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#
# Copyright 2004 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# GNU Radio is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3, or (at your option)
# any later version.
#
# GNU Radio is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING. If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
#
function plot_cic_decimator_response (R, N, M)
## R = decimation rate
## N = number of stages (4)
## M = 1
gain = (R*M)^N
npoints = 1024;
w = 0:1/npoints:1-1/npoints;
w = w * 1 * pi;
## w = w * R;
length(w);
num = sin (w*R*M/2);
length (num);
## H = sin (w*R*M/2) ./ sin (w/2)
denom = sin(w/2);
length (denom);
H = (num ./ denom) .^ N;
H(1) = gain;
H = H ./ gain;
plot (R*w/(2*pi), 10 * log10 (H));
## plot (R*w/(2*pi), H);
endfunction
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