untitle3.m

来自「利用DFT分析模拟信号频谱,并附有实验报告说明和源码」· M 代码 · 共 16 行

N=50;
f1=50;
f2=120;
fs=300;
T=1/fs;
ws=2*pi*fs;
t=(0:N-1)*T;
f=sin(2*pi*f1*t)+sin(2*pi*f2*t)+randn(1,N);
wh=(hamming(N))';
f=f.*wh;
F=fftshift(fft(f,L));
w=(-ws/2+(0:L-1)*ws/L)/(2*pi);
plot(w,abs(F));
xlabel('w');
ylabel('x(t)的幅度谱')