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求平方根升余弦滤波器系数的程序

%calculate RCF coefficient
%我共享一下原来用MATLAB里面自己写的求平方根升余弦滤波器系数的程序。
clear
clc
alpha=0.4;
fs=409600;
fb=fs/4;
Ts=1/fs;
Tb=1/fb;
M=fs/fb;
W=6;
N=M*W+1;
L=(N-1)/2;

for n=1:1:N
nT=(n-1-L)*Ts/Tb;

if nT==0 
h(n)=(1-alpha)+4*alpha/pi; 
elseif (1-(4*alpha*nT)^2)==0 
h(n)=(pi*(1-alpha)*sin(pi*(1-alpha)*nT)+4*alpha*cos(pi*(1+alpha)*nT)-4*alpha*nT*(1+alpha)*sin(pi*(1+alpha)*nT))/(-32*pi*(alpha*nT)^2);
else
h(n)=(sin(pi*(1-alpha)*nT)+4*alpha*nT*cos(pi*(1+alpha)*nT))/(pi*nT*(1-(4*alpha*nT)^2));
end;
end;

b=rcosine(fb,fs,'fir/sqrt',alpha);
figure;
plot(-(length(b)-1)/2:1: (length(b)-1)/2,b,'bo-'); hold on 
plot(-(N-1)/2:1: (N-1)/2,h,'r+:'); 
xlabel('t/T');ylabel('h(t),b(t)');