1 | #!/usr/bin/env python |
---|
2 | # |
---|
3 | # Copyright 2005,2006,2007,2009 Free Software Foundation, Inc. |
---|
4 | # |
---|
5 | # This file is part of GNU Radio |
---|
6 | # |
---|
7 | # GNU Radio is free software; you can redistribute it and/or modify |
---|
8 | # it under the terms of the GNU General Public License as published by |
---|
9 | # the Free Software Foundation; either version 3, or (at your option) |
---|
10 | # any later version. |
---|
11 | # |
---|
12 | # GNU Radio is distributed in the hope that it will be useful, |
---|
13 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
---|
14 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
---|
15 | # GNU General Public License for more details. |
---|
16 | # |
---|
17 | # You should have received a copy of the GNU General Public License |
---|
18 | # along with GNU Radio; see the file COPYING. If not, write to |
---|
19 | # the Free Software Foundation, Inc., 51 Franklin Street, |
---|
20 | # Boston, MA 02110-1301, USA. |
---|
21 | # |
---|
22 | |
---|
23 | from gnuradio import gr, gru, blks2 |
---|
24 | from gnuradio import usrp |
---|
25 | from gnuradio import eng_notation |
---|
26 | import copy |
---|
27 | import sys |
---|
28 | |
---|
29 | # from current dir |
---|
30 | from pick_bitrate import pick_rx_bitrate |
---|
31 | import usrp_options |
---|
32 | |
---|
33 | # ///////////////////////////////////////////////////////////////////////////// |
---|
34 | # receive path |
---|
35 | # ///////////////////////////////////////////////////////////////////////////// |
---|
36 | |
---|
37 | class receive_path(gr.hier_block2): |
---|
38 | def __init__(self, demod_class, rx_callback, options): |
---|
39 | |
---|
40 | gr.hier_block2.__init__(self, "receive_path", |
---|
41 | gr.io_signature(0, 0, 0), # Input signature |
---|
42 | gr.io_signature(0, 0, 0)) # Output signature |
---|
43 | |
---|
44 | options = copy.copy(options) # make a copy so we can destructively modify |
---|
45 | |
---|
46 | self._verbose = options.verbose |
---|
47 | self._rx_freq = options.rx_freq # receiver's center frequency |
---|
48 | self._rx_gain = options.rx_gain # receiver's gain |
---|
49 | self._bitrate = options.bitrate # desired bit rate |
---|
50 | self._decim = options.decim # Decimating rate for the USRP (prelim) |
---|
51 | self._samples_per_symbol = options.samples_per_symbol # desired samples/symbol |
---|
52 | |
---|
53 | self._rx_callback = rx_callback # this callback is fired when there's a packet available |
---|
54 | self._demod_class = demod_class # the demodulator_class we're using |
---|
55 | |
---|
56 | if self._rx_freq is None: |
---|
57 | sys.stderr.write("-f FREQ or --freq FREQ or --rx-freq FREQ must be specified\n") |
---|
58 | raise SystemExit |
---|
59 | |
---|
60 | # Set up USRP source; also adjusts decim, samples_per_symbol, and bitrate |
---|
61 | self._setup_usrp_source(options) |
---|
62 | |
---|
63 | if options.show_rx_gain_range: |
---|
64 | print "Rx Gain Range: minimum = %g, maximum = %g, step size = %g"%tuple(self.u.gain_range()) |
---|
65 | |
---|
66 | self.set_gain(options.rx_gain) |
---|
67 | |
---|
68 | # Set RF frequency |
---|
69 | ok = self.set_freq(self._rx_freq) |
---|
70 | if not ok: |
---|
71 | print "Failed to set Rx frequency to %s" % (eng_notation.num_to_str(self._rx_freq)) |
---|
72 | raise ValueError, eng_notation.num_to_str(self._rx_freq) |
---|
73 | |
---|
