yanminfu.m

概率的功率

nc=netcdf('19931107_135603_starea.cdf')
ipixinfo(nc)
[I,Q,meanIQ,stdIQ,inbal] = ipixload(nc,'hh',4,'auto');
figure(1),plot(I);
i=I(1:6000);figure(2),plot(i);
figure(3),histfit(i);
dfittool;pause;%拟合t分布
figure(4),histfit(abs(i));
dfittool;pause;%拟合weibull
%功率谱,对比几种方法采用改进的Welch法
Fs=1000; 
n=0:1/Fs:1; 
nfft=1024; 
window1=hamming(100); %海明窗 
noverlap=20; %数据无重叠 
range='half'; %频率间隔为[0 Fs/2]，只计算一半的频率 
[P,f]=pwelch(I,window1,noverlap,nfft,Fs,range); 
X=10*log10(P); 
figure(5),plot(f,X); 
pause;