uhd: created rx IQ imbalance app to parallel tx

8 files changed, 489 insertions, 93 deletions

diff --git a/host/lib/usrp/common/apply_corrections.cpp b/host/lib/usrp/common/apply_corrections.cpp
index 6929696bb..c3ac4256a 100644
--- a/host/lib/usrp/common/apply_corrections.cpp
+++ b/host/lib/usrp/common/apply_corrections.cpp
@@ -30,33 +30,40 @@
 
 namespace fs = boost::filesystem;
 
-struct tx_fe_cal_t{
-    double tx_lo_freq;
+boost::mutex corrections_mutex;
+
+/***********************************************************************
+ * Helper routines
+ **********************************************************************/
+static double linear_interp(double x, double x0, double y0, double x1, double y1){
+    return y0 + (x - x0)*(y1 - y0)/(x1 - x0);
+}
+
+/***********************************************************************
+ * FE apply corrections implementation
+ **********************************************************************/
+struct fe_cal_t{
+    double lo_freq;
     double iq_corr_real;
     double iq_corr_imag;
 };
 
-static bool tx_fe_cal_comp(tx_fe_cal_t a, tx_fe_cal_t b){
-    return (a.tx_lo_freq < b.tx_lo_freq);
+static bool fe_cal_comp(fe_cal_t a, fe_cal_t b){
+    return (a.lo_freq < b.lo_freq);
 }
 
-boost::mutex corrections_mutex;;
-static uhd::dict<std::string, std::vector<tx_fe_cal_t> > cache;
+static uhd::dict<std::string, std::vector<fe_cal_t> > fe_cal_cache;
 
-static double linear_interp(double x, double x0, double y0, double x1, double y1){
-    return y0 + (x - x0)*(y1 - y0)/(x1 - x0);
-}
-
-static std::complex<double> get_tx_fe_iq_correction(
-    const std::string &key, const double tx_lo_freq
+static std::complex<double> get_fe_iq_correction(
+    const std::string &key, const double lo_freq
 ){
-    const std::vector<tx_fe_cal_t> &datas = cache[key];
+    const std::vector<fe_cal_t> &datas = fe_cal_cache[key];
 
     //search for lo freq
     size_t lo_index = 0;
     size_t hi_index = datas.size()-1;
     for (size_t i = 0; i < datas.size(); i++){
-        if (datas[i].tx_lo_freq > tx_lo_freq){
+        if (datas[i].lo_freq > lo_freq){
             hi_index = i;
             break;
         }
@@ -68,34 +75,32 @@ static std::complex<double> get_tx_fe_iq_correction(
 
     //interpolation time
     return std::complex<double>(
-        linear_interp(tx_lo_freq, datas[lo_index].tx_lo_freq, datas[lo_index].iq_corr_real, datas[hi_index].tx_lo_freq, datas[hi_index].iq_corr_real),
-        linear_interp(tx_lo_freq, datas[lo_index].tx_lo_freq, datas[lo_index].iq_corr_imag, datas[hi_index].tx_lo_freq, datas[hi_index].iq_corr_imag)
+        linear_interp(lo_freq, datas[lo_index].lo_freq, datas[lo_index].iq_corr_real, datas[hi_index].lo_freq, datas[hi_index].iq_corr_real),
+        linear_interp(lo_freq, datas[lo_index].lo_freq, datas[lo_index].iq_corr_imag, datas[hi_index].lo_freq, datas[hi_index].iq_corr_imag)
     );
 }
 
