function [ output_args ] = showsin( input_args )%UNTITLED1 Summary of this function goes here%   Detailed explanation goes hereN=1024;f1=1000;fp=19000;fp2=38000;fs=152000;fx=-0.5:1/N:0.5-1/N;w=2*pi*f1/fs;wp=2*pi*fp/fs;wp2=2*pi*fp2/fs% 原始信號L=sin(w*[0:N-1]);M=L;ps=sin(wp*[0:N-1]);ps2=sin(wp2*[0:N-1]);% 調制信號S=L.*ps2+M;% 時域波形subplot(2,1,1);plot(S);title('沒有導頻');subplot(2,1,2);plot(S+0.1*ps)title('添加導頻');% plot(fftshift(abs(fft(S))));