diff options
| -rw-r--r-- | host/utils/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | host/utils/usrp_gen_db_cal_table.cpp | 243 |
2 files changed, 244 insertions, 0 deletions
diff --git a/host/utils/CMakeLists.txt b/host/utils/CMakeLists.txt index 1a0396ad3..796fdf96f 100644 --- a/host/utils/CMakeLists.txt +++ b/host/utils/CMakeLists.txt @@ -37,6 +37,7 @@ ENDFOREACH(util_source) SET(util_share_sources usrp_burn_db_eeprom.cpp usrp_burn_mb_eeprom.cpp + usrp_gen_db_cal_table.cpp ) IF(ENABLE_USB) diff --git a/host/utils/usrp_gen_db_cal_table.cpp b/host/utils/usrp_gen_db_cal_table.cpp new file mode 100644 index 000000000..8fb3be020 --- /dev/null +++ b/host/utils/usrp_gen_db_cal_table.cpp @@ -0,0 +1,243 @@ +// +// Copyright 2010 Ettus Research LLC +// +// 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 3 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, see <http://www.gnu.org/licenses/>. +// + +#include <uhd/utils/thread_priority.hpp> +#include <uhd/utils/safe_main.hpp> +#include <uhd/usrp/multi_usrp.hpp> +#include <boost/program_options.hpp> +#include <boost/format.hpp> +#include <boost/thread/thread.hpp> +#include <boost/math/special_functions/round.hpp> +#include <iostream> +#include <fstream> +#include <complex> +#include <cmath> + +namespace po = boost::program_options; + +/*********************************************************************** + * Constants + **********************************************************************/ +static const double e = 2.71828183; +static const double tau = 6.28318531; +static const double alpha = 0.0001; //very tight iir filter +static const size_t wave_table_len = 8192; +static const float ampl = 0.7; //transmitted wave amplitude +static const double tx_wave_freq = 507.123e3; //freq of tx sine wave in Hz + +/*********************************************************************** + * Sinusoid wave table + **********************************************************************/ +static std::vector<std::complex<float> > gen_table(void){ + std::vector<std::complex<float> > wave_table(wave_table_len); + std::vector<double> real_wave_table(wave_table_len); + for (size_t i = 0; i < wave_table_len; i++) + real_wave_table[i] = std::sin((tau*i)/wave_table_len); + + //compute i and q pairs with 90% offset and scale to amplitude + for (size_t i = 0; i < wave_table_len; i++){ + const size_t q = (i+(3*wave_table_len)/4)%wave_table_len; + wave_table[i] = std::complex<float>(ampl*real_wave_table[i], ampl*real_wave_table[q]); + } + + return wave_table; +} + +static std::complex<float> wave_table_lookup(size_t &index){ + static const std::vector<std::complex<float> > wave_table = gen_table(); + index %= wave_table_len; + return wave_table[index]; +} + +/*********************************************************************** + * Compute power of a tone + **********************************************************************/ +static double compute_tone_dbrms( + const std::vector<std::complex<float> > &samples, + const double freq //freq is fractional +){ + //shift the samples so the tone at freq is down at DC + std::vector<std::complex<double> > shifted(samples.size()); + for (size_t i = 0; i < shifted.size(); i++){ + shifted[i] = std::complex<double>(samples[i]) * std::pow(e, std::complex<double>(0, -freq*tau*i)); + } + + std::vector<std::complex<float> > buff(shifted.size()); + for (size_t i = 0; i < buff.size(); i++) buff[i] = shifted[i]; + std::ofstream outfile("/home/jblum/Desktop/gen.dat", std::ofstream::binary); + outfile.write((const char*)&buff.front(), buff.size() * 8); + + //filter the samples with a narrow low pass + std::complex<double> iir_output = 0, iir_last = 0; + double output = 0; + for (size_t i = 0; i < shifted.size(); i++){ + iir_output = alpha * shifted[i] + (1-alpha)*iir_last; + iir_last = iir_output; + output += std::abs(iir_output); + } + + return 20*std::log10(output/shifted.size()); +} + +/*********************************************************************** + * Transmit thread + **********************************************************************/ +static void tx_thread(uhd::usrp::multi_usrp::sptr usrp){ + uhd::set_thread_priority_safe(); + + //create a transmit streamer + uhd::stream_args_t stream_args("fc32"); //complex floats + uhd::tx_streamer::sptr tx_stream = usrp->get_tx_stream(stream_args); + + //setup variables and allocate buffer + uhd::tx_metadata_t md; + md.has_time_spec = false; + std::vector<std::complex<float> > buff(tx_stream->get_max_num_samps()*10); + + //values for the wave table lookup + size_t