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Diffstat (limited to 'gnuradio-examples/python/pfb/decimate.py')
| -rwxr-xr-x | gnuradio-examples/python/pfb/decimate.py | 178 |
1 files changed, 0 insertions, 178 deletions
diff --git a/gnuradio-examples/python/pfb/decimate.py b/gnuradio-examples/python/pfb/decimate.py deleted file mode 100755 index 643a2c241..000000000 --- a/gnuradio-examples/python/pfb/decimate.py +++ /dev/null @@ -1,178 +0,0 @@ -#!/usr/bin/env python -# -# Copyright 2009 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 sys, time - -try: - import scipy - from scipy import fftpack -except ImportError: - print "Error: Program requires scipy (see: www.scipy.org)." - sys.exit(1) - -try: - import pylab - from pylab import mlab -except ImportError: - print "Error: Program requires matplotlib (see: matplotlib.sourceforge.net)." - sys.exit(1) - -class pfb_top_block(gr.top_block): - def __init__(self): - gr.top_block.__init__(self) - - self._N = 10000000 # number of samples to use - self._fs = 10000 # initial sampling rate - self._decim = 20 # Decimation rate - - # Generate the prototype filter taps for the decimators with a 200 Hz bandwidth - self._taps = gr.firdes.low_pass_2(1, self._fs, 200, 150, - attenuation_dB=120, window=gr.firdes.WIN_BLACKMAN_hARRIS) - - # Calculate the number of taps per channel for our own information - tpc = scipy.ceil(float(len(self._taps)) / float(self._decim)) - print "Number of taps: ", len(self._taps) - print "Number of filters: ", self._decim - print "Taps per channel: ", tpc - - # Build the input signal source - # We create a list of freqs, and a sine wave is generated and added to the source - # for each one of these frequencies. - self.signals = list() - self.add = gr.add_cc() - freqs = [10, 20, 2040] - for i in xrange(len(freqs)): - self.signals.append(gr.sig_source_c(self._fs, gr.GR_SIN_WAVE, freqs[i], 1)) - self.connect(self.signals[i], (self.add,i)) - - self.head = gr.head(gr.sizeof_gr_complex, self._N) - - # Construct a PFB decimator filter - self.pfb = blks2.pfb_decimator_ccf(self._decim, self._taps, 0) - - # Construct a standard FIR decimating filter - self.dec = gr.fir_filter_ccf(self._decim, self._taps) - - self.snk_i = gr.vector_sink_c() - - # Connect the blocks - self.connect(self.add, self.head, self.pfb) - self.connect(self.add, self.snk_i) - - # Create the sink for the decimated siganl - self.snk = gr.vector_sink_c() - self.connect(self.pfb, self.snk) - - -def main(): - tb = pfb_top_block() - - tstart = time.time() - tb.run() - tend = time.time() - print "Run time: %f" % (tend - tstart) - - if 1: - fig1 = pylab.figure(1, figsize=(16,9)) - fig2 = pylab.figure(2, figsize=(16,9)) - - Ns = 10000 - Ne = 10000 - - fftlen = 8192 - winfunc = scipy.blackman - fs = tb._fs - - # Plot the input to the decimator - - d = tb.snk_i.data()[Ns:Ns+Ne] - sp1_f = fig1.add_subplot(2, 1, 1) - - X,freq = mlab.psd(d, NFFT=fftlen, noverlap=fftlen/4, Fs=fs, - window = lambda d: d*winfunc(fftlen), - scale_by_freq=True) - X_in = 10.0*scipy.log10(abs(fftpack.fftshift(X))) - f_in = scipy.arange(-fs/2.0, fs/2.0, fs/float(X_in.size)) - p1_f = sp1_f.plot(f_in, X_in, "b") - sp1_f.set_xlim([min(f_in), max(f_in)+1]) - sp1_f.set_ylim([-200.0, 50.0]) - - sp1_f.set_title("Input Signal", weight="bold") - sp1_f.set_xlabel("Frequency (Hz)") - sp1_f.set_ylabel("Power (dBW)") - - Ts = 1.0/fs - Tmax = len(d)*Ts - - t_in = scipy.arange(0, Tmax, Ts) - x_in = scipy.array(d) - sp1_t = fig1.add_subplot(2, 1, 2) - p1_t = sp1_t.plot(t_in, x_in.real, "b") - p1_t = sp1_t.plot(t_in, x_in.imag, "r") - sp1_t.set_ylim([-tb._decim*1.1, tb._decim*1.1]) - - sp1_t.set_xlabel("Time (s)") - sp1_t.set_ylabel("Amplitude") - - - # Plot the output of the decimator - fs_o = tb._fs / tb._decim - - sp2_f = fig2.add_subplot(2, 1, 1) - d = tb.snk.data()[Ns:Ns+Ne] - X,freq = mlab.psd(d, NFFT=fftlen, noverlap=fftlen/4, Fs=fs_o, - window = lambda d: d*winfunc(fftlen), - scale_by_freq=True) - X_o = 10.0*scipy.log10(abs(fftpack.fftshift(X))) - f_o = scipy.arange(-fs_o/2.0, fs_o/2.0, fs_o/float(X_o.size)) - p2_f = sp2_f.plot(f_o, X_o, "b") - sp2_f.set_xlim([min(f_o), max(f_o)+1]) - sp2_f.set_ylim([-200.0, 50.0]) - - sp2_f.set_title("PFB Decimated Signal", weight="bold") - sp2_f.set_xlabel("Frequency (Hz)") - sp2_f.set_ylabel("Power (dBW)") - - - Ts_o = 1.0/fs_o - Tmax_o = len(d)*Ts_o - - x_o = scipy.array(d) - t_o = scipy.arange(0, Tmax_o, Ts_o) - sp2_t = fig2.add_subplot(2, 1, 2) - p2_t = sp2_t.plot(t_o, x_o.real, "b-o") - p2_t = sp2_t.plot(t_o, x_o.imag, "r-o") - sp2_t.set_ylim([-2.5, 2.5]) - - sp2_t.set_xlabel("Time (s)") - sp2_t.set_ylabel("Amplitude") - - pylab.show() - - -if __name__ == "__main__": - try: - main() - except KeyboardInterrupt: - pass - |