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-rw-r--r--host/utils/uhd_cal_tx_iq_balance.cpp169
1 files changed, 110 insertions, 59 deletions
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);