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。
9,CC1f 6,1|y%(f function FF=frft_PXJ(N,alpha);
[!mjUsut* %matrix
Gc W}<g} % FF is the kernel matrix of fractional Fourier transform
#7h fEAk % \copyright: zjliu
di2=P)3 % Author's email:
zjliu2001@163.com FOi`TZ8 Ts=sqrt(2*pi/N); t=-(N-1)/2:(N-1)/2; t=t'; t=t*Ts;
nh )R variance=N/2/pi; HH=zeros(N); HH(:,1)=1; HH(:,2)=2*t;
V bOLTc for k=3:N;
Vz]=J;`Mz HH(:,k)=HH(:,k-1).*t*2-2*(k-2)*HH(:,k-2);
0pa^O$ ?p end
YWrY{6M HH(:,1)=1/sqrt(sqrt(variance))*HH(:,1).*exp(-t.*t/2);
GTl (i*
for k=2:N;
-<]_:Kf{;& HH(:,k)=exp(-t.*t/2).*HH(:,k)/sqrt(2.^(k-1)*...
%)Dd{|c factorial(k-1)*sqrt(variance));
d|RmU/) end
ZS]f+}0/} if mod(N,2)==1;
bU`yymf{L W=0:N-1; k=exp(-i*alpha*W); D=diag(k);
uTGvXKL7 else
3G|fo4g W=0:N-2; W=cat(2,W,[N]); k=exp(-i*alpha*W); D=diag(k);
#/<Y!qV& end
4CT9-2UC FF=Ts*HH*D*HH'*2;
JSK5x(GlH % Reference:
4ZpF1Zc4B % by 平先军.一种新的分数阶傅立叶变换快速算法.电子学报.
Zb;$ZUWQX % 2001(3),Vol.29:406-408.
