10.7MHzFM中频信号的AD带通采样的MATLAB

代码如下：

% 10.7MHz FM中频信号的AD带通采样

% 设置采样率和采样时间
fs = 20e6;
T = 1/fs;

% 设置带宽和中心频率
B = 200e3;
fc = 10.7e6;

% 生成FM信号
t = 0:T:1-T;
kf = B/(2*pi);
m = 5*cos(2*pi*1e6*t);
s_FM = cos(2*pi*(fc + kf.*m).*t);

% 显示FM信号时域波形
figure(1)
plot(t, s_FM);
xlabel('Time (s)');
ylabel('Amplitude');
title('FM signal (time domain)');

% 计算AD带通滤波器参数
f1 = fc - B/2;
f2 = fc + B/2;
f3dB = B/2;
N = ceil(3.3*f3dB/fs);
h = fir1(N, [f1 f2]/(fs/2));

% 进行AD带通采样
s_ADC = s_FM(1:N:end);
s_filtered = filter(h, 1, s_ADC);

% 显示AD带通采样后的信号时域波形
figure(2)
plot(t(1:N:end), s_filtered);
xlabel('Time (s)');
ylabel('Amplitude');
title('AD sampled FM signal (time domain)');

运行结果如下图所示：