/***********************************************************************
* Main
**********************************************************************/
int UHD_SAFE_MAIN(int argc, char *argv[]){
std::string args;
double tx_wave_ampl, tx_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_ampl", po::value<double>(&tx_wave_ampl)->default_value(0.7), "Transmit wave amplitude in counts")
("tx_offset", po::value<double>(&tx_offset)->default_value(.9344e6), "TX LO offset from the RX 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 RX 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_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_rx_freq_range().start() + 50e6;
if (not vm.count("freq_stop")) freq_stop = usrp->get_rx_freq_range().stop() - 50e6;
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
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;
const double bb_imag_freq = -bb_tone_freq;
//capture initial uncorrected value
usrp->set_rx_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_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;
}
}}
//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 = rx_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("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;
}
}
std::cout << std::endl;
//stop the transmitter
threads.interrupt_all();
threads.join_all();
store_results(usrp, results, "RX", "rx", "iq");
return 0;
}
/***********************************************************************
* 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);
}
/***********************************************************************
* Main
**********************************************************************/
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()
("help", "help message")
("verbose", "enable some verbose")
("args", po::value<std::string>(&args)->default_value(""), "device address args [default = \"\"]")
("subdev", po::value<std::string>(&subdev), "Subdevice specification (default: first subdevice, often 'A')")
("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), "Samples per data capture")
("precision", po::value<double>(&precision)->default_value(default_precision), "Correction precision (default=0.0001)")
;
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 a transceiver daughterboard to self-calibrate.\n"
"Note: Not all daughterboards support this feature. Refer to the UHD manual for details.\n"
<< std::endl;
return EXIT_FAILURE;
}
// 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);
//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_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)
{
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;
//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
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;
}
}
}
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 > initial_suppression) //keep result
{
result_t result;
result.freq = tx_lo;
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"))
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();
boost::this_thread::sleep(boost::posix_time::milliseconds(500)); //wait for threads to finish
threads.join_all();
store_results(results, "TX", "tx", "iq", serial);
return EXIT_SUCCESS;
}
/***********************************************************************
* 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 DC Offset 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");
//fail if daughterboard has no serial
check_for_empty_serial(usrp, "TX", "tx", args);
//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_dc_freq = actual_tx_freq - actual_rx_freq;
//capture initial uncorrected value
usrp->set_tx_dc_offset(std::complex<double>(0, 0));
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;
}
}}
//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;
}
if (lowest_offset < initial_dc_dbrms){ //most likely valid, 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;
results.push_back(result);
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;
}
}
std::cout << std::endl;
//stop the transmitter
threads.interrupt_all();
threads.join_all();
store_results(usrp, results, "TX", "tx", "dc");
return 0;
}