Читать книгу Inverse Synthetic Aperture Radar Imaging With MATLAB Algorithms - Caner Ozdemir - Страница 48

%-------------------------------------------------------- % This code can be used to generate Figure 1.3 %-------------------------------------------------------- % This file requires the following files to be present in the same % directory: % % prince.wav % matplot.m clear all close all % Read the sound signal "prince.wav" [y,Fs] = audioread('prince.wav'); sound(y,Fs); N = length(y); t = 0:.8/(N-1):.8; %form time vector df = 1/max(t); f = 0:df:df*(length(t)-1); % TIME FREQUENCY PLANE SIGNAL A=spectrogram(y,256,250,400,1e4); % Calculate the spectrogram matplot(t,f*1e-3, (abs(A)),30); % Display the signal in T-F domain colormap(1-gray); % Change the colormap to grayscale grid minor set(gca,'FontName', 'Arial', 'FontSize',12, 'FontWeight','Bold'); xlabel('time, s'); ylabel('Frequency, KHz'); title('\itsignal in time-frequency plane');