74 | # copy the final answers back into options for use by demodulator |
---|
75 | options.samples_per_symbol = self._samples_per_symbol |
---|
76 | options.bitrate = self._bitrate |
---|
77 | options.decim = self._decim |
---|
78 | |
---|
79 | # Get demod_kwargs |
---|
80 | demod_kwargs = self._demod_class.extract_kwargs_from_options(options) |
---|
81 | |
---|
82 | # Design filter to get actual channel we want |
---|
83 | sw_decim = 1 |
---|
84 | chan_coeffs = gr.firdes.low_pass (1.0, # gain |
---|
85 | sw_decim * self._samples_per_symbol, # sampling rate |
---|
86 | 1.0, # midpoint of trans. band |
---|
87 | 0.5, # width of trans. band |
---|
88 | gr.firdes.WIN_HANN) # filter type |
---|
89 | |
---|
90 | # Decimating channel filter |
---|
91 | # complex in and out, float taps |
---|
92 | self.chan_filt = gr.fft_filter_ccc(sw_decim, chan_coeffs) |
---|
93 | #self.chan_filt = gr.fir_filter_ccf(sw_decim, chan_coeffs) |
---|
94 | |
---|
95 | # receiver |
---|
96 | self.packet_receiver = \ |
---|
97 | blks2.demod_pkts(self._demod_class(**demod_kwargs), |
---|
98 | access_code=None, |
---|
99 | callback=self._rx_callback, |
---|
100 | threshold=-1) |
---|
101 | |
---|
102 | # Carrier Sensing Blocks |
---|
103 | alpha = 0.001 |
---|
104 | thresh = 30 # in dB, will have to adjust |
---|
105 | |
---|
106 | if options.log_rx_power == True: |
---|
107 | self.probe = gr.probe_avg_mag_sqrd_cf(thresh,alpha) |
---|
108 | self.power_sink = gr.file_sink(gr.sizeof_float, "rxpower.dat") |
---|
109 | self.connect(self.chan_filt, self.probe, self.power_sink) |
---|
110 | else: |
---|
111 | self.probe = gr.probe_avg_mag_sqrd_c(thresh,alpha) |
---|
112 | self.connect(self.chan_filt, self.probe) |
---|
113 | |
---|
114 | # Display some information about the setup |
---|
115 | if self._verbose: |
---|
116 | self._print_verbage() |
---|
117 | |
---|
118 | #################################spectrum sense specific code############################# |
---|
119 | |
---|
120 | |
---|
121 | self.min_freq = 462.4825e6 # setting min and max frequency inside the init rather than taking it from the command line |
---|
122 | self.max_freq = 462.4825e6 |
---|
123 | |
---|
124 | if self.min_freq > self.max_freq: |
---|
125 | self.min_freq, self.max_freq = self.max_freq, self.min_freq # swap them |
---|
126 | |
---|
127 | self.fft_size = 128 |
---|
128 | |
---|
129 | |
---|
130 | #if not options.real_time: |
---|
131 | # realtime = False |
---|
132 | |
---|
133 | #else: |
---|
134 | # # Attempt to enable realtime scheduling |
---|
135 | # r = gr.enable_realtime_scheduling() |
---|
136 | # if r == gr.RT_OK: |
---|
137 | # realtime = True |
---|
138 | # else: |
---|
139 | # realtime = False |
---|
140 | # print "Note: failed to enable realtime scheduling" |
---|
141 | |
---|
142 | # If the user hasn't set the fusb_* parameters on the command line, |
---|
143 | # pick some values that will reduce latency. |
---|
144 | |
---|
145 | #if 1: |
---|
146 | # if options.fusb_block_size == 0 and options.fusb_nblocks == 0: |
---|
147 | # if realtime: # be more aggressive |
---|
148 | # options.fusb_block_size = gr.prefs().get_long('fusb', 'rt_block_size', 1024) |
---|
149 | # options.fusb_nblocks = gr.prefs().get_long('fusb', 'rt_nblocks', 16) |
---|
150 | # else: |
---|
151 | # options.fusb_block_size = gr.prefs().get_long('fusb', 'block_size', 4096) |
---|
152 | # options.fusb_nblocks = gr.prefs().get_long('fusb', 'nblocks', 16) |
