%% 3D Spectrogram Visualization
% Generate two seconds of a signal sampled at 10 kHz. Specify the instantaneous frequency of the signal as a triangular function of time.

fs = 10e3;
t = 0:1/fs:2;
x1 = vco(sawtooth(2*pi*t,0.5),[0.1 0.4]*fs,fs);

%
% Compute and plot the spectrogram of the signal. Use a Kaiser window of length 256 and shape parameter \beta=5. Specify 220 samples of section-to-section overlap and 512 DFT points. Plot the frequency on the y-axis. Use the default colormap and view.

spectrogram(x1,kaiser(256,5),220,512,fs,'yaxis')

%
% Change the view to display the spectrogram as a waterfall plot. Set the colormap to bone.

view(-45,65)
colormap bone

% Copyright 2015 The MathWorks, Inc.