-static void _apply_tx_fe_corrections(
-    uhd::property_tree::sptr sub_tree, //starts at mboards/x
-    const std::string &slot, //name of dboard slot
-    const double tx_lo_freq //actual lo freq
+static void apply_fe_corrections(
+    uhd::property_tree::sptr sub_tree,
+    const uhd::fs_path &db_path,
+    const uhd::fs_path &fe_path,
+    const std::string &file_prefix,
+    const double lo_freq
 ){
-    //path constants
-    const uhd::fs_path tx_db_path = "dboards/" + slot + "/tx_eeprom";
-    const uhd::fs_path tx_fe_path = "tx_frontends/" + slot + "/iq_balance/value";
-
     //extract eeprom serial
-    const uhd::usrp::dboard_eeprom_t db_eeprom = sub_tree->access<uhd::usrp::dboard_eeprom_t>(tx_db_path).get();
+    const uhd::usrp::dboard_eeprom_t db_eeprom = sub_tree->access<uhd::usrp::dboard_eeprom_t>(db_path).get();
 
     //make the calibration file path
-    const fs::path cal_data_path = fs::path(uhd::get_app_path()) / ".uhd" / "cal" / ("tx_fe_cal_v0.1_" + db_eeprom.serial + ".csv");
+    const fs::path cal_data_path = fs::path(uhd::get_app_path()) / ".uhd" / "cal" / (file_prefix + db_eeprom.serial + ".csv");
     if (not fs::exists(cal_data_path)) return;
 
     //parse csv file or get from cache
-    if (not cache.has_key(cal_data_path.string())){
+    if (not fe_cal_cache.has_key(cal_data_path.string())){
         std::ifstream cal_data(cal_data_path.string().c_str());
         const uhd::csv::rows_type rows = uhd::csv::to_rows(cal_data);
 
         bool read_data = false, skip_next = false;;
-        std::vector<tx_fe_cal_t> datas;
+        std::vector<fe_cal_t> datas;
         BOOST_FOREACH(const uhd::csv::row_type &row, rows){
             if (not read_data and not row.empty() and row[0] == "DATA STARTS HERE"){
                 read_data = true;
@@ -107,32 +112,61 @@ static void _apply_tx_fe_corrections(
                 skip_next = false;
                 continue;
             }
-            tx_fe_cal_t data;
-            std::sscanf(row[0].c_str(), "%lf" , &data.tx_lo_freq);
+            fe_cal_t data;
+            std::sscanf(row[0].c_str(), "%lf" , &data.lo_freq);
             std::sscanf(row[1].c_str(), "%lf" , &data.iq_corr_real);
             std::sscanf(row[2].c_str(), "%lf" , &data.iq_corr_imag);
             datas.push_back(data);
         }
-        std::sort(datas.begin(), datas.end(), tx_fe_cal_comp);
-        cache[cal_data_path.string()] = datas;
+        std::sort(datas.begin(), datas.end(), fe_cal_comp);
+        fe_cal_cache[cal_data_path.string()] = datas;
         UHD_MSG(status) << "Loaded " << cal_data_path.string() << std::endl;
 
     }
 
-    sub_tree->access<std::complex<double> >(tx_fe_path)
-        .set(get_tx_fe_iq_correction(cal_data_path.string(), tx_lo_freq));
+    sub_tree->access<std::complex<double> >(fe_path)
+        .set(get_fe_iq_correction(cal_data_path.string(), lo_freq));
 }
 
