[gsm-receiver] add gsm-receiver script for usrp2

1 files changed, 148 insertions, 0 deletions

diff --git a/gsm-receiver/src/python/gsm_receive_usrp2.py b/gsm-receiver/src/python/gsm_receive_usrp2.py
new file mode 100755
index 0000000..a5ca75e
--- /dev/null
+++ b/gsm-receiver/src/python/gsm_receive_usrp2.py
@@ -0,0 +1,148 @@
+#!/usr/bin/env python
+#this file isn't ready to use now - gsm-receiver lacks realtime processing capability 
+#there are many underruns of buffer for samples from usrp's, many blocks of samples get lost and
+#receiver isn't prepared for this situation too well
+
+from gnuradio import gr, gru, blks2
+#, gsm
+from gnuradio import usrp2
+from gnuradio.eng_option import eng_option
+from optparse import OptionParser
+from os import sys
+
+for extdir in ['../../debug/src/lib','../../debug/src/lib/.libs','../lib','../lib/.libs']:
+    if extdir not in sys.path:
+        sys.path.append(extdir)
+import gsm                        
+
+def pick_subdevice(u):
+    if u.db[0][0].dbid() >= 0:
+        return (0, 0)
+    if u.db[1][0].dbid() >= 0:
+        return (1, 0)
+    return (0, 0)
+
+class tuner(gr.feval_dd):
+    def __init__(self, top_block):
+        gr.feval_dd.__init__(self)
+        self.top_block = top_block
+    def eval(self, freq_offet):
+        self.top_block.set_center_frequency(freq_offet)
+        return freq_offet
+        
+class synchronizer(gr.feval_dd):
+    def __init__(self, top_block):
+        gr.feval_dd.__init__(self)
+        self.top_block = top_block
+
+    def eval(self, timing_offset):
+        self.top_block.set_timing(timing_offset)
+        return freq_offet
+
+class gsm_receiver_first_blood(gr.top_block):
+    def __init__(self):
+        gr.top_block.__init__(self)
+        (options, args) = self._process_options()
+        self.tuner_callback = tuner(self)
+        self.synchronizer_callback = synchronizer(self)
+        self.options    = options
+        self.args       = args
+        self._set_rates()
+        self.source = self._set_source()
+        self.filtr = self._set_filter()
+        self.interpolator = self._set_interpolator()
+        self.receiver = self._set_receiver()
+        self.converter = self._set_converter()
+        self.sink = self._set_sink()
+    
+        self.connect(self.source, self.filtr,  self.interpolator, self.receiver, self.converter, self.sink)
+  
+    def _set_sink(self):
+        nazwa_pliku_wy = self.options.outputfile
+        ujscie = gr.file_sink(gr.sizeof_float, nazwa_pliku_wy)
+        return ujscie
+    
+    def _set_source(self):
+        options = self.options
+        self.usrp = usrp2.source_32fc(options.interface, options.mac_addr)
+	self.usrp.set_decim(options.decim)
+        
+        # determine the daughterboard subdevice
+        input_rate = self.usrp.adc_rate() / options.decim
+
+        # set initial values
+        if options.gain is None:
+            # if no gain was specified, use the mid-point in dB
+            g = self.usrp.gain_range()
+            options.gain = float(g[0]+g[1])/2
+
+        r = self.usrp.set_center_freq(options.freq)
+        self.usrp.set_gain(options.gain)
+        return self.usrp
+    
+    def _set_rates(self):
+        options = self.options
+        clock_rate = 100e6
+        self.clock_rate = clock_rate
+        self.input_rate = clock_rate / options.decim
+        self.gsm_symb_rate = 1625000.0 / 6.0
+        self.sps = self.input_rate / self.gsm_symb_rate / self.options.osr
+
+    def _set_filter(self):
+        filter_cutoff   = 145e3	
+        filter_t_width  = 10e3
+        offset = 0
+#        print "input_rate:", self.input_rate, "sample rate:", self.sps, " filter_cutoff:", filter_cutoff, " filter_t_width:", filter_t_width
+        filter_taps     = gr.firdes.low_pass(1.0, self.input_rate, filter_cutoff, filter_t_width, gr.firdes.WIN_HAMMING)
+        filtr          = gr.freq_xlating_fir_filter_ccf(1, filter_taps, offset, self.input_rate)
+        return filtr
+
+    def _set_converter(self):
+        v2s = gr.vector_to_stream(gr.sizeof_float, 142)
+        return v2s
+    
+    def _set_interpolator(self):
+        interpolator = gr.fractional_interpolator_cc(0, self.sps) 
+        return interpolator
+    
+    def _set_receiver(self):
+        receiver = gsm.receiver_cf(self.tuner_callback, self.synchronizer_callback, self.options.osr, "0000000000000000")
+        return receiver
+    
+    def _process_options(self):
+        parser = OptionParser(option_class=eng_option)
+	parser.add_option("-e", "--interface", type="string", default="eth0",
+			  help="select Ethernet interface, default is eth0")
+	parser.add_option("-m", "--mac-addr", type="string", default="",
+			  help="select USRP by MAC address, default is auto-select")
+        parser.add_option("-d", "--decim", type="int", default=112,
+                                    help="Set USRP decimation rate to DECIM [default=%default]")
+        parser.add_option("-I", "--inputfile", type="string", default="cfile",
+                                    help="Input filename")
+        parser.add_option("-O", "--outputfile", type="string", default="cfile2.out",
+                                    help="Output filename")
+        parser.add_option("-r", "--osr", type="int", default=4,
+                          help="Oversampling ratio [default=%default]")
+        parser.add_option("-f", "--freq", type="eng_float", default="950.4M",
+                                    help="set frequency to FREQ", metavar="FREQ")
+        parser.add_option("-g", "--gain", type="eng_float", default=None,
+                                    help="Set gain in dB (default is midpoint)")
+        (options, args) = parser.parse_args ()
+        return (options, args)
+    
+    def set_center_frequency(self, center_freq):
+        self.filtr.set_center_freq(center_freq)
+
+    def set_timing(self, timing_offset):
+        pass
+
+def main():
+    try:
+        gsm_receiver_first_blood().run()
+    except KeyboardInterrupt:
+        pass
+
+if __name__ == '__main__':
+    main()
+
+