function F = fracF_dpw(f,...
                       Achirp,...
                       H,...
                       Cchirp,...
                       Aa)
%#codegen
%% fracF_dpw  Fractional Fourier Transform for an entire DPW
%
%   F = fracF_dpw(f,Achirp,H,Cchirp,Aa)
%
%   Computes the Fractional Fourier Transform (FrFT) of all frames in a
%   Digital Processing Window (DPW) using a matrix-oriented implementation.
%
%   The algorithm follows the same chirp-convolution-chirp formulation as
%   fracF_cg(), but processes all DPW frames simultaneously. Each column of
%   the input matrix is treated as an independent frame, following the same
%   "columns are channels" convention used by DSP System Toolbox blocks.
%
%   Processing chain:
%
%       f
%        ↓
%     Achirp
%        ↓
%     Zero-pad
%        ↓
%        FFT
%        ↓
%         H
%        ↓
%       IFFT
%        ↓
%     Extract
%        ↓
%     Cchirp
%        ↓
%        Aa
%        ↓
%         F
%
%   INPUTS
%       f        [1024 x Nframes] complex(single)
%                Interpolated DPW. Each column corresponds to one frame.
%
%       Achirp   [1024 x 1] complex(single)
%                Pre-multiplication chirp (A chirp).
%
%       H        [2048 x 1] complex(single)
%                FFT of the convolution chirp (B chirp).
%
%       Cchirp   [512 x 1] complex(single)
%                Post-multiplication chirp (C chirp).
%
%       Aa       scalar complex(single)
%                FrFT amplitude factor (A_alpha).
%
%   OUTPUT
%       F        [512 x Nframes] complex(single)
%                FrFT result for all DPW frames.
%
%   Notes
%       - Input length is fixed at N = 1024 samples.
%       - Output length is N/2 = 512 samples.
%       - All DPW frames are processed simultaneously.
%       - Numerically equivalent to applying fracF_cg() independently to
%         each column of the input matrix.
%       - Intended for code generation and RFSoC PS deployment.
%
%   See also:
%       fracF_init
%       fracF_cg

%% Fixed transform dimensions

N    = 1024;
Nfft = 2048;

%% DPW dimensions

Nframes = size(f,2);

%% Pre-multiplication chirp (A chirp)

g = f .* Achirp;

%% Zero-padding
%
% Extend each frame from N to Nfft samples to perform the linear
% convolution through frequency-domain multiplication.

g_pad = complex(zeros(Nfft,Nframes,'single'));

g_pad(1:N,:) = g;

%% Frequency-domain convolution
%
% Compute the convolution with the B chirp using the FFT method.

Gfft = fft(g_pad);

G = ifft(Gfft .* H);

%% Extract valid convolution region and decimate
%
% The Ozaktas formulation requires only the valid portion of the
% convolution result, followed by a factor-of-two decimation.

G_valid = G(N+1:2:end,:);

%% Post-multiplication chirp (C chirp)
%
% Apply the final chirp and amplitude factor to obtain the FrFT output.

F = Aa .* G_valid .* Cchirp;

end