+/***********************************************************************
+ * Wrapper routines with nice try/catch + print
+ **********************************************************************/
 void uhd::usrp::apply_tx_fe_corrections(
     property_tree::sptr sub_tree, //starts at mboards/x
     const std::string &slot, //name of dboard slot
-    const double tx_lo_freq //actual lo freq
+    const double lo_freq //actual lo freq
 ){
     boost::mutex::scoped_lock l(corrections_mutex);
     try{
-        _apply_tx_fe_corrections(sub_tree, slot, tx_lo_freq);
+        apply_fe_corrections(
+            sub_tree,
+            "dboards/" + slot + "/tx_eeprom",
+            "tx_frontends/" + slot + "/iq_balance/value",
+            "tx_fe_cal_v0.1_",
+            lo_freq
+        );
     }
     catch(const std::exception &e){
         UHD_MSG(error) << "Failure in apply_tx_fe_corrections: " << e.what() << std::endl;
     }
 }
+
+void uhd::usrp::apply_rx_fe_corrections(
+    property_tree::sptr sub_tree, //starts at mboards/x
+    const std::string &slot, //name of dboard slot
+    const double lo_freq //actual lo freq
+){
+    boost::mutex::scoped_lock l(corrections_mutex);
+    try{
+        apply_fe_corrections(
+            sub_tree,
+            "dboards/" + slot + "/rx_eeprom",
+            "rx_frontends/" + slot + "/iq_balance/value",
+            "rx_fe_cal_v0.1_",
+            lo_freq
+        );
+    }
+    catch(const std::exception &e){
+        UHD_MSG(error) << "Failure in apply_rx_fe_corrections: " << e.what() << std::endl;
+    }
+}
diff --git a/host/lib/usrp/common/apply_corrections.hpp b/host/lib/usrp/common/apply_corrections.hpp
index 8aabab636..c516862d1 100644
--- a/host/lib/usrp/common/apply_corrections.hpp
+++ b/host/lib/usrp/common/apply_corrections.hpp
@@ -30,6 +30,12 @@ namespace uhd{ namespace usrp{
         const double tx_lo_freq //actual lo freq
     );
 
+    void apply_rx_fe_corrections(
+        property_tree::sptr sub_tree, //starts at mboards/x
+        const std::string &slot, //name of dboard slot
+        const double rx_lo_freq //actual lo freq
+    );
+
 }} //namespace uhd::usrp
 
 #endif /* INCLUDED_LIBUHD_USRP_COMMON_APPLY_CORRECTIONS_HPP */
diff --git a/host/lib/usrp/usrp2/usrp2_impl.cpp b/host/lib/usrp/usrp2/usrp2_impl.cpp
index 6170948ca..14fa93221 100644
--- a/host/lib/usrp/usrp2/usrp2_impl.cpp
+++ b/host/lib/usrp/usrp2/usrp2_impl.cpp
@@ -608,6 +608,11 @@ usrp2_impl::usrp2_impl(const device_addr_t &_device_addr){
             _tree->access<double>(db_tx_fe_path / name / "freq" / "value")
                 .subscribe(boost::bind(&usrp2_impl::set_tx_fe_corrections, this, mb, _1));
         }
+        const fs_path db_rx_fe_path = mb_path / "dboards" / "A" / "rx_frontends";
+        BOOST_FOREACH(const std::string &name, _tree->list(db_rx_fe_path)){
+            _tree->access<double>(db_rx_fe_path / name / "freq" / "value")
+                .subscribe(boost::bind(&usrp2_impl::set_rx_fe_corrections, this, mb, _1));
+        }
     }
 
     //initialize io handling
@@ -661,8 +666,12 @@ sensor_value_t usrp2_impl::get_ref_locked(const std::string &mb){
     return sensor_value_t("Ref", lock, "locked", "unlocked");
 }
 
-void usrp2_impl::set_tx_fe_corrections(const std::string &mb, const double tx_lo_freq){
-    apply_tx_fe_corrections(this->get_tree()->subtree("/mboards/" + mb), "A", tx_lo_freq);
+void usrp2_impl::set_rx_fe_corrections(const std::string &mb, const double lo_freq){
+    apply_rx_fe_corrections(this->get_tree()->subtree("/mboards/" + mb), "A", lo_freq);
+}
+
+void usrp2_impl::set_tx_fe_corrections(const std::string &mb, const double lo_freq){
+    apply_tx_fe_corrections(this->get_tree()->subtree("/mboards/" + mb), "A", lo_freq);
 }
 
