanjing University of Science and Technology, Jiangsu 210094, China)

机构地区：[1]南京理工大学机械工程学院,江苏南京210094

出　　处：《测试技术学报》2017年第1期29-33,共5页Journal of Test and Measurement Technology

摘　　要：为了解决直接采用传统互相关算法计算炮弹过靶时间差计算量大而不利于实时测量的问题,提出了一种结合CPLD的改进的互相关算法计算炮弹穿过两靶的时间差的方法.在分析炮弹穿过光幕时信号变化过程的基础上,设计CPLD测时模块测出弹丸过靶的时间差的估计值,根据CPLD测时结果筛选出参与互相关测时的相应时间段的信号,再进行互相关分析从而得出炮弹过靶时间差,计算出速度.最后通过MATLAB对仿真信号进行分析,表明采用改进的互相关算法不仅具有较少的计算量且有较高的精度.Thetraditional cross-correlation algorithm has a large amount of computation in calculating time difference of projectile passing through two targets,it is not conducive to real-time measurement.In order to solve the problem,an improved cross correlation algorithm combinedwith CPLD time measurement was proposed to calculate the time difference.Based on the analysis of thesignal changes of the projectile passing through the targets,the estimated value of the time difference was measured by the CPLD test module.It was proposed that the cross correlation analysis the effective signals after screening based on the the estimated valueto obtain the time difference of the projectile,and then calculating speed.Finally,through the analysis of the MATLAB simulation signal,it shows that the improved algorithm has less computation and higher precision.

关 键 词：CPLD测时 互相关算法 MATLAB仿真 红外测速系统 实时测量 

分 类 号：TH89[机械工程—仪器科学与技术]