---|
153 | |
---|
154 | #print "fusb_block_size =", options.fusb_block_size |
---|
155 | #print "fusb_nblocks =", options.fusb_nblocks |
---|
156 | |
---|
157 | # build graph |
---|
158 | |
---|
159 | #self.u = usrp_options.create_usrp_source(options) |
---|
160 | |
---|
161 | |
---|
162 | #adc_rate = self.u.adc_rate() # 64 MS/s |
---|
163 | #usrp_decim = options.decim |
---|
164 | #self.u.set_decim_rate(usrp_decim) |
---|
165 | usrp_rate = adc_rate / usrp_decim |
---|
166 | |
---|
167 | self.u.set_mux(usrp.determine_rx_mux_value(self.u, options.rx_subdev_spec)) |
---|
168 | self.subdev = usrp.selected_subdev(self.u, options.rx_subdev_spec) |
---|
169 | print "Using RX d'board %s" % (self.subdev.side_and_name(),) |
---|
170 | |
---|
171 | |
---|
172 | #s2v = gr.stream_to_vector(gr.sizeof_gr_complex, self.fft_size) |
---|
173 | self.s2v = gr.stream_to_vector(gr.sizeof_gr_complex, self.fft_size) # making it an attribute of the class |
---|
174 | |
---|
175 | mywindow = window.blackmanharris(self.fft_size) |
---|
176 | self.fft = gr.fft_vcc(self.fft_size, True, mywindow) #making it an attribute of the class |
---|
177 | power = 0 |
---|
178 | for tap in mywindow: |
---|
179 | power += tap*tap |
---|
180 | |
---|
181 | #c2mag = gr.complex_to_mag_squared(self.fft_size) # making it an attribute of the class |
---|
182 | self.c2mag = gr.complex_to_mag_squared(self.fft_size) |
---|
183 | print "print c2mag ",c2mag,"\n" |
---|
184 | # FIXME the log10 primitive is dog slow |
---|
185 | log = gr.nlog10_ff(10, self.fft_size, |
---|
186 | -20*math.log10(self.fft_size)-10*math.log10(power/self.fft_size)) |
---|
187 | |
---|
188 | # Set the freq_step to 75% of the actual data throughput. |
---|
189 | # This allows us to discard the bins on both ends of the spectrum. |
---|
190 | |
---|
191 | self.freq_step = 0.75 * usrp_rate |
---|
192 | self.min_center_freq = self.min_freq + self.freq_step/2 |
---|
193 | nsteps = math.ceil((self.max_freq - self.min_freq) / self.freq_step) |
---|
194 | self.max_center_freq = self.min_center_freq + (nsteps * self.freq_step) |
---|
195 | |
---|
196 | self.next_freq = self.min_center_freq |
---|
197 | |
---|
198 | tune_delay = max(0, int(round(options.tune_delay * usrp_rate / self.fft_size))) # in fft_frames |
---|
199 | dwell_delay = max(1, int(round(options.dwell_delay * usrp_rate / self.fft_size))) # in fft_frames |
---|
200 | |
---|
201 | self.msgq = gr.msg_queue(16) |
---|
202 | self._tune_callback = tune(self) # hang on to this to keep it from being GC'd |
---|
203 | #stats = gr.bin_statistics_f(self.fft_size, self.msgq, |
---|
204 | # self._tune_callback, tune_delay, dwell_delay) |
---|
205 | |
---|
206 | self.stats = gr.bin_statistics_f(self.fft_size, self.msgq, |
---|
207 | self._tune_callback, tune_delay, dwell_delay) #making it an attribute of the class |
---|
208 | |
---|
209 | |
---|
210 | |
---|
211 | # FIXME leave out the log10 until we speed it up |
---|
212 | #self.connect(self.u, s2v, fft, c2mag, log, stats) |
---|
213 | #self.connect(self.u, s2v, fft, c2mag, stats) # taking care of the connect in benchmark_txrx |
---|
214 | |
---|
215 | if options.gain is None: |
---|
216 | # if no gain was specified, use the mid-point in dB |
---|
217 | g = self.subdev.gain_range() |
---|
218 | options.gain = float(g[0]+g[1])/2 |
---|
219 | |
---|
220 | self.set_gain(options.gain) |
---|
221 | print "gain =", options.gain |
---|
222 | |
---|
