%% =========================================================
%  Data
% =========================================================
X = single(raw_DPW.Data);
X = X(:,:,1:end); % first DPW useless (zeroed)

%% =========================================================
%  Parameters
% =========================================================
Fs = 512e6;        % Sampling rate (Hz)
N  = 512;          % Frame size

% Your data variable (rename if needed)
% Expected size: [512 x 4 x 8]
% X(frameSamples, frameIndex, timeIndex)
% Example: X = your_workspace_variable;

[nSamples, nFrames, nTime] = size(X);

%% =========================================================
%  FFT Computation
% =========================================================
FFT_all = zeros(N, nFrames*nTime);

idx = 1;

for t = 1:nTime
    for f = 1:nFrames

        x = X(:, f, t);

        % Optional window (uncomment if needed)
        % w = hann(N);
        % x = x .* w;

        Xf = fftshift(fft(x));
        FFT_all(:, idx) = abs(Xf);

        idx = idx + 1;
    end
end

%% =========================================================
%  Axes
% =========================================================
f_axis = (-N/2 : N/2-1) * (Fs/N) / 1e6; % MHz
t_axis = 1:(nFrames*nTime);               % frame index

%% =========================================================
%  Spectrogram-like view (BEST)
% =========================================================
figure;
surf(t_axis, f_axis, 20*log10(FFT_all + 1e-12), 'EdgeColor', 'none');
view(2);
axis tight;

xlabel('Frame index');
ylabel('Frequency (MHz)');
title('FFT over time (per frame)');
colorbar;

%% =========================================================
%  3D Visualization (optional)
% =========================================================
figure;
surf(t_axis, f_axis, FFT_all, 'EdgeColor', 'none');
xlabel('Frame index');
ylabel('Frequency (MHz)');
zlabel('Magnitude');
title('3D FFT evolution');

%% =========================================================
%  Single frame debug (optional)
% =========================================================
figure;
x_dbg = X(:,end,end);
Xf_dbg = fftshift(fft(x_dbg));

plot(f_axis, 20*log10(abs(Xf_dbg)+1e-12));
grid on;

xlabel('Frequency (MHz)');
ylabel('Magnitude (dB)');
title('Single Frame FFT');