| #!/usr/bin/env python2 |
| # -*- coding: utf-8 -*- |
| |
| # GR-GSM based transceiver |
| # Follow graph implementation |
| # |
| # (C) 2016-2017 by Vadim Yanitskiy <axilirator@gmail.com> |
| # (C) 2017 by Piotr Krysik <ptrkrysik@gmail.com> |
| # |
| # All Rights Reserved |
| # |
| # This program is free software; you can redistribute it and/or modify |
| # it under the terms of the GNU General Public License as published by |
| # the Free Software Foundation; either version 2 of the License, or |
| # (at your option) any later version. |
| # |
| # This program is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| # GNU General Public License for more details. |
| # |
| # You should have received a copy of the GNU General Public License along |
| # with this program; if not, write to the Free Software Foundation, Inc., |
| # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| |
| import pmt |
| import time |
| import grgsm |
| |
| from math import pi |
| |
| 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 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 |
| |
| # GSM timings (in microseconds [uS]) |
| # One timeslot duration is 576.9 μs = 15/26 ms, |
| # or 156.25 symbol periods (a symbol period is 48/13 μs) |
| GSM_SYM_PERIOD_uS = 48.0 / 13.0 |
| GSM_TS_PERIOD_uS = GSM_SYM_PERIOD_uS * 156.25 |
| GSM_UL_DL_SHIFT_uS = -(GSM_TS_PERIOD_uS * 3) |
| |
| # FIXME: shall be measured (automatically?) for |
| # particular device and particular clock rate. |
| # The current value is measured for USRP B2X0 at 26e6. |
| delay_correction = (285.616 + 2 * GSM_SYM_PERIOD_uS) * 1e-6 |
| |
| def __init__(self, phy_args, phy_sample_rate, |
| phy_rx_gain, phy_tx_gain, phy_ppm, |
| phy_rx_antenna, phy_tx_antenna, |
| trx_bind_addr, trx_remote_addr, |
| trx_base_port): |
| |
| print("[i] Init Radio interface (L:%s:%u <-> R:%s:%u)" |
| % (trx_bind_addr, trx_base_port + 2, |
| trx_remote_addr, trx_base_port + 102)) |
| |
| # 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") |
| |
| # TRX Burst Interface |
| self.trx_burst_if = grgsm.trx_burst_if( |
| trx_bind_addr, trx_remote_addr, |
| str(trx_base_port)) |
| |
| # RX path definition |
| self.phy_src = uhd.usrp_source(phy_args, |
| uhd.stream_args(cpu_format="fc32", |
| channels=range(1))) |
| |
| self.phy_src.set_clock_rate(26e6, uhd.ALL_MBOARDS) |
| self.phy_src.set_center_freq(self.rx_freq, 0) |
| self.phy_src.set_antenna(phy_rx_antenna, 0) |
| self.phy_src.set_samp_rate(phy_sample_rate) |
| self.phy_src.set_bandwidth(650e3, 0) |
| self.phy_src.set_gain(phy_rx_gain) |
| |
| self.msg_to_tag_src = grgsm.msg_to_tag() |
| |
| self.rotator_src = grgsm.controlled_rotator_cc( |
| self.calc_phase_inc(self.rx_freq)) |
| |
| 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) |
| |
| # Connections |
| self.connect( |
| (self.phy_src, 0), |
| (self.msg_to_tag_src, 0)) |
| |
| self.connect( |
| (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( |
| (self.gsm_receiver, 'C0'), |
| (self.ts_filter, 'in')) |
| |
| self.msg_connect( |
| (self.ts_filter, 'out'), |
| (self.trx_burst_if, 'bursts')) |
| |
| |
| # TX Path Definition |
| self.phy_sink = uhd.usrp_sink(phy_args, |
| uhd.stream_args(cpu_format="fc32", |
| channels=range(1)), "packet_len") |
| |
| self.phy_sink.set_clock_rate(26e6, uhd.ALL_MBOARDS) |
| self.phy_sink.set_antenna(phy_tx_antenna, 0) |
| self.phy_sink.set_samp_rate(phy_sample_rate) |
| self.phy_sink.set_center_freq(self.tx_freq, 0) |
| self.phy_sink.set_gain(self.tx_gain) |
| |
| self.tx_time_setter = grgsm.txtime_setter( |
| 0xffffffff, 0, 0, 0, 0, 0, |
| self.delay_correction + self.GSM_UL_DL_SHIFT_uS * 1e-6) |
| |
| self.tx_burst_proc = grgsm.preprocess_tx_burst() |
| |
| self.pdu_to_tagged_stream = blocks.pdu_to_tagged_stream( |
| blocks.byte_t, 'packet_len') |
| |
| self.gmsk_mod = grgsm.gsm_gmsk_mod( |
| 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'), |
| (self.tx_time_setter, 'bursts_in')) |
| |
| self.msg_connect( |
| (self.tx_time_setter, 'bursts_out'), |
| (self.tx_burst_proc, 'bursts_in')) |
| |
| self.msg_connect( |
| (self.tx_burst_proc, 'bursts_out'), |
| (self.pdu_to_tagged_stream, 'pdus')) |
| |
| self.connect( |
| (self.pdu_to_tagged_stream, 0), |
| (self.gmsk_mod, 0)) |
| |
| self.connect( |
| (self.gmsk_mod, 0), |
| (self.burst_shaper, 0)) |
| |
| 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)) |
| |
| |
| # RX & TX synchronization |
| self.bt_filter = grgsm.burst_type_filter([3]) |
| self.burst_to_fn_time = grgsm.burst_to_fn_time() |
| |
| # Connections |
| self.msg_connect( |
| (self.gsm_receiver, 'C0'), |
| (self.bt_filter, 'bursts_in')) |
| |
| self.msg_connect( |
| (self.bt_filter, 'bursts_out'), |
| (self.burst_to_fn_time, 'bursts_in')) |
| |
| self.msg_connect( |
| (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')) |
| |
| |
| # Some UHD devices (such as UmTRX) do start the clock |
| # not from 0, so it's required to reset it manually. |
| # Resetting UHD source will also affect the sink. |
| self.phy_src.set_time_now(uhd.time_spec(0.0)) |
| |
| 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.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): |
| self.phy_src.set_gain(gain, 0) |
| self.rx_gain = gain |
| |
| def set_tx_gain(self, gain): |
| self.phy_sink.set_gain(gain, 0) |
| self.tx_gain = gain |
| |
| def set_ta(self, ta): |
| print("[i] Setting TA value %d" % ta) |
| advance_time_sec = ta * self.GSM_SYM_PERIOD_uS * 1e-6 |
| self.tx_time_setter.set_timing_advance(advance_time_sec) |