是信號週期性還是不是？使用MATLAB功能可能嗎？

Question

簡要說明使用MATLAB功能

像isperiodic（信號）信號的（非）週期性的原因...

任何像這樣的事情嗎？

Answer 1

fft可以做到這一點：

Y = fft(signal); 
periodLength = 'second'; %or whatever units your signal was acquired in. 
N = length(Y); 
Y(1) = []; 
power = abs(Y(1:floor(N/2))).^2; 
nyquist = 1/2; 
freq = (1:floor(N/2))/floor(N/2)*nyquist; 
figure; 
plot(freq,power) 
grid on 
xlabel(['cycles/' periodLength]); 
title('Frequency plot'); 

，這給它作爲每個週期的週期數。

period = 1./freq; 
figure; 
plot(period,power) 
grid on 
ylabel('Power') 
xlabel(['Period (' periodLength 's/Cycle)']); 
title('Period Plot'); 

Answer 2

查找到的信號的autocorrelation概念，（XCORR函數在MATLAB）