 #include <boost/math/special_functions/round.hpp>
diff --git a/host/lib/usrp/usrp2/usrp2_impl.hpp b/host/lib/usrp/usrp2/usrp2_impl.hpp
index 74ef3d460..278dc713e 100644
--- a/host/lib/usrp/usrp2/usrp2_impl.hpp
+++ b/host/lib/usrp/usrp2/usrp2_impl.hpp
@@ -106,7 +106,8 @@ private:
     uhd::sensor_value_t get_mimo_locked(const std::string &);
     uhd::sensor_value_t get_ref_locked(const std::string &);
 
-    void set_tx_fe_corrections(const std::string &mb, const double tx_lo_freq);
+    void set_rx_fe_corrections(const std::string &mb, const double);
+    void set_tx_fe_corrections(const std::string &mb, const double);
 
     //device properties interface
     uhd::property_tree::sptr get_tree(void) const{
diff --git a/host/utils/CMakeLists.txt b/host/utils/CMakeLists.txt
index 796fdf96f..1185b06cc 100644
--- a/host/utils/CMakeLists.txt
+++ b/host/utils/CMakeLists.txt
@@ -37,7 +37,8 @@ ENDFOREACH(util_source)
 SET(util_share_sources
     usrp_burn_db_eeprom.cpp
     usrp_burn_mb_eeprom.cpp
-    usrp_gen_db_cal_table.cpp
+    usrp_gen_rx_fe_cal_table.cpp
+    usrp_gen_tx_fe_cal_table.cpp
 )
 
