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2008-12-02 10:26 |
实现分数傅立叶变换的matlab程序
转载一个实现分数傅立叶变换的matlab程序，作者信息在程序中有。 HRCnjem/v\
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function FF=frft_PXJ(N,alpha); ~g@}A
%matrix uA t{WDHm
% FF is the kernel matrix of fractional Fourier transform m G+=0Rn^
% \copyright: zjliu : Hu {MN\
% Author's email: zjliu2001@163.com } {&;\^i
Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
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variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t; Bob-qCBV
for k=3:N; mO8/eVws[M
HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2); <29K!
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end 5x,/p
HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2); <q I!Dj{
for k=2:N; H%}/O;C
HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*... $e uI
factorial(k-1)*sqrt(variance)); 'C>s YSL
end f'M([gn^_
if mod(N,2)==1; z'"Y+EWN
W=0:N-1; k=exp(-i*alpha*W); D=diag(k); Zdfh*MHMg
else Krl9O]H/[
W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k); kN#3HI]8
end (I+e@UUiL
FF=Ts*HH*D*HH'*2; *=T(ncR['
% Reference: NQvI=R-g
% by 平先军.一种新的分数阶傅立叶变换快速算法.电子学报. Ua=r24fy
% 2001(3),Vol.29:406-408.
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