%----------------------------------------------------------------------%
%%%%%%%%%%%%%classical?spectrum?estimation%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%Liudan%%%%%%%%%%%
%%%2010-12-11%%%%%%%%

clear?all
close?all
clc
fs=1000;
Ts=1/fs;
n=1024;
t=[0:1:n-1]*Ts;
%%%%%%%%%%周期圖法測頻精度仿真，改變信號(hào)的長度%%%%%%%%%%%%%%%%%%%%%%%%
fc1=150;
fc2=150.1;
fc3=150.015;
snr=0;
sn=10.^（snr/10）;
wc1=50*2/fs;
wc2=450*2/fs;
w=[wc1?wc2];
h=fir1（128w）;
n0=randn（1n）;
n1=conv（n0h）;
n1=n1（128/2+1:end-128/2）;
std=var（n1）;
x=sin（2*pi*fc1*t）+sin（2*pi*fc2*t）+sin（2*pi*fc3*t）;
n2=sqrt（3/（2*sn*std））*n1;
n3=fft（n21024）;
f=[0:511]*fs/1024;
figureplot（fn3（1:512））;
xlabel（‘頻率/Hz‘）;
title（‘200Hz帶限噪聲‘）;
y=x+n2;
Nfft1=1024;
Sw1=fft（yNfft1）;
A1=abs（Sw1）.^2/Nfft1;
%?A1=10*log10（A1）;
f2=fs*[0:Nfft1/2]/Nfft1;
%?figureplot（f2A1（1:1+Nfft1/2））;
%?xlabel（‘頻率/Hz‘）;
%?ylabel（‘功率譜‘）;
%?title（‘1024點(diǎn)信號(hào)長度周期圖法測頻精度分析‘）;
%?%?%%%%%%%%%周期圖法頻譜分辨率的仿真，改變矩形窗函數(shù)的長度%%%%%%%%%%%%%%%%%%%
fc4=300;
fc5=160;
fc6=350;
fc8=400;
fc7=420;
x1=sin（2*pi*fc7*t）+sin（2*pi*fc4*t）+sin（2*pi*fc1*t）+sin（2*pi*fc8*t）+sin（2*pi*fc6*t）+sin（2*pi*fc5*t）;
x1=2*sin（2*pi*fc1*t）+2.^0.5*sin（2*pi*fc5*t）;
Nfft0=1024*1024;
x12=fft（x1Nfft0）;
f2=fs*[0:Nfft0/2]/Nfft0;
x12=abs（x12）;
%?%?figureplot（f2x12（1:1+Nfft0/2））;
%?%?xlabel（‘頻率/Hz‘）;
%?%?ylabel（‘頻譜‘）;
%?%?title（‘信號(hào)的fft‘）;
n22=sqrt（3/（sn*std））*n1;
y1=x1+n22;
%?y1=x1;
%?window1=rectwin（1024）‘;
%?window1=[window1?zeros（1length（t）-length（window1））];
%?y11=y1.*window1;
%?Nfft2=1024;
%?Sw2=fft（y11Nfft2）;
%?A2=abs（Sw2）.^2/Nfft2;
%?A2=10*log10（A2）;
%?f22=fs*[0:Nfft2/2]/Nfft2;
%?figureplot（f22A2（1:1+Nfft2/2））;
%?xlabel（‘頻率/Hz‘）;
%?ylabel（‘功率譜/dB‘）;
%?title（‘512點(diǎn)矩形窗周期圖法‘）;
%?%?%%%%%%%%%%%%%周期圖法改變窗的類型以后的仿真%%%%%%%%%%
window2=rectwin（256）‘;
window2=[window2?zeros（1length（x）-length（window2））];
y11=y1.*window2;
Nfft2=1024*8;
Sw2=fft（y11Nfft2）;
A2=abs（Sw2）.^2/Nfft2;
A2=10*log10（A2）;
f22=fs*（0:Nfft2/2）/Nfft2;
figureplot（f22A2（1:Nfft2/2+1））;
xlabel（‘頻率/Hz‘）;
ylabel（‘功率譜/dB‘）;
title（‘矩形窗周期圖法‘）;
window3=bartlett（256）‘;
window3=[window3?zeros（1length（x）-length（window3））];
y11=y1.*window3;
Nfft2=1024*8;
Sw2=fft（y11Nfft2）;
A2=abs（Sw2）.^2/Nfft2;
A2=10*log10（A2）;
f22=fs*（0:Nfft2/2）/Nfft2;
figureplot（f22A2（1:Nfft2/2+1））;
xlabel（‘頻率/Hz‘）;
ylabel（‘功率譜/dB‘）;
title（‘bartlett窗周期圖法‘）;
window4=hamming（256）‘;
window4=[window4?zeros（1length（x）-length（window4））];
y11=y1.*window4;
Nfft2=1024*8;
Sw2=fft（y11Nfft2）;
A2=abs（Sw2）.^2/Nfft2;
A2=10*log10（A2）;
f22=fs*（0:Nfft2/2）/Nfft2;
figureplot（f22A2（1:Nfft2/2+1））;
xlabel（‘頻率/Hz‘）;
ylabel（‘功率譜/dB‘）;
title（‘hamming窗周期圖法‘）;
window5=hann（256）‘;
window5=[window5?zeros（1length（x）-length（window5））];
y11=y1.*window5;
Nfft2=1024*8;
Sw2=fft（y11Nfft2）;
A2=abs（Sw2）.^2/Nfft2;
A2=10*log10（A2）;
f22=fs*（0:Nfft2/2）/Nfft2;
figureplot（f22A2（1:Nfft2/2+1））;
xlabel（‘頻率/Hz‘）;
ylabel（‘功率譜dB‘）;
title（‘hann窗周期圖法‘）;
window6=blackman（256）‘;
window6=[window6?zeros（1length（x）-leng

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

?????文件???????3830??2010-12-16?19:23??現(xiàn)代譜估計(jì)?matlab程序\classicalestimation.asv

?????文件???????3830??2010-12-16?19:23??現(xiàn)代譜估計(jì)?matlab程序\classicalestimation.m

?????文件???????2735??2010-12-16?09:26??現(xiàn)代譜估計(jì)?matlab程序\classicalimprovement.m

?????文件???????1415??2010-12-14?19:41??現(xiàn)代譜估計(jì)?matlab程序\LD.m

?????文件???????1390??2010-12-14?13:56??現(xiàn)代譜估計(jì)?matlab程序\modemspetrumestimation.m

?????文件???????1124??2010-12-14?13:33??現(xiàn)代譜估計(jì)?matlab程序\modernspetrumestimation.m

?????目錄??????????0??2012-11-12?21:44??現(xiàn)代譜估計(jì)?matlab程序

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

????????????????14324????????????????????7