 IF(ENABLE_USB)
diff --git a/host/utils/usrp_cal_utils.hpp b/host/utils/usrp_cal_utils.hpp
new file mode 100644
index 000000000..3e2aa6ae0
--- /dev/null
+++ b/host/utils/usrp_cal_utils.hpp
@@ -0,0 +1,85 @@
+//
+// Copyright 2010 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include <vector>
+#include <complex>
+#include <cmath>
+#include <fstream>
+
+struct result_t{double freq, real_corr, imag_corr, sup;};
+
+/***********************************************************************
+ * Constants
+ **********************************************************************/
+static const double tau = 6.28318531;
+static const double alpha = 0.0001; //very tight iir filter
+static const size_t wave_table_len = 8192;
+static const size_t num_search_steps = 5;
+static const size_t num_search_iters = 7;
+static const size_t skip_initial_samps = 20;
+
+/***********************************************************************
+ * Sinusoid wave table
+ **********************************************************************/
+static inline std::vector<std::complex<float> > gen_table(void){
+    std::vector<std::complex<float> > wave_table(wave_table_len);
+    for (size_t i = 0; i < wave_table_len; i++){
+        wave_table[i] = std::polar<float>(1.0, (tau*i)/wave_table_len);
+    }
+    return wave_table;
+}
+
+static inline std::complex<float> wave_table_lookup(const size_t index){
+    static const std::vector<std::complex<float> > wave_table = gen_table();
+    return wave_table[index % wave_table_len];
+}
+
+/***********************************************************************
+ * Compute power of a tone
+ **********************************************************************/
+static inline double compute_tone_dbrms(
+    const std::vector<std::complex<float> > &samples,
+    const double freq //freq is fractional
+){
+    //shift the samples so the tone at freq is down at DC
+    std::vector<std::complex<double> > shifted(samples.size() - skip_initial_samps);
+    for (size_t i = 0; i < shifted.size(); i++){
+        shifted[i] = std::complex<double>(samples[i+skip_initial_samps]) * std::polar<double>(1.0, -freq*tau*i);
+    }
+
+    //filter the samples with a narrow low pass
+    std::complex<double> iir_output = 0, iir_last = 0;
+    double output = 0;
+    for (size_t i = 0; i < shifted.size(); i++){
+        iir_output = alpha * shifted[i] + (1-alpha)*iir_last;
+        iir_last = iir_output;
+        output += std::abs(iir_output);
+    }
+
+    return 20*std::log10(output/shifted.size());
+}
+
+/***********************************************************************
+ * Write a dat file
+ **********************************************************************/
+static inline void write_samples_to_file(
+    const std::vector<std::complex<float> > &samples, const std::string &file
+){
+    std::ofstream outfile(file.c_str(), std::ofstream::binary);
+    outfile.write((const char*)&samples.front(), samples.size()*sizeof(std::complex<float>));
+    outfile.close();
+}
diff --git a/host/utils/usrp_gen_rx_fe_cal_table.cpp b/host/utils/usrp_gen_rx_fe_cal_table.cpp
new file mode 100644
index 000000000..4d5d4168e
--- /dev/null
+++ b/host/utils/usrp_gen_rx_fe_cal_table.cpp
@@ -0,0 +1,310 @@
+//
+// Copyright 2010 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+#include "usrp_cal_utils.hpp"
+#include <uhd/utils/thread_priority.hpp>
+#include <uhd/utils/safe_main.hpp>
+#include <uhd/utils/paths.hpp>
+#include <uhd/utils/algorithm.hpp>
+#include <uhd/property_tree.hpp>
+#include <uhd/usrp/multi_usrp.hpp>
+#include <uhd/usrp/dboard_eeprom.hpp>
+#include <boost/program_options.hpp>
+#include <boost/format.hpp>
+#include <boost/thread/thread.hpp>
+#include <boost/filesystem.hpp>
+#include <boost/math/special_functions/round.hpp>
+#include <iostream>
+#include <fstream>
+#include <complex>
+#include <cmath>
+#include <ctime>
+
+namespace po = boost::program_options;
+namespace fs = boost::filesystem;
+
+/***********************************************************************
+ * Transmit thread
+ **********************************************************************/
+static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_ampl){
+    uhd::set_thread_priority_safe();
+
+    //create a transmit streamer
+    uhd::stream_args_t stream_args("fc32"); //complex floats
+    uhd::tx_streamer::sptr tx_stream = usrp->get_tx_stream(stream_args);
+
+    //setup variables and allocate buffer
+    uhd::tx_metadata_t md;
+    md.has_time_spec = false;
+    std::vector<std::complex<float> > 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++){
+            buff[i] = float(tx_wave_ampl);
+        }
+        tx_stream->send(&buff.front(), buff.size(), md);
+    }
+
+    //send a mini EOB packet
+    md.end_of_burst = true;
+    tx_stream->send("", 0, md);
+}
+
+/***********************************************************************
+ * Tune RX and TX routine
+ **********************************************************************/
+static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double 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);
+    tx_tune_req.dsp_freq_policy = uhd::tune_request_t::POLICY_MANUAL;
+    tx_tune_req.dsp_freq = 0;
+    usrp->set_tx_freq(tx_tune_req);
+
+    //wait for the LOs to become locked
+    boost::this_thread::sleep(boost::posix_time::milliseconds(50));
+    boost::system_time start = boost::get_system_time();
+    while (not usrp->get_tx_sensor("lo_locked").to_bool() or not usrp->get_rx_sensor("lo_locked").to_bool()){
+        if (boost::get_system_time() > start + boost::posix_time::milliseconds(100)){
+            throw std::runtime_error("timed out waiting for TX and/or RX LO to lock");