index = 0; + const double tx_rate = usrp->get_tx_rate(); + const size_t step = boost::math::iround(wave_table_len * tx_wave_freq/tx_rate); + + //fill buff and send until interrupted + while (not boost::this_thread::interruption_requested()){ + for (size_t i = 0; i < buff.size(); i++){ + buff[i] = wave_table_lookup(index); + index += step; + } + tx_stream->send(&buff.front(), buff.size(), md); + } + + //send a mini EOB packet + md.end_of_burst = true; + tx_stream->send("", 0, md); +} + +/*********************************************************************** + * Main + **********************************************************************/ +int UHD_SAFE_MAIN(int argc, char *argv[]){ + std::string args; + double rate; + + po::options_description desc("Allowed options"); + desc.add_options() + ("help", "help message") + ("args", po::value<std::string>(&args)->default_value(""), "device address args [default = \"\"]") + ("rate", po::value<double>(&rate)->default_value(12.5e6), "RX and TX sample rate in Hz") + ; + + po::variables_map vm; + po::store(po::parse_command_line(argc, argv, desc), vm); + po::notify(vm); + + //print the help message + if (vm.count("help")){ + std::cout << boost::format("USRP Generate Daughterboard Calibration Table %s") % desc << std::endl; + std::cout << + "This application measures leakage between RX and TX on an XCVR daughterboard to self-calibrate.\n" + << std::endl; + return ~0; + } + + //create a usrp device + std::cout << std::endl; + std::cout << boost::format("Creating the usrp device with: %s...") % args << std::endl; + uhd::usrp::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args); + + //set the sample rates + usrp->set_rx_rate(rate); + usrp->set_tx_rate(rate); + + //tune the transmitter with no cordic + uhd::tune_request_t tx_tune_req(2.155e9); + tx_tune_req.dsp_freq_policy = uhd::tune_request_t::POLICY_MANUAL; + tx_tune_req.dsp_freq = 0; + usrp->set_tx_freq(tx_tune_req); + { + boost::system_time start = boost::get_system_time(); + while (not usrp->get_tx_sensor("lo_locked").to_bool()){ + if (boost::get_system_time() > start + boost::posix_time::milliseconds(100)){ + throw std::runtime_error("timed out waiting for TX LO to lock"); + } + } + } + + //tune the receiver + usrp->set_rx_freq(2.155e9 - .9344e6); + { + boost::system_time start = boost::get_system_time(); + while (not usrp->get_rx_sensor("lo_locked").to_bool()){ + if (boost::get_system_time() > start + boost::posix_time::milliseconds(100)){ + throw std::runtime_error("timed out waiting for RX LO to lock"); + } + } + } + + //set max receiver gain + usrp->set_rx_gain(usrp->get_rx_gain_range().stop()); + + //create a receive streamer + uhd::stream_args_t stream_args("fc32"); //complex floats + uhd::rx_streamer::sptr rx_stream = usrp->get_rx_stream(stream_args); + + //create a transmitter thread + boost::thread_group threads; + threads.create_thread(boost::bind(&tx_thread, usrp)); + + //receive some samples + std::vector<std::complex<float> > buff(100000); + usrp->set_time_now(uhd::time_spec_t(0.0)); + uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE); + stream_cmd.num_samps = buff.size(); + stream_cmd.stream_now = false; + stream_cmd.time_spec = uhd::time_spec_t(0.1); + usrp->issue_stream_cmd(stream_cmd); + uhd::rx_metadata_t md; + const size_t num_rx_samps = rx_stream->recv(&buff.front(), buff.size(), md); + + //validate the received data + if (md.error_code != uhd::rx_metadata_t::ERROR_CODE_NONE){ + throw std::runtime_error(str(boost::format( + "Unexpected error code 0x%x" + ) % md.error_code)); + } + if (num_rx_samps != buff.size()){ + throw std::runtime_error("did not get all the samples requested"); + } + + //stop the transmitter + threads.interrupt_all(); + threads.join_all(); + + const double actual_rx_rate = usrp->get_rx_rate(); + const double actual_tx_freq = usrp->get_tx_freq(); + const double actual_rx_freq = usrp->get_rx_freq(); + const double bb_tone_freq = actual_tx_freq + tx_wave_freq - actual_rx_freq; + const double bb_imag_freq = actual_tx_freq - tx_wave_freq - actual_rx_freq; + + const double tone_dbrms = compute_tone_dbrms(buff, bb_tone_freq/actual_rx_rate); + const double imag_dbrms = compute_tone_dbrms(buff, bb_imag_freq/actual_rx_rate); + + std::cout << "bb_tone_freq " << bb_tone_freq << std::endl; + std::cout << "bb_imag_freq " << bb_imag_freq << std::endl; + std::cout << "tone_dbrms " << tone_dbrms << std::endl; + std::cout << "imag_dbrms " << imag_dbrms << std::endl; + std::cout << "supression " << (tone_dbrms - imag_dbrms) << std::endl; + + return 0; +} |