223 | ########################################################################################## |
---|
224 | |
---|
225 | self.connect(self.u, self.chan_filt, self.packet_receiver) |
---|
226 | self.connect(self.u, s2v) |
---|
227 | |
---|
228 | def _setup_usrp_source(self, options): |
---|
229 | |
---|
230 | self.u = usrp_options.create_usrp_source(options) |
---|
231 | adc_rate = self.u.adc_rate() |
---|
232 | |
---|
233 | # derive values of bitrate, samples_per_symbol, and decim from desired info |
---|
234 | (self._bitrate, self._samples_per_symbol, self._decim) = \ |
---|
235 | pick_rx_bitrate(self._bitrate, self._demod_class.bits_per_symbol(), \ |
---|
236 | self._samples_per_symbol, self._decim, adc_rate) |
---|
237 | |
---|
238 | self.u.set_decim(self._decim) |
---|
239 | |
---|
240 | def set_freq(self, target_freq): |
---|
241 | """ |
---|
242 | Set the center frequency we're interested in. |
---|
243 | |
---|
244 | @param target_freq: frequency in Hz |
---|
245 | @rypte: bool |
---|
246 | |
---|
247 | Tuning is a two step process. First we ask the front-end to |
---|
248 | tune as close to the desired frequency as it can. Then we use |
---|
249 | the result of that operation and our target_frequency to |
---|
250 | determine the value for the digital up converter. |
---|
251 | """ |
---|
252 | return self.u.set_center_freq(target_freq) |
---|
253 | |
---|
254 | def set_gain(self, gain): |
---|
255 | """ |
---|
256 | Sets the analog gain in the USRP |
---|
257 | """ |
---|
258 | return self.u.set_gain(gain) |
---|
259 | |
---|
260 | def bitrate(self): |
---|
261 | return self._bitrate |
---|
262 | |
---|
263 | def samples_per_symbol(self): |
---|
264 | return self._samples_per_symbol |
---|
265 | |
---|
266 | def decim(self): |
---|
267 | return self._decim |
---|
268 | |
---|
269 | def carrier_sensed(self): |
---|
270 | """ |
---|
271 | Return True if we think carrier is present. |
---|
272 | """ |
---|
273 | #return self.probe.level() > X |
---|
274 | return self.probe.unmuted() |
---|
275 | |
---|
276 | def carrier_threshold(self): |
---|
277 | """ |
---|
278 | Return current setting in dB. |
---|
279 | """ |
---|
280 | return self.probe.threshold() |
---|
281 | |
---|
282 | def set_carrier_threshold(self, threshold_in_db): |
---|
283 | """ |
---|
284 | Set carrier threshold. |
---|
285 | |
---|
286 | @param threshold_in_db: set detection threshold |
---|
287 | @type threshold_in_db: float (dB) |
---|
288 | """ |
---|
289 | self.probe.set_threshold(threshold_in_db) |
---|
290 | |
---|
291 | @staticmethod |
---|
292 | def add_options(normal, expert): |
---|
293 | """ |
---|
294 | Adds receiver-specific options to the Options Parser |
---|
295 | """ |
---|
296 | add_freq_option(normal) |
---|
297 | if not normal.has_option("--bitrate"): |
---|
298 | normal.add_option("-r", "--bitrate", type="eng_float", default=None, |
---|
299 | help="specify bitrate. samples-per-symbol and interp/decim will be derived.") |
---|
300 | usrp_options.add_rx_options(normal, expert) |
---|
301 | normal.add_option("-v", "--verbose", action="store_true", default=False) |
---|
302 | expert.add_option("-S", "--samples-per-symbol", type="int", default=None, |
---|
303 | help="set samples/symbol [default=%default]") |
---|
304 | expert.add_option("", "--rx-freq", type="eng_float", default=None, |
---|
305 | help="set Rx frequency to FREQ [default=%default]", metavar="FREQ") |
---|