+        }
+    }
+
+    return usrp->get_rx_freq();
+}
+
+/***********************************************************************
+ * Data capture routine
+ **********************************************************************/
+static void capture_samples(uhd::usrp::multi_usrp::sptr usrp, uhd::rx_streamer::sptr rx_stream, std::vector<std::complex<float> > &buff){
+    uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE);
+    stream_cmd.num_samps = buff.size();
+    stream_cmd.stream_now = true;
+    usrp->issue_stream_cmd(stream_cmd);
+    uhd::rx_metadata_t md;
+    const size_t 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){
+        throw std::runtime_error(str(boost::format(
+            "Unexpected error code 0x%x"
+        ) % md.error_code));
+    }
+    if (num_rx_samps != buff.size()){
+        throw std::runtime_error("did not get all the samples requested");
+    }
+}
+
+/***********************************************************************
+ * Store data to file
+ **********************************************************************/
+static void store_results(uhd::usrp::multi_usrp::sptr usrp, const std::vector<result_t> &results){
+    //extract eeprom serial
+    uhd::property_tree::sptr tree = usrp->get_device()->get_tree();
+    const uhd::fs_path db_path = "/mboards/0/dboards/A/rx_eeprom";
+    const uhd::usrp::dboard_eeprom_t db_eeprom = tree->access<uhd::usrp::dboard_eeprom_t>(db_path).get();
+    if (db_eeprom.serial.empty()) throw std::runtime_error("RX dboard has empty 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 / ("rx_fe_cal_v0.1_" + db_eeprom.serial + ".csv");
+    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());
+    cal_data << boost::format("name, RX Frontend Calibration\n");
+    cal_data << boost::format("serial, %s\n") % db_eeprom.serial;
+    cal_data << boost::format("timestamp, %d\n") % time(NULL);
+    cal_data << boost::format("version, 0, 1\n");
+    cal_data << boost::format("DATA STARTS HERE\n");
+    cal_data << "rx_lo_frequency, rx_iq_correction_real, rx_iq_correction_imag, measured_suppression\n";
+
+    for (size_t i = 0; i < results.size(); i++){
+        cal_data
+            << results[i].freq << ", "
+            << results[i].real_corr << ", "
+            << results[i].imag_corr << ", "
+            << results[i].sup << "\n"
+        ;
+    }
+
+    std::cout << "wrote cal data to " << cal_data_path << std::endl;
+}
+
+/***********************************************************************
+ * Main
+ **********************************************************************/
+int UHD_SAFE_MAIN(int argc, char *argv[]){
+    std::string args;
+    double rate, tx_wave_ampl, tx_offset, freq_step, tx_gain, rx_gain;
+    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 = \"\"]")
+        ("rate", po::value<double>(&rate)->default_value(12.5e6), "RX and TX sample rate in Hz")
+        ("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")
+        ("tx_gain", po::value<double>(&tx_gain)->default_value(0), "TX gain in dB")
+        ("rx_gain", po::value<double>(&rx_gain)->default_value(0), "RX gain in dB")
+        ("freq_step", po::value<double>(&freq_step)->default_value(10e6), "Step size for LO sweep in Hz")
+        ("nsamps", po::value<size_t>(&nsamps)->default_value(10000), "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 Frontend 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 the sample rates
+    usrp->set_rx_rate(rate);
+    usrp->set_tx_rate(rate);
+
+    //set midrange rx gain, default 0 tx gain
+    usrp->set_tx_gain(tx_gain);
+    usrp->set_rx_gain(rx_gain);
+
+    //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<std::complex<float> > buff(nsamps);
+
+    //store the results here
+    std::vector<result_t> results;
+
+    const uhd::meta_range_t freq_range = usrp->get_rx_freq_range();
+    for (double rx_lo_i = freq_range.start()+50e6; rx_lo_i < freq_range.stop()-50e6; rx_lo_i += freq_step){
+        const double rx_lo = tune_rx_and_tx(usrp, rx_lo_i, tx_offset);
+
+        //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 = std::polar(ampl_corr+1, phase_corr*tau);
+                usrp->set_rx_iq_balance(correction);
+
+                //receive some samples
+                capture_samples(usrp, rx_stream, buff);
+
+                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;
+
+                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;
+
+                //std::cout << "bb_tone_freq " << bb_tone_freq << std::endl;
+                //std::cout << "bb_imag_freq " << bb_imag_freq << std::endl;
+                //std::cout << "tone_dbrms " << tone_dbrms << std::endl;
+                //std::cout << "imag_dbrms " << imag_dbrms << std::endl;
+                //std::cout << "suppression " << (tone_dbrms - imag_dbrms) << std::endl;
+
+                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.sup = best_suppression;
+            results.push_back(result);
+        }
+        if (vm.count("verbose")){
+            std::cout << boost::format("%f MHz: best suppression %fdB") % (rx_lo/1e6) % best_suppression << std::endl;
+        }
+        else std::cout << "." << std::flush;
+
+    }
+    std::cout << std::endl;
+
+    //stop the transmitter
+    threads.interrupt_all();
+    threads.join_all();
+
+    store_results(usrp, results);
+
+    return 0;
+}
diff --git a/host/utils/usrp_gen_db_cal_table.cpp b/host/utils/usrp_gen_tx_fe_cal_table.cpp
index 6cee1f18e..1e4a9d11f 100644
--- a/host/utils/usrp_gen_db_cal_table.cpp
+++ b/host/utils/usrp_gen_tx_fe_cal_table.cpp
@@ -15,6 +15,7 @@
 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
 
