deemph_us_40K625.m

%    FM deemphasis filter generator (US)
%    Copyright (C) 2024  Patrik Kluba <kpajko79@gmail.com>
%
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%    of this software and associated documentation files (the "Software"), to deal
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%    SPDX-License-Identifier: MIT

function [Hd, name, Fs, pbfs, sbfs] = deemph_us_40K625

Fs = 40625;

N   = 1;
tau = 75e-6;

Fc = 1/(2*pi*tau);
h  = fdesign.lowpass('N,F3dB', N, Fc, Fs);
Hd = design(h, 'butter', 'FilterStructure', 'df1sos');

[b, a] = tf(Hd);
Hd = dfilt.df1(b, a);

name = sprintf("FM de-emphasis filter for %.3f Ksps (US)", Fs/1000);
pbfs = [0 Fs/2];
sbfs = [];

% [EOF]