2 ##################################################
3 # Gnuradio Python Flow Graph
4 # Title: USRP HRPT Receiver
5 # Generated: Wed Sep 23 11:37:25 2009
6 ##################################################
8 from gnuradio import eng_notation
9 from gnuradio import gr
10 from gnuradio import noaa
11 from gnuradio.eng_option import eng_option
12 from gnuradio.gr import firdes
13 from optparse import OptionParser
16 class demod_hrpt_file(gr.top_block):
18 def __init__(self, decim=16, pll_alpha=0.05, sync_alpha=0.05, filename="usrp.dat", output="frames.dat"):
19 gr.top_block.__init__(self, "USRP HRPT Receiver")
21 ##################################################
23 ##################################################
25 self.pll_alpha = pll_alpha
26 self.sync_alpha = sync_alpha
27 self.filename = filename
30 ##################################################
32 ##################################################
33 self.sym_rate = sym_rate = 600*1109
34 self.sample_rate = sample_rate = 64e6/decim
35 self.sps = sps = sample_rate/sym_rate
36 self.max_sync_offset = max_sync_offset = 0.01
37 self.max_carrier_offset = max_carrier_offset = 2*math.pi*100e3/sample_rate
38 self.hs = hs = int(sps/2.0)
40 ##################################################
42 ##################################################
43 self.decoder = noaa.hrpt_decoder()
44 self.deframer = noaa.hrpt_deframer()
45 self.deinterleave = gr.deinterleave(gr.sizeof_float*1)
46 self.f2c = gr.float_to_complex(1)
47 self.file_sink = gr.file_sink(gr.sizeof_short*1, output)
48 self.file_source = gr.file_source(gr.sizeof_short*1, filename, False)
49 self.matched_filter = gr.moving_average_cc(hs, 1.0/hs, 4000)
50 self.pll = noaa.hrpt_pll_cf(pll_alpha, pll_alpha**2/4.0, max_carrier_offset)
51 self.s2f = gr.short_to_float()
52 self.sync = noaa.hrpt_sync_fb(sync_alpha, sync_alpha**2/4.0, sps, max_sync_offset)
54 ##################################################
56 ##################################################
57 self.connect((self.deframer, 0), (self.file_sink, 0))
58 self.connect((self.sync, 0), (self.deframer, 0))
59 self.connect((self.pll, 0), (self.sync, 0))
60 self.connect((self.matched_filter, 0), (self.pll, 0))
61 self.connect((self.s2f, 0), (self.deinterleave, 0))
62 self.connect((self.deinterleave, 1), (self.f2c, 1))
63 self.connect((self.deinterleave, 0), (self.f2c, 0))
64 self.connect((self.file_source, 0), (self.s2f, 0))
65 self.connect((self.deframer, 0), (self.decoder, 0))
66 self.connect((self.f2c, 0), (self.matched_filter, 0))
68 def set_decim(self, decim):
70 self.set_sample_rate(64e6/self.decim)
72 def set_pll_alpha(self, pll_alpha):
73 self.pll_alpha = pll_alpha
74 self.pll.set_alpha(self.pll_alpha)
75 self.pll.set_beta(self.pll_alpha**2/4.0)
77 def set_sync_alpha(self, sync_alpha):
78 self.sync_alpha = sync_alpha
79 self.sync.set_alpha(self.sync_alpha)
80 self.sync.set_beta(self.sync_alpha**2/4.0)
82 def set_filename(self, filename):
83 self.filename = filename
85 def set_output(self, output):
88 def set_sym_rate(self, sym_rate):
89 self.sym_rate = sym_rate
90 self.set_sps(self.sample_rate/self.sym_rate)
92 def set_sample_rate(self, sample_rate):
93 self.sample_rate = sample_rate
94 self.set_max_carrier_offset(2*math.pi*100e3/self.sample_rate)
95 self.set_sps(self.sample_rate/self.sym_rate)
97 def set_sps(self, sps):
99 self.set_hs(int(self.sps/2.0))
101 def set_max_sync_offset(self, max_sync_offset):
102 self.max_sync_offset = max_sync_offset
103 self.sync.set_max_offset(self.max_sync_offset)
105 def set_max_carrier_offset(self, max_carrier_offset):
106 self.max_carrier_offset = max_carrier_offset
107 self.pll.set_max_offset(self.max_carrier_offset)
109 def set_hs(self, hs):
111 self.matched_filter.set_length_and_scale(self.hs, 1.0/self.hs)
113 if __name__ == '__main__':
114 parser = OptionParser(option_class=eng_option, usage="%prog: [options]")
115 parser.add_option("-d", "--decim", dest="decim", type="intx", default=16,
116 help="Set Decimation [default=%default]")
117 parser.add_option("-p", "--pll-alpha", dest="pll_alpha", type="eng_float", default=eng_notation.num_to_str(0.05),
118 help="Set pll_alpha [default=%default]")
119 parser.add_option("-s", "--sync-alpha", dest="sync_alpha", type="eng_float", default=eng_notation.num_to_str(0.05),
120 help="Set sync_alpha [default=%default]")
121 parser.add_option("-F", "--filename", dest="filename", type="string", default="usrp.dat",
122 help="Set Filename [default=%default]")
123 parser.add_option("-o", "--output", dest="output", type="string", default="frames.dat",
124 help="Set Output [default=%default]")
125 (options, args) = parser.parse_args()
126 tb = demod_hrpt_file(decim=options.decim, pll_alpha=options.pll_alpha, sync_alpha=options.sync_alpha, filename=options.filename, output=options.output)
128 raw_input('Press Enter to quit: ')