Obtain the phase difference between the two columns of signals based on the waveform data stored in the oscilloscope (MATLAB source code)

Purpose

The waveform displayed by the oscilloscope is as follows, and the phase difference between the two columns of signals needs to be obtained through MATLAB processing.

step

Insert the USB flash drive into the oscilloscope and store the signal sequence. Read this .CSV signal sequence file in MATLAB and process it to obtain the phase difference. code show as below:

clear all

close all

%Read data

t=xlsread('A2.CSV','A2','A1:A500');%Read time series

x=xlsread('A2.CSV','A2','B1:B500');%Read reference signal

x1=xlsread('A2.CSV','A2','C1:C500');%Read the signal to be measured

subplot 211;

plot(t,x,'b-');hold on;

plot(t,x1,'r--');grid;

legend('Reference','Signal');title('Origin');

%Data normalization

m1=(max(x)+min(x))/2;

m2=(max(x1)+min(x1))/2;

x=(x-m1)/max(x);   

x1=(x1-m2)/max(x1);

subplot 212;

index=find(x==0);

plot(t,x,'b-');hold on;

plot(t,x1,'k--');grid;

hold on;

legend('Reference','Signal');title('Normalization');

num=500; %number of data

l=0:1:num;

x=x;

y=x1;

Ix=sum(x.^2)/num;

Iy=sum(y.^2)/num;

Ixy=sum(x.*y)/num;

c=180*acos(Ixy/(Ix*Iy)^0.5)/pi; %Calculate phase difference

%disp(['Phase difference is',num2str(c), 'degree']);

output = sprintf('Phase difference is %f degrees', c);

output

result