diff options
Diffstat (limited to 'host/utils/uhd_cal_tx_dc_offset.cpp')
| -rw-r--r-- | host/utils/uhd_cal_tx_dc_offset.cpp | 172 |
1 files changed, 113 insertions, 59 deletions
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); |