# How to calculate FMCW Radar Chirp STFT?

I have received signal from FMCW Radar which is of the shape [128x64] = [Number of samples per chirp x Number of chirps per cycle] and i want to calculate the stft i am calculating it with stft command and for that using vectorized data.[1x8192]

fs = 1000e3;
win = blackman(64,'periodic');
[S,F,T] = stft(data,fs,'Window',win,'OverlapLength',60,'FFTLength',256);
S = abs(S);
imagesc(T,F,S);
colorbar;
xlabel('Time');
ylabel('Frequency');
zlabel('Amplitude');
title('Spectrogram');


From this i am getting the same plot for every cycle. Is this approach correct or do i have to calculate the stft separetely for every chirp? If my approach appraoch is correct what does this stft tells me? Data

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