git.gag.com Git - debian/gnuradio/blob - gnuradio-examples/python/usrp/test_dft_analysis.py

   1 #!/usr/bin/env python
   2
   3 from gnuradio import gr, gru, blks
   4 from gnuradio.wxgui import stdgui, fftsink, slider
   5 from gnuradio.eng_option import eng_option
   6 from optparse import OptionParser
   7 import wx
   8
   9 class test_graph (stdgui.gui_flow_graph):
  10     def __init__(self, frame, panel, vbox, argv):
  11         stdgui.gui_flow_graph.__init__(self, frame, panel, vbox, argv)
  12
  13         parser = OptionParser (option_class=eng_option)
  14         (options, args) = parser.parse_args ()
  15
  16         sample_rate = 16e3
  17         mpoints = 4
  18         ampl = 1000
  19         freq = 0
  20
  21         lo_freq = 1e6
  22         lo_ampl = 1
  23
  24         vbox.Add(slider.slider(panel,
  25                                -sample_rate/2, sample_rate/2,
  26                                self.set_lo_freq), 0, wx.ALIGN_CENTER)
  27
  28
  29         src = gr.sig_source_c(sample_rate, gr.GR_CONST_WAVE,
  30                               freq, ampl, 0)
  31
  32         self.lo = gr.sig_source_c(sample_rate, gr.GR_SIN_WAVE,
  33                                   lo_freq, lo_ampl, 0)
  34
  35         mixer = gr.multiply_cc()
  36         self.connect(src, (mixer, 0))
  37         self.connect(self.lo, (mixer, 1))
  38
  39         # We add these throttle blocks so that this demo doesn't
  40         # suck down all the CPU available.  Normally you wouldn't use these.
  41         thr = gr.throttle(gr.sizeof_gr_complex, sample_rate)
  42
  43         taps = gr.firdes.low_pass(1,   # gain
  44                                   1,   # rate
  45                                   1.0/mpoints * 0.4,  # cutoff
  46                                   1.0/mpoints * 0.1,  # trans width
  47                                   gr.firdes.WIN_HANN)
  48         print len(taps)
  49         analysis = blks.analysis_filterbank(self, mpoints, taps)
  50
  51         self.connect(mixer, thr)
  52         self.connect(thr, analysis)
  53
  54         for i in range(mpoints):
  55             fft = fftsink.fft_sink_c(self, frame, fft_size=128,
  56                                      sample_rate=sample_rate/mpoints,
  57                                      fft_rate=5,
  58                                      title="Ch %d" % (i,))
  59             self.connect((analysis, i), fft)
  60             vbox.Add(fft.win, 1, wx.EXPAND)
  61
  62     def set_lo_freq(self, freq):
  63         self.lo.set_frequency(freq)
  64
  65
  66
  67 def main ():
  68     app = stdgui.stdapp (test_graph, "Test DFT filterbank")
  69     app.MainLoop ()
  70
  71 if __name__ == '__main__':
  72     main ()