% function b = fir_rrc(fa, T, N, alpha)
% Root Raised Cosine FIR-Filter

function b = fir_rrc(fa, T, N, alpha)

n = -(N-1)/2:1:(N-1)/2;
t = n/fa;

A = 4*alpha/(pi*sqrt(T))

nom = 4*alpha*cos((1+alpha)*pi*t/T) + T*sin((1-alpha)*pi*t/T);
denom = pi*sqrt(T)*(1 - (4*alpha*t/T).^2);

% Find zero elements
ze = find(abs(alpha*t/T) == 0.25)

%nom(ze) = sqrt(T)*(1 - alpha*(1 - (4/pi)));
%denom(ze) = 1;

b = nom./denom;