互相关运算中的两个关键问题研究

Studies on Two Key Problems in Cross Correlation

互相关运算可以计算两个信号之间的时间差。但是,当两个信号的长度不相等时,如何得到正确的结果,以及如何提高互相关运算的时间分辨率是应用中的两个关键问题。本文通过理论分析和Matlab仿真进行研究。进行互相关运算的序列可以不相等,但为了得出正确结果,其长度之差必须小于一个周期。为了提高时间的分辨率,应该对互相关的结果进行插值。

Cross correlation can calculate the delay time between two signals.There are two key problems in applications of this correlation.One is how to obtain the right result when the lengths of two signals are not equal,and the other is how to improve the time resolution of cross correlation,which is not introduced in textbooks.This paper studies the problems with both theoretical analysis and Matlab simulations.It is permissible that cross correlation can be performed for two signals with different length,but in order to obtain the right result the length difference of two signals must be short than one period.It can improve time resolution of cross correlation that interpolation algorithms are adopted after cross correlation finished.