Get the frequencies at specific value of amplitude

Hello everyone, I want to split the signal using the Gabor transform and then taking the values of frequency against the maximum value of amplitude within each window. Thank you for helping me.

Answer 1

[Vinay]

Hii Abdul,

The Short-Time Fourier Transform (STFT) divides a longer signal into smaller segments of equal length and computes the Fourier transform separately for each segment. The frequency corresponding to the maximum amplitude within a specific window can be analyzed using the code provided below.

% Parameters
Fs = 22000; 
t = 0:1/Fs:1; 
windowLength = 256;
overlap = 128;

signal = sin(2*pi*50*t) + 0.5*randn(size(t)); % Signal with noise

% Short-Time Fourier Transform (STFT)
[S, F, T] = stft(signal, Fs, 'Window', hamming(windowLength), 'OverlapLength', overlap, 'FFTLength', windowLength);

% Initialize vector to hold frequencies
maxFreqs = zeros(size(T));

% Loop to find the frequency of maximum amplitude
for k = 1:length(T)
    [~, maxIdx] = max(abs(S(:, k)));
    
    % frequency of the maximum amplitude
    maxFreqs(k) = F(maxIdx);
end

% Display the results
disp('Frequencies of maximum amplitude in each window:');
disp(maxFreqs);

Kindly refer to the following documentation for “short time fourier transform”:

https://www.mathworks.com/help/signal/ref/stft.html

I hope this helps!

[Abdul Rahim]

Thank you for taking the time to read my question and answer it.