一种基于多重互相关的相位差测量新方法

本文研究了一种新的相位差测量原理,利用正弦信号的特性,直接对两路同频的正弦信号进行互相关运算,得到两路信号的互相关函数,同时保存两路信号的相位差信息,并多次对两路互相关函数进行互相关运算得到多重互相关函数,再利用相关原理对两路信号的多重互相关函数进行求解相位差信息。同时讨论了AD量化位数,信噪比,采样点数,谐波含量对本文算法的影响,实验结果表明本文算法能有效的提取两路同频正弦信号的相位差信息,算法简单,物理意义明确,具有一定的应用价值。特别适合与低信噪比或负信噪比下高精度的测量,并有很高的测量精度。

Phase Difference Measurement of Sinusoidal Signal based on Multi-layer Cross-correlation

A new method for phase difference measurement is introduced in this paper.Because the sinusoidal signal has a particular trait,do cross correlation to the two signals to get cross correlation function and keep the phase difference information.Multi-layer cross-correlation function is obtained by multi-layer cross correlation calculation to the cross-correlation function,and phase difference is obtained by using correlation theory.Length of sampled data,signal-noise ratio,number of ADC quantization bits and harmonic content which influence precision of phase difference measurement are particularly discussed and analyzed.Simulation results and conclusion are given.The simulations proves its feasibility and effectiveness to detect the phase difference.This method has many virtues such as simple theoretic deduction and explicit physical signification.It is especially fit for low signal-noise ratio condition or negative signal-noise ratio condition and it can get high resolution.