diff options
-rw-r--r-- | host/utils/uhd_cal_rx_iq_balance.cpp | 160 | ||||
-rw-r--r-- | host/utils/uhd_cal_tx_dc_offset.cpp | 172 | ||||
-rw-r--r-- | host/utils/uhd_cal_tx_iq_balance.cpp | 169 | ||||
-rw-r--r-- | host/utils/usrp_cal_utils.hpp | 231 |
4 files changed, 483 insertions, 249 deletions
diff --git a/host/utils/uhd_cal_rx_iq_balance.cpp b/host/utils/uhd_cal_rx_iq_balance.cpp index 3188e02a0..2414ef007 100644 --- a/host/utils/uhd_cal_rx_iq_balance.cpp +++ b/host/utils/uhd_cal_rx_iq_balance.cpp @@ -1,5 +1,5 @@ // -// Copyright 2010,2012 Ettus Research LLC +// Copyright 2010,2012,2014 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 @@ -37,7 +37,8 @@ namespace po = boost::program_options; /*********************************************************************** * Transmit thread **********************************************************************/ -static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_ampl){ +static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_ampl) +{ uhd::set_thread_priority_safe(); //create a transmit streamer @@ -50,10 +51,10 @@ static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_amp std::vector<samp_type> buff(tx_stream->get_max_num_samps()*10); //fill buff and send until interrupted - while (not boost::this_thread::interruption_requested()){ - for (size_t i = 0; i < buff.size(); i++){ + while (not boost::this_thread::interruption_requested()) + { + for (size_t i = 0; i < buff.size(); i++) buff[i] = float(tx_wave_ampl); - } tx_stream->send(&buff.front(), buff.size(), md); } @@ -65,26 +66,34 @@ static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_amp /*********************************************************************** * Tune RX and TX routine **********************************************************************/ -static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double rx_lo_freq, const double tx_offset){ +static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double rx_lo_freq, const double tx_offset) +{ //tune the receiver with no cordic uhd::tune_request_t rx_tune_req(rx_lo_freq); rx_tune_req.dsp_freq_policy = uhd::tune_request_t::POLICY_MANUAL; rx_tune_req.dsp_freq = 0; usrp->set_rx_freq(rx_tune_req); - //tune the transmitter with no cordic - uhd::tune_request_t tx_tune_req(usrp->get_rx_freq() - tx_offset); + //tune the transmitter + double tx_freq = usrp->get_rx_freq() + tx_offset; + double min_fe_tx_freq = usrp->get_fe_tx_freq_range().start(); + double max_fe_tx_freq = usrp->get_fe_tx_freq_range().stop(); + uhd::tune_request_t tx_tune_req(tx_freq); tx_tune_req.dsp_freq_policy = uhd::tune_request_t::POLICY_MANUAL; tx_tune_req.dsp_freq = 0; + if (tx_freq < min_fe_tx_freq) + tx_tune_req.dsp_freq = tx_freq - min_fe_tx_freq; + else if (tx_freq > max_fe_tx_freq) + tx_tune_req.dsp_freq = tx_freq - max_fe_tx_freq; usrp->set_tx_freq(tx_tune_req); //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)){ + 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_rx_freq(); @@ -93,11 +102,13 @@ static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double rx_l /*********************************************************************** * Main **********************************************************************/ -int UHD_SAFE_MAIN(int argc, char *argv[]){ +int UHD_SAFE_MAIN(int argc, char *argv[]) +{ std::string args, subdev, serial; double tx_wave_ampl, tx_offset; double freq_start, freq_stop, freq_step; size_t nsamps; + double precision; po::options_description desc("Allowed options"); desc.add_options() @@ -110,7 +121,8 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ ("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") + ("nsamps", po::value<size_t>(&nsamps), "Samples per data capture") + ("precision", po::value<double>(&precision)->default_value(default_precision), "Correction precision (default=0.0001)") ; po::variables_map vm; @@ -130,6 +142,9 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ // Create a USRP device uhd::usrp::multi_usrp::sptr usrp = setup_usrp_for_cal(args, subdev, serial); + if (not vm.count("nsamps")) + nsamps = size_t(usrp->get_rx_rate() / default_fft_bin_size); + //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); @@ -144,11 +159,35 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ //store the results here std::vector<result_t> results; - if (not vm.count("freq_start")) freq_start = usrp->get_rx_freq_range().start() + 50e6; - if (not vm.count("freq_stop")) freq_stop = usrp->get_rx_freq_range().stop() - 50e6; + if (not vm.count("freq_start")) freq_start = usrp->get_fe_rx_freq_range().start(); + if (not vm.count("freq_stop")) freq_stop = usrp->get_fe_tx_freq_range().stop(); + + //check start and stop frequencies + if (freq_start < usrp->get_fe_rx_freq_range().start()) + { + std::cerr << "freq_start must be " << usrp->get_fe_rx_freq_range().start() << " or greater for this daughter board" << std::endl; + return EXIT_FAILURE; + } + if (freq_stop > usrp->get_fe_rx_freq_range().stop()) + { + std::cerr << "freq_stop must be " << usrp->get_fe_rx_freq_range().stop() << " or less for this daughter board" << std::endl; + return EXIT_FAILURE; + } + + //check tx_offset + double min_tx_offset = usrp->get_tx_freq_range().start() - usrp->get_fe_rx_freq_range().start(); + double max_tx_offset = usrp->get_tx_freq_range().stop() - usrp->get_fe_rx_freq_range().stop(); + if (tx_offset < min_tx_offset or tx_offset > max_tx_offset) + { + std::cerr << "tx_offset must be between " << min_tx_offset << " and " + << max_tx_offset << " for this daughter board" << std::endl; + return EXIT_FAILURE; + } + UHD_MSG(status) << boost::format("Calibration frequency range: %d MHz -> %d MHz") % (freq_start/1e6) % (freq_stop/1e6) << std::endl; - for (double rx_lo_i = freq_start; rx_lo_i <= freq_stop; rx_lo_i += freq_step){ + for (double rx_lo_i = freq_start; rx_lo_i <= freq_stop; rx_lo_i += freq_step) + { const double rx_lo = tune_rx_and_tx(usrp, rx_lo_i, tx_offset); //frequency constants for this tune event @@ -158,73 +197,78 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ const double bb_tone_freq = actual_tx_freq - actual_rx_freq; const double bb_imag_freq = -bb_tone_freq; - //capture initial uncorrected value + //reset RX IQ balance usrp->set_rx_iq_balance(0.0); + + //set optimal RX gain setting for this frequency + set_optimal_rx_gain(usrp, rx_stream); + + //capture initial uncorrected value 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_rx_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; + double phase_corr_start = -1.0; + double phase_corr_stop = 1.0; + double phase_corr_step = (phase_corr_stop - phase_corr_start)/(num_search_steps+1); + double ampl_corr_start = -1.0; + double ampl_corr_stop = 1.0; + double ampl_corr_step = (ampl_corr_stop - ampl_corr_start)/(num_search_steps+1); + double best_suppression = 0; + double best_phase_corr = 0; + double best_ampl_corr = 0; + while (phase_corr_step >= precision or ampl_corr_step >= precision) + { + for (double phase_corr = phase_corr_start + phase_corr_step; phase_corr <= phase_corr_stop - phase_corr_step; phase_corr += phase_corr_step) + { + for (double ampl_corr = ampl_corr_start + ampl_corr_step; ampl_corr <= ampl_corr_stop - ampl_corr_step; ampl_corr += ampl_corr_step) + { + const std::complex<double> correction(ampl_corr, phase_corr); + usrp->set_rx_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_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; + phase_corr_step = (phase_corr_stop - phase_corr_start)/(num_search_steps+1); ampl_corr_start = best_ampl_corr - ampl_corr_step; ampl_corr_stop = best_ampl_corr + ampl_corr_step; + ampl_corr_step = (ampl_corr_stop - ampl_corr_start)/(num_search_steps+1); } - if (best_suppression > 30){ //most likely valid, keep result + if (best_suppression > initial_suppression) //keep result + { result_t result; result.freq = rx_lo; - result.real_corr = best_correction.real(); - result.imag_corr = best_correction.imag(); + result.real_corr = best_ampl_corr; + result.imag_corr = best_phase_corr; result.best = best_suppression; result.delta = best_suppression - initial_suppression; results.push_back(result); - if (vm.count("verbose")){ + if (vm.count("verbose")) std::cout << boost::format("RX IQ: %f MHz: best suppression %f dB, corrected %f dB") % (rx_lo/1e6) % result.best % result.delta << std::endl; - } - else std::cout << "." << std::flush; + else + std::cout << "." << std::flush; } - } std::cout << std::endl; //stop the transmitter threads.interrupt_all(); + boost::this_thread::sleep(boost::posix_time::milliseconds(500)); //wait for threads to finish threads.join_all(); store_results(results, "RX", "rx", "iq", serial); diff --git a/host/utils/uhd_cal_tx_dc_offset.cpp b/host/utils/uhd_cal_tx_dc_offset.cpp index b5c5293f0..8aa505010 100644 --- a/host/utils/uhd_cal_tx_dc_offset.cpp +++ b/host/utils/uhd_cal_tx_dc_offset.cpp @@ -1,5 +1,5 @@ // -// Copyright 2010,2012 Ettus Research LLC +// Copyright 2010,2012,2014 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 @@ -35,9 +35,13 @@ 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){ +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(); + // set max TX gain + usrp->set_tx_gain(usrp->get_tx_gain_range().stop()); + //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); @@ -50,14 +54,14 @@ static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_fre //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); + 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++){ + 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); } @@ -69,7 +73,8 @@ static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_fre /*********************************************************************** * 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){ +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; @@ -77,15 +82,25 @@ static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double tx_l usrp->set_tx_freq(tx_tune_req); //tune the receiver - usrp->set_rx_freq(usrp->get_tx_freq() - rx_offset); + double rx_freq = usrp->get_tx_freq() - rx_offset; + double min_fe_rx_freq = usrp->get_fe_rx_freq_range().start(); + double max_fe_rx_freq = usrp->get_fe_rx_freq_range().stop(); + uhd::tune_request_t rx_tune_req(rx_freq); + rx_tune_req.dsp_freq_policy = uhd::tune_request_t::POLICY_MANUAL; + rx_tune_req.dsp_freq = 0; + if (rx_freq < min_fe_rx_freq) + rx_tune_req.dsp_freq = rx_freq - min_fe_rx_freq; + else if (rx_freq > max_fe_rx_freq) + rx_tune_req.dsp_freq = rx_freq - max_fe_rx_freq; + usrp->set_rx_freq(rx_tune_req); //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)){ + 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(); @@ -94,11 +109,13 @@ static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double tx_l /*********************************************************************** * Main **********************************************************************/ -int UHD_SAFE_MAIN(int argc, char *argv[]){ +int UHD_SAFE_MAIN(int argc, char *argv[]) +{ std::string args, subdev, serial; double tx_wave_freq, tx_wave_ampl, rx_offset; double freq_start, freq_stop, freq_step; size_t nsamps; + double precision; po::options_description desc("Allowed options"); desc.add_options() @@ -112,7 +129,8 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ ("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") + ("nsamps", po::value<size_t>(&nsamps), "Samples per data capture") + ("precision", po::value<double>(&precision)->default_value(default_precision), "Correction precision (default=0.0001)") ; po::variables_map vm; @@ -132,6 +150,9 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ // Create a USRP device uhd::usrp::multi_usrp::sptr usrp = setup_usrp_for_cal(args, subdev, serial); + if (not vm.count("nsamps")) + nsamps = size_t(usrp->get_rx_rate() / default_fft_bin_size); + //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); @@ -146,11 +167,38 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ //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; + if (not vm.count("freq_start")) freq_start = usrp->get_fe_tx_freq_range().start(); + if (not vm.count("freq_stop")) freq_stop = usrp->get_fe_tx_freq_range().stop(); + + //check start and stop frequencies + if (freq_start < usrp->get_fe_tx_freq_range().start()) + { + std::cerr << "freq_start must be " << usrp->get_fe_tx_freq_range().start() << " or greater for this daughter board" << std::endl; + return EXIT_FAILURE; + } + if (freq_stop > usrp->get_fe_tx_freq_range().stop()) + { + std::cerr << "freq_stop must be " << usrp->get_fe_tx_freq_range().stop() << " or less for this daughter board" << std::endl; + return EXIT_FAILURE; + } + + //check rx_offset + double min_rx_offset = usrp->get_rx_freq_range().start() - usrp->get_fe_tx_freq_range().start(); + double max_rx_offset = usrp->get_rx_freq_range().stop() - usrp->get_fe_tx_freq_range().stop(); + if (rx_offset < min_rx_offset or rx_offset > max_rx_offset) + { + std::cerr << "rx_offset must be between " << min_rx_offset << " and " + << max_rx_offset << " for this daughter board" << std::endl; + return EXIT_FAILURE; + } + UHD_MSG(status) << boost::format("Calibration frequency range: %d MHz -> %d MHz") % (freq_start/1e6) % (freq_stop/1e6) << std::endl; - for (double tx_lo_i = freq_start; tx_lo_i <= freq_stop; tx_lo_i += freq_step){ + //set RX gain + usrp->set_rx_gain(0); + + 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 @@ -159,69 +207,75 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ const double actual_rx_freq = usrp->get_rx_freq(); const double bb_dc_freq = actual_tx_freq - actual_rx_freq; - //capture initial uncorrected value + //reset TX DC offset usrp->set_tx_dc_offset(std::complex<double>(0, 0)); + + //capture initial uncorrected value capture_samples(usrp, rx_stream, buff, nsamps); const double initial_dc_dbrms = compute_tone_dbrms(buff, bb_dc_freq/actual_rx_rate); //bounds and results from searching - double dc_i_start = -.01, dc_i_stop = .01, dc_i_step; - double dc_q_start = -.01, dc_q_stop = .01, dc_q_step; - double lowest_offset = 0, best_dc_i = 0, best_dc_q = 0; - - for (size_t i = 0; i < num_search_iters; i++){ - - dc_i_step = (dc_i_stop - dc_i_start)/(num_search_steps-1); - dc_q_step = (dc_q_stop - dc_q_start)/(num_search_steps-1); - - for (double dc_i = dc_i_start; dc_i <= dc_i_stop + dc_i_step/2; dc_i += dc_i_step){ - for (double dc_q = dc_q_start; dc_q <= dc_q_stop + dc_q_step/2; dc_q += dc_q_step){ - - const