306 | expert.add_option("", "--log", action="store_true", default=False, |
---|
307 | help="Log all parts of flow graph to files (CAUTION: lots of data)") |
---|
308 | expert.add_option("", "--log-rx-power", action="store_true", default=False, |
---|
309 | help="Log receive signal power to file (CAUTION: lots of data)") |
---|
310 | |
---|
311 | def _print_verbage(self): |
---|
312 | """ |
---|
313 | Prints information about the receive path |
---|
314 | """ |
---|
315 | print "\nReceive Path:" |
---|
316 | print "USRP %s" % (self.u,) |
---|
317 | print "Rx gain: %g" % (self.u.gain(),) |
---|
318 | print "modulation: %s" % (self._demod_class.__name__) |
---|
319 | print "bitrate: %sb/s" % (eng_notation.num_to_str(self._bitrate)) |
---|
320 | print "samples/symbol: %3d" % (self._samples_per_symbol) |
---|
321 | print "decim: %3d" % (self._decim) |
---|
322 | print "Rx Frequency: %s" % (eng_notation.num_to_str(self._rx_freq)) |
---|
323 | |
---|
324 | def add_freq_option(parser): |
---|
325 | """ |
---|
326 | Hackery that has the -f / --freq option set both tx_freq and rx_freq |
---|
327 | """ |
---|
328 | def freq_callback(option, opt_str, value, parser): |
---|
329 | parser.values.rx_freq = value |
---|
330 | parser.values.tx_freq = value |
---|
331 | |
---|
332 | if not parser.has_option('--freq'): |
---|
333 | parser.add_option('-f', '--freq', type="eng_float", |
---|
334 | action="callback", callback=freq_callback, |
---|
335 | help="set Tx and/or Rx frequency to FREQ [default=%default]", |
---|
336 | metavar="FREQ") |
---|
337 | |
---|
338 | |
---|
339 | ##################### Spectrum sense specific classes################################## |
---|
340 | |
---|
341 | class tune(gr.feval_dd): |
---|
342 | """ |
---|
343 | This class allows C++ code to callback into python. |
---|
344 | """ |
---|
345 | def __init__(self, tb): |
---|
346 | gr.feval_dd.__init__(self) |
---|
347 | self.tb = tb |
---|
348 | |
---|
349 | def eval(self, ignore): |
---|
350 | """ |
---|
351 | This method is called from gr.bin_statistics_f when it wants to change |
---|
352 | the center frequency. This method tunes the front end to the new center |
---|
353 | frequency, and returns the new frequency as its result. |
---|
354 | """ |
---|
355 | try: |
---|
356 | # We use this try block so that if something goes wrong from here |
---|
357 | # down, at least we'll have a prayer of knowing what went wrong. |
---|
358 | # Without this, you get a very mysterious: |
---|
359 | # |
---|
360 | # terminate called after throwing an instance of 'Swig::DirectorMethodException' |
---|
361 | # Aborted |
---|
362 | # |
---|
363 | # message on stderr. Not exactly helpful ;) |
---|
364 | |
---|
365 | new_freq = self.tb.set_next_freq() |
---|
366 | return new_freq |
---|
367 | |
---|
368 | except Exception, e: |
---|
369 | print "tune: Exception: ", e |
---|
370 | |
---|
371 | |
---|
372 | class parse_msg(object): |
---|
373 | def __init__(self, msg): |
---|
374 | self.center_freq = msg.arg1() |
---|
375 | self.vlen = int(msg.arg2()) |
---|
376 | assert(msg.length() == self.vlen * gr.sizeof_float) |
---|
377 | |
---|
378 | # FIXME consider using Numarray or NumPy vector |
---|
379 | t = msg.to_string() |
---|
380 | self.raw_data = t |
---|
381 | self.data = struct.unpack('%df' % (self.vlen,), t) |
---|
382 | |
---|
383 | |
---|
384 | ######################################################################################## |
---|