diff options
Diffstat (limited to 'python/trx/radio_if.py')
| -rw-r--r-- | python/trx/radio_if.py | 104 |
1 files changed, 84 insertions, 20 deletions
diff --git a/python/trx/radio_if.py b/python/trx/radio_if.py index dbccae7..1ded337 100644 --- a/python/trx/radio_if.py +++ b/python/trx/radio_if.py @@ -29,12 +29,14 @@ import osmosdr from math import pi -from gnuradio.filter import firdes from gnuradio import digital from gnuradio import blocks from gnuradio import uhd from gnuradio import gr +from gnuradio import filter +from gnuradio.filter import firdes + # HACK: should be implemented in C++! class burst_to_fn_time(gr.basic_block): @@ -55,10 +57,29 @@ class burst_to_fn_time(gr.basic_block): if pmt.to_python(fn_time) is not None: self.message_port_pub(pmt.intern("fn_time_out"), fn_time_msg) +class dict_toggle_sign(gr.basic_block): + def __init__(self): # only default arguments here + gr.basic_block.__init__(self, + name='Change sign of elts in dict', + in_sig=[], + out_sig=[] + ) + self.message_port_register_in(pmt.intern("dict_in")) + self.message_port_register_out(pmt.intern("dict_out")) + self.set_msg_handler(pmt.intern("dict_in"), self.change_sign) + + def change_sign(self, msg): + if pmt.is_dict(msg): + d = pmt.to_python(msg) + for key, value in d.items(): + d[key] *= -1 + self.message_port_pub(pmt.intern("dict_out"), pmt.to_pmt(d)) + class radio_if(gr.top_block): # PHY specific variables rx_freq = 935e6 tx_freq = 890e6 + osr = 4 # Application state flags trx_started = False @@ -75,8 +96,10 @@ class radio_if(gr.top_block): print("[i] Init Radio interface") # PHY specific variables + self.sample_rate = phy_sample_rate self.rx_gain = phy_rx_gain self.tx_gain = phy_tx_gain + self.ppm = phy_ppm gr.top_block.__init__(self, "GR-GSM TRX") @@ -97,14 +120,15 @@ class radio_if(gr.top_block): self.phy_src.set_bandwidth(650e3, 0) self.phy_src.set_gain(phy_rx_gain) - self.gsm_input = grgsm.gsm_input( - ppm = phy_ppm - int(phy_ppm), osr = 4, - fc = self.rx_freq, samp_rate_in = phy_sample_rate) + self.msg_to_tag_src = grgsm.msg_to_tag() - self.gsm_receiver = grgsm.receiver(4, ([0]), ([])) + self.rotator_src = grgsm.controlled_rotator_cc( + self.calc_phase_inc(self.rx_freq)) - self.gsm_clck_ctrl = grgsm.clock_offset_control( - self.rx_freq, phy_sample_rate, osr = 4) + self.lpf = filter.fir_filter_ccf(1, firdes.low_pass( + 1, phy_sample_rate, 125e3, 5e3, firdes.WIN_HAMMING, 6.76)) + + self.gsm_receiver = grgsm.receiver(self.osr, ([0]), ([])) self.ts_filter = grgsm.burst_timeslot_filter(0) self.ts_filter.set_policy(grgsm.FILTER_POLICY_DROP_ALL) @@ -112,10 +136,18 @@ class radio_if(gr.top_block): # Connections self.connect( (self.phy_src, 0), - (self.gsm_input, 0)) + (self.msg_to_tag_src, 0)) self.connect( - (self.gsm_input, 0), + (self.msg_to_tag_src, 0), + (self.rotator_src, 0)) + + self.connect( + (self.rotator_src, 0), + (self.lpf, 0)) + + self.connect( + (self.lpf, 0), (self.gsm_receiver, 0)) self.msg_connect( @@ -126,14 +158,6 @@ class radio_if(gr.top_block): (self.ts_filter, 'out'), (self.trx_burst_if, 'bursts')) - self.msg_connect( - (self.gsm_receiver, 'measurements'), - (self.gsm_clck_ctrl, 'measurements')) - - self.msg_connect( - (self.gsm_clck_ctrl, 'ctrl'), - (self.gsm_input, 'ctrl_in')) - # TX Path Definition self.phy_sink = uhd.usrp_sink(phy_args, @@ -156,12 +180,17 @@ class radio_if(gr.top_block): blocks.byte_t, 'packet_len') self.gmsk_mod = grgsm.gsm_gmsk_mod( - BT = 4, pulse_duration = 4, sps = 4) + BT = 0.3, pulse_duration = 4, sps = self.osr) self.burst_shaper = digital.burst_shaper_cc( (firdes.window(firdes.WIN_HANN, 16, 0)), 0, 20, False, "packet_len") + self.msg_to_tag_sink = grgsm.msg_to_tag() + + self.rotator_sink = grgsm.controlled_rotator_cc( + -self.calc_phase_inc(self.tx_freq)) + # Connections self.msg_connect( (self.trx_burst_if, 'bursts'), @@ -185,6 +214,14 @@ class radio_if(gr.top_block): self.connect( (self.burst_shaper, 0), + (self.msg_to_tag_sink, 0)) + + self.connect( + (self.msg_to_tag_sink, 0), + (self.rotator_sink, 0)) + + self.connect( + (self.rotator_sink, 0), (self.phy_sink, 0)) @@ -205,19 +242,46 @@ class radio_if(gr.top_block): (self.burst_to_fn_time, 'fn_time_out'), (self.tx_time_setter, 'fn_time')) + + # AFC (Automatic Frequency Correction) + self.gsm_clck_ctrl = grgsm.clock_offset_control( + self.rx_freq, phy_sample_rate, osr = self.osr) + + self.dict_toggle_sign = dict_toggle_sign() + + # Connections + self.msg_connect( + (self.gsm_receiver, 'measurements'), + (self.gsm_clck_ctrl, 'measurements')) + + self.msg_connect( + (self.gsm_clck_ctrl, 'ctrl'), + (self.msg_to_tag_src, 'msg')) + + self.msg_connect( + (self.gsm_clck_ctrl, 'ctrl'), + (self.dict_toggle_sign, 'dict_in')) + + self.msg_connect( + (self.dict_toggle_sign, 'dict_out'), + (self.msg_to_tag_sink, 'msg')) + def shutdown(self): print("[i] Shutdown Radio interface") self.stop() self.wait() + def calc_phase_inc(self, fc): + return self.ppm / 1.0e6 * 2 * pi * fc / self.sample_rate + def set_rx_freq(self, fc): self.phy_src.set_center_freq(fc, 0) - self.gsm_clck_ctrl.set_fc(fc) - self.gsm_input.set_fc(fc) + self.rotator_src.set_phase_inc(self.calc_phase_inc(fc)) self.rx_freq = fc def set_tx_freq(self, fc): self.phy_sink.set_center_freq(fc, 0) + self.rotator_sink.set_phase_inc(-self.calc_phase_inc(fc)) self.tx_freq = fc def set_rx_gain(self, gain): |