Merge commit 'v3.3.1' into try-3.3.1

[debian/gnuradio] / gnuradio-examples / python / pfb / synth_filter.py

diff --git a/gnuradio-examples/python/pfb/synth_filter.py b/gnuradio-examples/python/pfb/synth_filter.py
new file mode 100755 (executable)
index 0000000..a1562f9
--- /dev/null
+++ b/gnuradio-examples/python/pfb/synth_filter.py
@@ -0,0 +1,71 @@
+#!/usr/bin/env python
+#
+# Copyright 2010 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.
+# 
+
+from gnuradio import gr, blks2
+import scipy, pylab
+
+def main():
+    N = 1000000
+    fs = 8000
+
+    freqs = [100, 200, 300, 400, 500]
+    nchans = 7
+
+    sigs = list()
+    for fi in freqs:
+        s = gr.sig_source_c(fs, gr.GR_SIN_WAVE, fi, 1)
+        sigs.append(s)
+
+    taps = gr.firdes.low_pass_2(len(freqs), fs, fs/float(nchans)/2, 100, 100)
+    print "Num. Taps = %d (taps per filter = %d)" % (len(taps), 
+                                                     len(taps)/nchans)
+    filtbank = gr.pfb_synthesis_filterbank_ccf(nchans, taps)
+
+    head = gr.head(gr.sizeof_gr_complex, N)
+    snk = gr.vector_sink_c()
+
+    tb = gr.top_block()
+    tb.connect(filtbank, head, snk)
+
+    for i,si in enumerate(sigs):
+        tb.connect(si, (filtbank, i))
+    
+    tb.run()
+
+    if 1:
+        f1 = pylab.figure(1)
+        s1 = f1.add_subplot(1,1,1)
+        s1.plot(snk.data()[1000:])
+        
+        fftlen = 2048
+        f2 = pylab.figure(2)
+        s2 = f2.add_subplot(1,1,1)
+        winfunc = scipy.blackman
+        s2.psd(snk.data()[10000:], NFFT=fftlen,
+               Fs = nchans*fs,
+               noverlap=fftlen/4,
+               window = lambda d: d*winfunc(fftlen))
+
+        pylab.show()
+
+if __name__ == "__main__":
+    main()