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-rw-r--r--host/utils/uhd_cal_tx_iq_balance.cpp243
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diff --git a/host/utils/uhd_cal_tx_iq_balance.cpp b/host/utils/uhd_cal_tx_iq_balance.cpp
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+//
+// 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 "usrp_cal_utils.hpp"
+#include <uhd/utils/thread_priority.hpp>
+#include <uhd/utils/safe_main.hpp>
+#include <uhd/utils/paths.hpp>
+#include <uhd/utils/algorithm.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 <complex>
+#include <ctime>
+
+namespace po = boost::program_options;
+
+/***********************************************************************
+ * Transmit thread
+ **********************************************************************/
+static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_freq, const double tx_wave_ampl){
+ 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<samp_type> 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);
+ wave_table table(tx_wave_ampl);
+
+ //fill buff and send until interrupted
+ while (not boost::this_thread::interruption_requested()){
+ for (size_t i = 0; i < buff.size(); i++){
+ buff[i] = table(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);
+}
+
+/***********************************************************************
+ * Tune RX and TX routine
+ **********************************************************************/
+static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double tx_lo_freq, const double rx_offset){
+ //tune the transmitter with no cordic
+ uhd::tune_request_t tx_tune_req(tx_lo_freq);
+ 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);
+
+ //tune the receiver
+ usrp->set_rx_freq(usrp->get_tx_freq() - rx_offset);
+
+ //wait for the LOs to become locked
+ boost::this_thread::sleep(boost::posix_time::milliseconds(50));
+ boost::system_time start = boost::get_system_time();
+ while (not usrp->get_tx_sensor("lo_locked").to_bool() or 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 TX and/or RX LO to lock");
+ }
+ }
+
+ return usrp->get_tx_freq();
+}
+
+/***********************************************************************
+ * Main
+ **********************************************************************/
+int UHD_SAFE_MAIN(int argc, char *argv[]){
+ std::string args;
+ double tx_wave_freq, tx_wave_ampl, rx_offset;
+ double freq_start, freq_stop, freq_step;
+ size_t nsamps;
+
+ po::options_description desc("Allowed options");
+ desc.add_options()
+ ("help", "help message")
+ ("verbose", "enable some verbose")
+ ("args", po::value<std::string>(&args)->default_value(""), "device address args [default = \"\"]")
+ ("tx_wave_freq", po::value<double>(&tx_wave_freq)->default_value(507.123e3), "Transmit wave frequency in Hz")
+ ("tx_wave_ampl", po::value<double>(&tx_wave_ampl)->default_value(0.7), "Transmit wave amplitude in counts")
+ ("rx_offset", po::value<double>(&rx_offset)->default_value(.9344e6), "RX LO offset from the TX LO in Hz")
+ ("freq_start", po::value<double>(&freq_start), "Frequency start in Hz (do not specify for default)")
+ ("freq_stop", po::value<double>(&freq_stop), "Frequency stop in Hz (do not specify for default)")
+ ("freq_step", po::value<double>(&freq_step)->default_value(default_freq_step), "Step size for LO sweep in Hz")
+ ("nsamps", po::value<size_t>(&nsamps)->default_value(default_num_samps), "Samples per data capture")
+ ;
+
+ 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 TX IQ Balance 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 antennas to cal
+ if (not uhd::has(usrp->get_rx_antennas(), "CAL") or not uhd::has(usrp->get_tx_antennas(), "CAL")){
+ throw std::runtime_error("This board does not have the CAL antenna option, cannot self-calibrate.");
+ }
+ usrp->set_rx_antenna("CAL");
+ usrp->set_tx_antenna("CAL");
+
+ //set optimum defaults
+ set_optimum_defaults(usrp);
+
+ //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, tx_wave_freq, tx_wave_ampl));
+
+ //re-usable buffer for samples
+ std::vector<samp_type> buff;
+
+ //store the results here
+ std::vector<result_t> results;
+
+ if (not vm.count("freq_start")) freq_start = usrp->get_tx_freq_range().start() + 50e6;
+ if (not vm.count("freq_stop")) freq_stop = usrp->get_tx_freq_range().stop() - 50e6;
+
+ for (double tx_lo_i = freq_start; tx_lo_i <= freq_stop; tx_lo_i += freq_step){
+ const double tx_lo = tune_rx_and_tx(usrp, tx_lo_i, rx_offset);
+
+ //frequency constants for this tune event
+ 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;
+
+ //capture initial uncorrected value
+ usrp->set_tx_iq_balance(0.0);
+ capture_samples(usrp, rx_stream, buff, nsamps);
+ const double initial_suppression = compute_tone_dbrms(buff, bb_tone_freq/actual_rx_rate) - compute_tone_dbrms(buff, bb_imag_freq/actual_rx_rate);
+
+ //bounds and results from searching
+ std::complex<double> best_correction;
+ double phase_corr_start = -.3, phase_corr_stop = .3, phase_corr_step;
+ double ampl_corr_start = -.3, ampl_corr_stop = .3, ampl_corr_step;
+ double best_suppression = 0, best_phase_corr = 0, best_ampl_corr = 0;
+
+ for (size_t i = 0; i < num_search_iters; i++){
+
+ phase_corr_step = (phase_corr_stop - phase_corr_start)/(num_search_steps-1);
+ ampl_corr_step = (ampl_corr_stop - ampl_corr_start)/(num_search_steps-1);
+
+ for (double phase_corr = phase_corr_start; phase_corr <= phase_corr_stop + phase_corr_step/2; phase_corr += phase_corr_step){
+ for (double ampl_corr = ampl_corr_start; ampl_corr <= ampl_corr_stop + ampl_corr_step/2; ampl_corr += ampl_corr_step){
+
+ const std::complex<double> correction(ampl_corr, phase_corr);
+ usrp->set_tx_iq_balance(correction);
+
+ //receive some samples
+ capture_samples(usrp, rx_stream, buff, nsamps);
+
+ 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);
+ const double suppression = tone_dbrms - imag_dbrms;
+
+ if (suppression > best_suppression){
+ best_correction = correction;
+ best_suppression = suppression;
+ best_phase_corr = phase_corr;
+ best_ampl_corr = ampl_corr;
+ }
+
+ }}
+
+ //std::cout << "best_phase_corr " << best_phase_corr << std::endl;
+ //std::cout << "best_ampl_corr " << best_ampl_corr << std::endl;
+ //std::cout << "best_suppression " << best_suppression << std::endl;
+
+ phase_corr_start = best_phase_corr - phase_corr_step;
+ phase_corr_stop = best_phase_corr + phase_corr_step;
+ ampl_corr_start = best_ampl_corr - ampl_corr_step;
+ ampl_corr_stop = best_ampl_corr + ampl_corr_step;
+ }
+
+ if (best_suppression > 30){ //most likely valid, keep result
+ result_t result;
+ result.freq = tx_lo;
+ result.real_corr = best_correction.real();
+ result.imag_corr = best_correction.imag();
+ result.best = best_suppression;
+ result.delta = best_suppression - initial_suppression;
+ results.push_back(result);
+ if (vm.count("verbose")){
+ std::cout << boost::format("TX IQ: %f MHz: best suppression %f dB, corrected %f dB") % (tx_lo/1e6) % result.best % result.delta << std::endl;
+ }
+ else std::cout << "." << std::flush;
+ }
+
+ }
+ std::cout << std::endl;
+
+ //stop the transmitter
+ threads.interrupt_all();
+ threads.join_all();
+
+ store_results(usrp, results, "TX", "tx", "iq");
+
+ return 0;
+}