Spectrogram - How to divide signal ?

14 views (last 30 days)
RuiQi
RuiQi on 8 Apr 2016
Edited: Rick Rosson on 8 Apr 2016
Hello
I have a signal 120 seconds long with sampling frequency 1KHz. How do I compute the spectrogram with 120 time segments ? Each segment 1000 samples. The code below gives me t = 136 not 120
segments = 120;
windowsize = 1000;
nfft = 1000;
[S,F,T,P] = spectrogram(data,windowsize,segments,nfft,Fs);

Accepted Answer

Rick Rosson
Rick Rosson on 8 Apr 2016
Edited: Rick Rosson on 8 Apr 2016
The third input argument of spectrogram expects the number of samples to overlap each window, not the number of segments. Please try:
winSize = 1000;
overlap = 0;
fftSize = winSize;
[S,F,T,P] = spectrogram(data,winSize,overlap,fftSize,Fs);
It is common practice, however, to set the overlap to half of the window size:
overlap = floor(winSize/2);
but it is not required if you don't want it.
HTH.

More Answers (0)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by