Merge branch 'dfsg-orig'

[debian/gnuradio] / gnuradio-core / src / utils / plot_cic_decimator_response.m

diff --git a/gnuradio-core/src/utils/plot_cic_decimator_response.m b/gnuradio-core/src/utils/plot_cic_decimator_response.m
new file mode 100644 (file)
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+++ b/gnuradio-core/src/utils/plot_cic_decimator_response.m
@@ -0,0 +1,45 @@
+#
+# 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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