Compute the STFT of the signal generated in Experiment 10.1 and compare it with the wavelet transform obtained in Experiment 10.1, using the MATLAB command spectrogram. Describe the differences in the representations of sinusoids and impulses in both cases.

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Experiment 10.1 Here, we see how wavelets can be used to analyze nonstationary signals. We start by generating a signal composed of a sequence of five sinusoids of different frequencies, corrupted by spikes. The beginning of each sinusoid is specified in the pos_sin variable and the corresponding period is defined in T_sin. For the spikes, their amplitude and time positions are as given by the amp_imp and pos_imp variables respectively. The MATLAB code to generate it is as follows: N = 2000; t = [0:N]; x = zeros (size (t)); pos sin [0 600 1080 1380 1680 2000]; T_sin [100 40 20 10 5]; for i 1:5, m = 1 + pos_sin(i); n = pos_sin (i+1); x(m:n) end; amp_imp = pos imp Timp for i = sin(2*pi*t (1:n-m+1)/T_sin(i)); [3 2 2 2.5 -2.5]; [200 372 1324 1343 1802]; [5 25 5 5 5 1; 1:5, m1+pos_imp (i); n = 1 + pos_imp (i)+fix (T_imp (i)/2); x(m:n) x (m:n) + amp_imp (i) *sin(2*pi*t (1:n-m+1)/T_imp (i)).^2; end;