function u = udftanal(x,g,M);

% Synopsis: u = udftanal(x,g,M).

% Maximally decimated uniform DFT analysis filter bank.

% Input parameters:

% x: the input sequence

% g: the FIR filter coefficients

% M: the decimation factor.

% Output parameters:

% u: a matrix whose rows are the output sequences.



% Part of software package for the book:

% A Course in Digital Signal Processing

% by Boaz Porat, John Wiley & Sons, 1997



lg = length(g); lp = floor((lg-1)/M) + 1;

p = reshape([reshape(g,1,lg),zeros(1,lp*M-lg)],M,lp);

lx = length(x); lu = floor((lx+M-2)/M) + 1;

x = [zeros(1,M-1),reshape(x,1,lx),zeros(1,M*lu-lx-M+1)];

x = flipud(reshape(x,M,lu)); % the decimated sequences

u = [];

for m = 1:M, u = [u; conv(x(m,:),p(m,:))]; end

u = ifft(u);