std::complex<double> correction(dc_i, dc_q); - usrp->set_tx_dc_offset(correction); - - //receive some samples - capture_samples(usrp, rx_stream, buff, nsamps); - - const double dc_dbrms = compute_tone_dbrms(buff, bb_dc_freq/actual_rx_rate); - - if (dc_dbrms < lowest_offset){ - lowest_offset = dc_dbrms; - best_dc_i = dc_i; - best_dc_q = dc_q; + double i_corr_start = -1.0; + double i_corr_stop = 1.0; + double i_corr_step = (i_corr_stop - i_corr_start)/(num_search_steps+1); + double q_corr_start = -1.0; + double q_corr_stop = 1.0; + double q_corr_step= (q_corr_stop - q_corr_start)/(num_search_steps+1); + double best_dc_dbrms = initial_dc_dbrms; + double best_i_corr = 0; + double best_q_corr = 0; + while (i_corr_step >= precision or q_corr_step >= precision) + { + for (double i_corr = i_corr_start + i_corr_step; i_corr <= i_corr_stop - i_corr_step; i_corr += i_corr_step) + { + for (double q_corr = q_corr_start + q_corr_step; q_corr <= q_corr_stop - q_corr_step; q_corr += q_corr_step) + { + const std::complex<double> correction(i_corr, q_corr); + usrp->set_tx_dc_offset(correction); + + //receive some samples + capture_samples(usrp, rx_stream, buff, nsamps); + const double dc_dbrms = compute_tone_dbrms(buff, bb_dc_freq/actual_rx_rate); + + if (dc_dbrms < best_dc_dbrms) + { + best_dc_dbrms = dc_dbrms; + best_i_corr = i_corr; + best_q_corr = q_corr; + } } + } - }} - - //std::cout << "best_dc_i " << best_dc_i << std::endl; - //std::cout << "best_dc_q " << best_dc_q << std::endl; - //std::cout << "lowest_offset " << lowest_offset << std::endl; - - dc_i_start = best_dc_i - dc_i_step; - dc_i_stop = best_dc_i + dc_i_step; - dc_q_start = best_dc_q - dc_q_step; - dc_q_stop = best_dc_q + dc_q_step; + i_corr_start = best_i_corr - i_corr_step; + i_corr_stop = best_i_corr + i_corr_step; + i_corr_step = (i_corr_stop - i_corr_start)/(num_search_steps+1); + q_corr_start = best_q_corr - q_corr_step; + q_corr_stop = best_q_corr + q_corr_step; + q_corr_step = (q_corr_stop - q_corr_start)/(num_search_steps+1); } - if (lowest_offset < initial_dc_dbrms){ //most likely valid, keep result + if (best_dc_dbrms < initial_dc_dbrms) //keep result + { result_t result; result.freq = tx_lo; - result.real_corr = best_dc_i; - result.imag_corr = best_dc_q; - result.best = lowest_offset; - result.delta = initial_dc_dbrms - lowest_offset; + result.real_corr = best_i_corr; + result.imag_corr = best_q_corr; + result.best = best_dc_dbrms; + result.delta = initial_dc_dbrms - best_dc_dbrms; results.push_back(result); - if (vm.count("verbose")){ + if (vm.count("verbose")) std::cout << boost::format("TX DC: %f MHz: lowest offset %f dB, corrected %f dB") % (tx_lo/1e6) % result.best % result.delta << std::endl; - } - else std::cout << "." << std::flush; + else + std::cout << "." << std::flush; } } + std::cout << std::endl; //stop the transmitter threads.interrupt_all(); + boost::this_thread::sleep(boost::posix_time::milliseconds(500)); //wait for threads to finish threads.join_all(); store_results(results, "TX", "tx", "dc", serial); diff --git a/host/utils/uhd_cal_tx_iq_balance.cpp b/host/utils/uhd_cal_tx_iq_balance.cpp index 6461b3d71..5952cccc4 100644 --- a/host/utils/uhd_cal_tx_iq_balance.cpp +++ b/host/utils/uhd_cal_tx_iq_balance.cpp @@ -1,5 +1,5 @@ // -// Copyright 2010,2012 Ettus Research LLC +// Copyright 2010,2012,2014 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 @@ -31,9 +31,13 @@ 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){ +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(); + // set max TX gain + usrp->set_tx_gain(usrp->get_tx_gain_range().stop()); + //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); @@ -46,14 +50,14 @@ static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_fre //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); + 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++){ + 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); } @@ -65,7 +69,8 @@ static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_fre /*********************************************************************** * 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){ +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; @@ -73,15 +78,25 @@ static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double tx_l usrp->set_tx_freq(tx_tune_req); //tune the receiver - usrp->set_rx_freq(usrp->get_tx_freq() - rx_offset); + double rx_freq = usrp->get_tx_freq() - rx_offset; + double min_fe_rx_freq = usrp->get_fe_rx_freq_range().start(); + double max_fe_rx_freq = usrp->get_fe_rx_freq_range().stop(); + uhd::tune_request_t rx_tune_req(rx_freq); + rx_tune_req.dsp_freq_policy = uhd::tune_request_t::POLICY_MANUAL; + rx_tune_req.dsp_freq = 0; + if (rx_freq < min_fe_rx_freq) + rx_tune_req.dsp_freq = rx_freq - min_fe_rx_freq; + else if (rx_freq > max_fe_rx_freq) + rx_tune_req.dsp_freq = rx_freq - max_fe_rx_freq; + usrp->set_rx_freq(rx_tune_req); //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)){ + 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(); @@ -90,11 +105,13 @@ static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double tx_l /*********************************************************************** * Main **********************************************************************/ -int UHD_SAFE_MAIN(int argc, char *argv[]){ +int UHD_SAFE_MAIN(int argc, char *argv[]) +{ std::string args, subdev, serial; double tx_wave_freq, tx_wave_ampl, rx_offset; double freq_start, freq_stop, freq_step; size_t nsamps; + double precision; po::options_description desc("Allowed options"); desc.add_options() @@ -108,7 +125,8 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ ("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") + ("nsamps", po::value<size_t>(&nsamps), "Samples per data capture") + ("precision", po::value<double>(&precision)->default_value(default_precision), "Correction precision (default=0.0001)") ; po::variables_map vm; @@ -116,7 +134,8 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ po::notify(vm); //print the help message - if (vm.count("help")){ + 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 a transceiver daughterboard to self-calibrate.\n" @@ -128,6 +147,9 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ // Create a USRP device uhd::usrp::multi_usrp::sptr usrp = setup_usrp_for_cal(args, subdev, serial); + if (not vm.count("nsamps")) + nsamps = size_t(usrp->get_rx_rate() / default_fft_bin_size); + //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); @@ -142,11 +164,35 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ //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; + if (not vm.count("freq_start")) freq_start = usrp->get_fe_tx_freq_range().start(); + if (not vm.count("freq_stop")) freq_stop = usrp->get_fe_tx_freq_range().stop(); + + //check start and stop frequencies + if (freq_start < usrp->get_fe_tx_freq_range().start()) + { + std::cerr << "freq_start must be " << usrp->get_fe_tx_freq_range().start() << " or greater for this daughter board" << std::endl; + return EXIT_FAILURE; + } + if (freq_stop > usrp->get_fe_tx_freq_range().stop()) + { + std::cerr << "freq_stop must be " << usrp->get_fe_tx_freq_range().stop() << " or less for this daughter board" << std::endl; + return EXIT_FAILURE; + } + + //check rx_offset + double min_rx_offset = usrp->get_rx_freq_range().start() - usrp->get_fe_tx_freq_range().start(); + double max_rx_offset = usrp->get_rx_freq_range().stop() - usrp->get_fe_tx_freq_range().stop(); + if (rx_offset < min_rx_offset or rx_offset > max_rx_offset) + { + std::cerr << "rx_offset must be between " << min_rx_offset << " and " + << max_rx_offset << " for this daughter board" << std::endl; + return EXIT_FAILURE; + } + UHD_MSG(status) << boost::format("Calibration frequency range: %d MHz -> %d MHz") % (freq_start/1e6) % (freq_stop/1e6) << std::endl; - for (double tx_lo_i = freq_start; tx_lo_i <= freq_stop; tx_lo_i += freq_step){ + 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 @@ -156,73 +202,78 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){ 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 + //reset TX IQ balance usrp->set_tx_iq_balance(0.0); + + //set optimal RX gain setting for this frequency + set_optimal_rx_gain(usrp, rx_stream, tx_wave_freq); + + //capture initial uncorrected value 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; + double phase_corr_start = -1.0; + double phase_corr_stop = 1.0; + double phase_corr_step = (phase_corr_stop - phase_corr_start)/(num_search_steps+1); + double ampl_corr_start = -1.0; + double ampl_corr_stop = 1.0; + double ampl_corr_step = (ampl_corr_stop - ampl_corr_start)/(num_search_steps+1); + double best_suppression = 0; + double best_phase_corr = 0; + double best_ampl_corr = 0; + while (phase_corr_step >= precision or ampl_corr_step >= precision) + { + for (double phase_corr = phase_corr_start + phase_corr_step; phase_corr <= phase_corr_stop - phase_corr_step; phase_corr += phase_corr_step) + { + for (double ampl_corr = ampl_corr_start + ampl_corr_step; ampl_corr <= ampl_corr_stop - ampl_corr_step; 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_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; + phase_corr_step = (phase_corr_stop - phase_corr_start)/(num_search_steps+1); ampl_corr_start = best_ampl_corr - ampl_corr_step; ampl_corr_stop = best_ampl_corr + ampl_corr_step; + ampl_corr_step = (ampl_corr_stop - ampl_corr_start)/(num_search_steps+1); } - if (best_suppression > 30){ //most likely valid, keep result + if (best_suppression > initial_suppression) //keep result + { result_t result; result.freq = tx_lo; - result.real_corr = best_correction.real(); - result.imag_corr = best_correction.imag(); + result.real_corr = best_ampl_corr; + result.imag_corr = best_phase_corr; result.best = best_suppression; result.delta = best_suppression - initial_suppression; results.push_back(result); - if (vm.count("verbose")){ + 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; + else + std::cout << "." << std::flush; } - } std::cout << std::endl; //stop the transmitter threads.interrupt_all(); + boost::this_thread::sleep(boost::posix_time::milliseconds(500)); //wait for threads to finish threads.join_all(); store_results(results, "TX", "tx", "iq", serial); diff --git a/host/utils/usrp_cal_utils.hpp b/host/utils/usrp_cal_utils.hpp index 9e7f4c469..6673b6329 100644 --- a/host/utils/usrp_cal_utils.hpp +++ b/host/utils/usrp_cal_utils.hpp @@ -1,5 +1,5 @@ // -// Copyright 2011-2012 Ettus Research LLC +// Copyright 2011-2012,2014 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 @@ -41,82 +41,77 @@ typedef std::complex<float> samp_type; * Constants **********************************************************************/ static const double tau = 6.28318531; -static const size_t wave_table_len = 8192; +static const size_t wave_table_len = 65536; static const size_t num_search_steps = 5; -static const size_t num_search_iters = 7; +static const double default_precision = 0.0001; static const double default_freq_step = 7.3e6; -static const size_t default_num_samps = 10000; +static const size_t default_fft_bin_size = 1000; /*********************************************************************** * Set standard defaults for devices **********************************************************************/ -static inline void set_optimum_defaults(uhd::usrp::multi_usrp::sptr usrp){ +static inline void set_optimum_defaults(uhd::usrp::multi_usrp::sptr usrp) +{ uhd::property_tree::sptr tree = usrp->get_device()->get_tree(); // Will work on 1st subdev, top-level must make sure it's the right one uhd::usrp::subdev_spec_t subdev_spec = usrp->get_rx_subdev_spec(); const uhd::fs_path mb_path = "/mboards/0"; const std::string mb_name = tree->access<std::string>(mb_path / "name").get(); - if (mb_name.find("USRP2") != std::string::npos or mb_name.find("N200") != std::string::npos or mb_name.find("N210") != std::string::npos or mb_name.find("X300") != std::string::npos or mb_name.find("X310") != std::string::npos){ + if (mb_name.find("USRP2") != std::string::npos or + mb_name.find("N200") != std::string::npos or + mb_name.find("N210") != std::string::npos or + mb_name.find("X300") != std::string::npos or + mb_name.find("X310") != std::string::npos) + { usrp->set_tx_rate(12.5e6); usrp->set_rx_rate(12.5e6); } - else if (mb_name.find("B100") != std::string::npos){ + else if (mb_name.find("B100") != std::string::npos) + { usrp->set_tx_rate(4e6); usrp->set_rx_rate(4e6); } - else if (mb_name.find("E100") != std::string::npos or mb_name.find("E110") != std::string::npos){ + else if (mb_name.find("E100") != std::string::npos or mb_name.find("E110") != std::string::npos) + { usrp->set_tx_rate(4e6); usrp->set_rx_rate(8e6); } - else{ - throw std::runtime_error("self-calibration is not supported for this hardware"); + else + { + throw std::runtime_error("self-calibration is not supported for this device"); } const uhd::fs_path tx_fe_path = "/mboards/0/dboards/" + subdev_spec[0].db_name + "/tx_frontends/0"; const std::string tx_name = tree->access<std::string>(tx_fe_path / "name").get(); - if (tx_name.find("WBX") != std::string::npos){ - usrp->set_tx_gain(0); - } - else if (tx_name.find("SBX") != std::string::npos){ - usrp->set_tx_gain(0); - } - else if (tx_name.find("CBX") != std::string::npos){ - usrp->set_tx_gain(0); - } - else if (tx_name.find("RFX") != std::string::npos){ - usrp->set_tx_gain(0); - } - else{ - throw std::runtime_error("self-calibration is not supported for this hardware"); + if (tx_name.find("WBX") == std::string::npos and + tx_name.find("SBX") == std::string::npos and + tx_name.find("CBX") == std::string::npos and + tx_name.find("RFX") == std::string::npos + ) + { + throw std::runtime_error("self-calibration is not supported for this TX dboard"); } + usrp->set_tx_gain(0); const uhd::fs_path rx_fe_path = "/mboards/0/dboards/" + subdev_spec[0].db_name + "/rx_frontends/0"; const std::string rx_name = tree->access<std::string>(rx_fe_path / "name").get(); - if (rx_name.find("WBX") != std::string::npos){ - usrp->set_rx_gain(25); - } - else if (rx_name.find("SBX") != std::string::npos){ - usrp->set_rx_gain(25); + if (rx_name.find("WBX") == std::string::npos and + rx_name.find("SBX") == std::string::npos and + rx_name.find("CBX") == std::string::npos and + rx_name.find("RFX") == std::string::npos + ) + { + throw std::runtime_error("self-calibration is not supported for this RX dboard"); } - else if (rx_name.find("CBX") != std::string::npos){ - usrp->set_rx_gain(25); - } - else if (rx_name.find("RFX") != std::string::npos){ - usrp->set_rx_gain(25); - } - else{ - throw std::runtime_error("self-calibration is not supported for this hardware"); - } - + usrp->set_rx_gain(0); } /*********************************************************************** * Check for empty serial **********************************************************************/ -void check_for_empty_serial( - uhd::usrp::multi_usrp::sptr usrp -){ +void check_for_empty_serial(uhd::usrp::multi_usrp::sptr usrp) +{ // Will work on 1st subdev, top-level must make sure it's the right one uhd::usrp::subdev_spec_t subdev_spec = usrp->get_rx_subdev_spec(); @@ -127,22 +122,25 @@ void check_for_empty_serial( const uhd::usrp::dboard_eeprom_t db_eeprom = tree->access<uhd::usrp::dboard_eeprom_t>(db_path).get(); std::string error_string = "This dboard has no serial!\n\nPlease see the Calibration documentation for details on how to fix this."; - if (db_eeprom.serial.empty()) throw std::runtime_error(error_string); + if (db_eeprom.serial.empty()) + throw std::runtime_error(error_string); } /*********************************************************************** * Sinusoid wave table **********************************************************************/ -class wave_table{ +class wave_table +{ public: - wave_table(const double ampl){ + wave_table(const double ampl) + { _table.resize(wave_table_len); - for (size_t i = 0; i < wave_table_len; i++){ + for (size_t i = 0; i < wave_table_len; i++) _table[i] = samp_type(std::polar(ampl, (tau*i)/wave_table_len)); - } } - inline samp_type operator()(const size_t index) const{ + inline samp_type operator()(const size_t index) const + { return _table[index % wave_table_len]; } @@ -154,15 +152,14 @@ private: * Compute power of a tone **********************************************************************/ static inline double compute_tone_dbrms( - const std::vector<samp_type > &samples, - const double freq //freq is fractional -){ + const std::vector<samp_type> &samples, + const double freq) //freq is fractional +{ //shift the samples so the tone at freq is down at DC //and average the samples to measure the DC component samp_type average = 0; - for (size_t i = 0; i < samples.size(); i++){ + for (size_t i = 0; i < samples.size(); i++) average += samp_type(std::polar(1.0, -freq*tau*i)) * samples[i]; - } return 20*std::log10(std::abs(average/float(samples.size()))); } @@ -171,8 +168,8 @@ static inline double compute_tone_dbrms( * Write a dat file **********************************************************************/ static inline void write_samples_to_file( - const std::vector<samp_type > &samples, const std::string &file -){ + const std::vector<samp_type > &samples, const std::string &file) +{ std::ofstream outfile(file.c_str(), std::ofstream::binary); outfile.write((const char*)&samples.front(), samples.size()*sizeof(samp_type)); outfile.close(); @@ -184,8 +181,8 @@ static inline void write_samples_to_file( **********************************************************************/ static std::string get_serial( uhd::usrp::multi_usrp::sptr usrp, - const std::string &tx_rx -){ + const std::string &tx_rx) +{ uhd::property_tree::sptr tree = usrp->get_device()->get_tree(); // Will work on 1st subdev, top-level must make sure it's the right one uhd::usrp::subdev_spec_t subdev_spec = usrp->get_rx_subdev_spec(); @@ -202,17 +199,16 @@ static void store_results( const std::string &XX, // "TX" or "RX" const std::string &xx, // "tx" or "rx" const std::string &what, // Type of test, e.g. "iq", - const std::string &serial -){ + const std::string &serial) +{ //make the calibration file path fs::path cal_data_path = fs::path(uhd::get_app_path()) / ".uhd"; fs::create_directory(cal_data_path); cal_data_path = cal_data_path / "cal"; fs::create_directory(cal_data_path); cal_data_path = cal_data_path / str(boost::format("%s_%s_cal_v0.2_%s.csv") % xx % what % serial); - if (fs::exists(cal_data_path)){ + if (fs::exists(cal_data_path)) fs::rename(cal_data_path, cal_data_path.string() + str(boost::format(".