clc;?clear;
t0=-0.1;?t1=0.1;?%調(diào)制信號(hào)的時(shí)域范圍?
fs=1000;?ts=1/fs;?%采樣率
t=t0:ts:t1;
m=sinc（100*t）;?%調(diào)制信號(hào)fm=50;
fc=300;?%載頻
x=cos（2*pi*fc*t）;?%載波信號(hào)
kf=100;?%偏差常數(shù)
u=GetFMSignal（mt0t1tsfckf）;?%已調(diào)制信號(hào)
%畫調(diào)制信號(hào)和已調(diào)制信號(hào)的波形
subplot（321）;plot（tm）;title（‘基帶信號(hào)‘）;
subplot（322）;plot（tu）;title（‘已調(diào)制信號(hào)‘）;

df=0.25;?%FFT時(shí)的頻率分辨率
f=[0:df:df*（length（t）-1）]-fs/2;?%與t對(duì)應(yīng)的頻率向量
[Mm_newdf_new_m]=GetFFT（mt0t1tsdf）;
[Uu_newdf_new_u]=GetFFT（ut0t1tsdf）;
%FFT變換后，對(duì)兩個(gè)頻率向量重新賦值
f1=[0:df_new_m:df_new_m*（length（m_new）-1）]-fs/2;
f2=[0:df_new_u:df_new_u*（length（u_new）-1）]-fs/2;
subplot（323）;plot（f1abs（fftshift（M）））;xlabel（‘基帶信號(hào)頻譜‘）;
subplot（324）;plot（f2abs（fftshift（U）））;xlabel（‘已調(diào)制信號(hào)頻譜‘）;

phase=GetDEM（ut0t1tsfc）;?%解調(diào)，得到相角
phase_new=unwrap（phase）;?%對(duì)相角平滑處理
m_dem=1/（2*pi*kf）*diff（phase_new）;
m_dem_new=[m_dem0];?%求微分后少了一個(gè)點(diǎn)，補(bǔ)0
subplot（325）;plot（tm）;xlabel（‘原基帶信號(hào)‘）;
subplot（326）;plot（tm_dem_new）;xlabel（‘解調(diào)后基帶信號(hào)‘）;

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----

?????文件???????1077??2008-12-07?14:47??FM\FM.m

?????文件????????126??2008-12-07?14:48??FM\GetDEM.m

?????文件????????347??2008-12-07?14:49??FM\GetFFT.m

?????文件????????201??2008-12-07?09:50??FM\GetFMSignal.m

?????文件????????135??2008-12-07?14:13??FM\GetQuaSignal.m

?????文件????????143??2008-12-07?09:49??FM\m_INT.m

?????文件?????137592??2018-11-17?18:08??fm.docx

?????目錄??????????0??2008-12-12?18:30??FM

-----------?---------??----------?-----??----

???????????????139621????????????????????8