clear all%窗口函数%n1=40;window=boxcar(n1);w1=window;figure(1);stem(w1);% 非平稳信号产生%fs=1000;a=0:1/fs:1;f0=0;f1=150;y1=chirp(a,f0,1,f1);x=y1(1:510);figure(2);plot(x);% 短时傅里叶变换%t=1:length(x);n=length(x);tfr,t,f=tfrstft(x,t,n,w1,0);contour(t,f,abs(tfr)clcclear all%窗口函数%n1=40;window=boxcar(n1);w1=window;figure(1);stem(w1);% 非平稳信号产生%fs=1000;a=0:1/fs:1;f0=0;f1=150;y1=chirp(a,f0,1,f1);x=y1(1:510);figure(2);plot(x);% 短时傅里叶变换%t=1:length(x);n=len
