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

   1 #!/usr/bin/env python
   2
   3 from gnuradio import gr, gru, blks
   4 from gnuradio.wxgui import stdgui, fftsink
   5 from gnuradio.eng_option import eng_option
   6 from optparse import OptionParser
   7 import wx
   8 import random
   9
  10
  11 def make_random_complex_tuple(L, gain=1):
  12     result = []
  13     for x in range(L):
  14         result.append(gain * complex(random.gauss(0, 1),random.gauss(0, 1)))
  15
  16     return tuple(result)
  17
  18 def random_noise_c(gain=1):
  19     src = gr.vector_source_c(make_random_complex_tuple(32*1024, gain), True)
  20     return src
  21
  22
  23 class test_graph (stdgui.gui_flow_graph):
  24     def __init__(self, frame, panel, vbox, argv):
  25         stdgui.gui_flow_graph.__init__(self, frame, panel, vbox, argv)
  26
  27         parser = OptionParser (option_class=eng_option)
  28         (options, args) = parser.parse_args ()
  29
  30         sample_rate = 16e6
  31         mpoints = 16
  32         ampl = 1000
  33
  34         enable = mpoints * [0]
  35         enable[0] = 1
  36
  37         taps = gr.firdes.low_pass(1,   # gain
  38                                   1,   # rate
  39                                   1.0/mpoints * 0.4,  # cutoff
  40                                   1.0/mpoints * 0.1,  # trans width
  41                                   gr.firdes.WIN_HANN)
  42
  43         synth = blks.synthesis_filterbank(self, mpoints, taps)
  44
  45         null_source = gr.null_source(gr.sizeof_gr_complex)
  46
  47         if 0:
  48             for i in range(mpoints):
  49                 s = gr.sig_source_c(sample_rate/mpoints, gr.GR_SIN_WAVE,
  50                                     300e3, ampl * enable[i], 0)
  51                 self.connect(s, (synth, i))
  52
  53         else:
  54             for i in range(mpoints):
  55                 if i == 0:
  56                     s = gr.sig_source_c(sample_rate/mpoints, gr.GR_SIN_WAVE,
  57                                         300e3, ampl * enable[i], 0)
  58                     #s = random_noise_c(ampl)
  59                     self.connect(s, (synth, i))
  60                 else:
  61                     self.connect(null_source, (synth, i))
  62
  63
  64         # We add these throttle blocks so that this demo doesn't
  65         # suck down all the CPU available.  Normally you wouldn't use these.
  66         thr = gr.throttle(gr.sizeof_gr_complex, sample_rate)
  67         fft = fftsink.fft_sink_c(self, frame, fft_size=1024,
  68                                  sample_rate=sample_rate)
  69         vbox.Add(fft.win, 1, wx.EXPAND)
  70
  71         self.connect(synth, thr, fft)
  72
  73
  74 def main ():
  75     app = stdgui.stdapp (test_graph, "Test DFT filterbank")
  76     app.MainLoop ()
  77
  78 if __name__ == '__main__':
  79     main ()