%d") % time(NULL))); - } //fill the calibration file std::ofstream cal_data(cal_data_path.string().c_str()); @@ -223,7 +219,8 @@ static void store_results( cal_data << boost::format("DATA STARTS HERE\n"); cal_data << "lo_frequency, correction_real, correction_imag, measured, delta\n"; - for (size_t i = 0; i < results.size(); i++){ + for (size_t i = 0; i < results.size(); i++) + { cal_data << results[i].freq << ", " << results[i].real_corr << ", " @@ -243,31 +240,50 @@ static void capture_samples( uhd::usrp::multi_usrp::sptr usrp, uhd::rx_streamer::sptr rx_stream, std::vector<samp_type > &buff, - const size_t nsamps_requested -){ + const size_t nsamps_requested) +{ buff.resize(nsamps_requested); uhd::rx_metadata_t md; + // Right after the stream is started, there will be transient data. + // That transient data is discarded and only "good" samples are returned. + size_t nsamps_to_discard = usrp->get_rx_rate() * 0.001; // 1ms to be discarded + std::vector<samp_type> discard_buff(nsamps_to_discard); + uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE); - stream_cmd.num_samps = buff.size(); + stream_cmd.num_samps = buff.size() + nsamps_to_discard; stream_cmd.stream_now = true; usrp->issue_stream_cmd(stream_cmd); - const size_t num_rx_samps = rx_stream->recv(&buff.front(), buff.size(), md); + size_t num_rx_samps = 0; + + // Discard the transient samples. + rx_stream->recv(&discard_buff.front(), discard_buff.size(), md); + if (md.error_code != uhd::rx_metadata_t::ERROR_CODE_NONE) + { + throw std::runtime_error(str(boost::format( + "Receiver error: %s" + ) % md.strerror())); + } + + // Now capture the data we want + 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){ + if (md.error_code != uhd::rx_metadata_t::ERROR_CODE_NONE) + { throw std::runtime_error(str(boost::format( "Receiver error: %s" ) % md.strerror())); } + //we can live if all the data didnt come in - if (num_rx_samps > buff.size()/2){ + if (num_rx_samps > buff.size()/2) + { buff.resize(num_rx_samps); return; } - if (num_rx_samps != buff.size()){ + if (num_rx_samps != buff.size()) throw std::runtime_error("did not get all the samples requested"); - } } /*********************************************************************** @@ -280,7 +296,8 @@ static uhd::usrp::multi_usrp::sptr setup_usrp_for_cal(std::string &args, std::st uhd::usrp::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args); // Configure subdev - if (!subdev.empty()) { + if (!subdev.empty()) + { usrp->set_tx_subdev_spec(subdev); usrp->set_rx_subdev_spec(subdev); } @@ -289,9 +306,8 @@ static uhd::usrp::multi_usrp::sptr setup_usrp_for_cal(std::string &args, std::st UHD_MSG(status) << "Daughterboard serial: " << serial << std::endl; //set the antennas to cal - if (not uhd::has(usrp->get_rx_antennas(), "CAL") or not uhd::has(usrp->get_tx_antennas(), "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"); @@ -304,3 +320,72 @@ static uhd::usrp::multi_usrp::sptr setup_usrp_for_cal(std::string &args, std::st return usrp; } +/*********************************************************************** + * Function to find optimal RX gain setting (for the current frequency) + **********************************************************************/ +UHD_INLINE void set_optimal_rx_gain( + uhd::usrp::multi_usrp::sptr usrp, + uhd::rx_streamer::sptr rx_stream, + double wave_freq = 0.0) +{ + const double gain_step = 3.0; + const double gain_compression_threshold = gain_step * 0.5; + 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 - actual_rx_freq + wave_freq; + const size_t nsamps = size_t(actual_rx_rate / default_fft_bin_size); + + std::vector<samp_type> buff(nsamps); + uhd::gain_range_t rx_gain_range = usrp->get_rx_gain_range(); + double rx_gain = rx_gain_range.start() + gain_step; + double curr_dbrms = 0.0; + double prev_dbrms = 0.0; + double delta = 0.0; + + // No sense in setting the gain where this is no gain range + if (rx_gain_range.stop() - rx_gain_range.start() < gain_step) + return; + + // The algorithm below cycles through the RX gain range + // looking for the point where the signal begins to get + // clipped and the gain begins to be compressed. It does + // this by looking for the gain setting where the increase + // in the tone is less than the gain step by more than the + // gain compression threshold (curr - prev < gain - threshold). + + // Initialize prev_dbrms value + usrp->set_rx_gain(rx_gain); + capture_samples(usrp, rx_stream, buff, nsamps); + prev_dbrms = compute_tone_dbrms(buff, bb_tone_freq/actual_rx_rate); + rx_gain += gain_step; + + // Find RX gain where signal begins to clip + while (rx_gain <= rx_gain_range.stop()) + { + usrp->set_rx_gain(rx_gain); + capture_samples(usrp, rx_stream, buff, nsamps); + curr_dbrms = compute_tone_dbrms(buff, bb_tone_freq/actual_rx_rate); + delta = curr_dbrms - prev_dbrms; + + // check if the gain is compressed beyone the threshold + if (delta < gain_step - gain_compression_threshold) + break; // if so, we are done + + prev_dbrms = curr_dbrms; + rx_gain += gain_step; + } + + // The rx_gain value at this point is the gain setting where clipping + // occurs or the gain setting that is just beyond the gain range. + // The gain is reduced by 2 steps to make sure it is within the range and + // under the point where it is clipped with enough room to make adjustments. + rx_gain -= 2 * gain_step; + + // Make sure the gain is within the range. + rx_gain = rx_gain_range.clip(rx_gain); + + // Finally, set the gain. + usrp->set_rx_gain(rx_gain); +} + |