+#include "usrp_cal_utils.hpp"
 #include <uhd/utils/thread_priority.hpp>
 #include <uhd/utils/safe_main.hpp>
 #include <uhd/utils/paths.hpp>
@@ -30,63 +31,12 @@
 #include <iostream>
 #include <fstream>
 #include <complex>
-#include <cmath>
 #include <ctime>
 
 namespace po = boost::program_options;
 namespace fs = boost::filesystem;
 
 /***********************************************************************
- * Constants
- **********************************************************************/
-static const double tau = 6.28318531;
-static const double alpha = 0.0001; //very tight iir filter
-static const size_t wave_table_len = 8192;
-static const size_t num_search_steps = 5;
-static const size_t num_search_iters = 7;
-
-/***********************************************************************
- * Sinusoid wave table
- **********************************************************************/
-static std::vector<std::complex<float> > gen_table(void){
-    std::vector<std::complex<float> > wave_table(wave_table_len);
-    for (size_t i = 0; i < wave_table_len; i++){
-        wave_table[i] = std::polar<float>(1.0, (tau*i)/wave_table_len);
-    }
-    return wave_table;
-}
-
-static std::complex<float> wave_table_lookup(const size_t index){
-    static const std::vector<std::complex<float> > wave_table = gen_table();
-    return wave_table[index % wave_table_len];
-}
-
-/***********************************************************************
- * Compute power of a tone
- **********************************************************************/
-static double compute_tone_dbrms(
-    const std::vector<std::complex<float> > &samples,
-    const double freq //freq is fractional
-){
-    //shift the samples so the tone at freq is down at DC
-    std::vector<std::complex<double> > shifted(samples.size());
-    for (size_t i = 0; i < shifted.size(); i++){
-        shifted[i] = std::complex<double>(samples[i]) * std::polar<double>(1.0, -freq*tau*i);
-    }
-
-    //filter the samples with a narrow low pass
-    std::complex<double> iir_output = 0, iir_last = 0;
-    double output = 0;
-    for (size_t i = 0; i < shifted.size(); i++){
-        iir_output = alpha * shifted[i] + (1-alpha)*iir_last;
-        iir_last = iir_output;
-        output += std::abs(iir_output);
-    }
-
-    return 20*std::log10(output/shifted.size());
-}
-
-/***********************************************************************
  * Transmit thread
  **********************************************************************/
 static void tx_thread(uhd::usrp::multi_usrp::sptr usrp, const double tx_wave_freq, const double tx_wave_ampl){
@@ -133,6 +83,7 @@ static double tune_rx_and_tx(uhd::usrp::multi_usrp::sptr usrp, const double tx_l
     usrp->set_rx_freq(usrp->get_tx_freq() - rx_offset);
 
     //wait for the LOs to become locked
+    boost::this_thread::sleep(boost::posix_time::milliseconds(50));
     boost::system_time start = boost::get_system_time();
     while (not usrp->get_tx_sensor("lo_locked").to_bool() or not usrp->get_rx_sensor("lo_locked").to_bool()){
         if (boost::get_system_time() > start + boost::posix_time::milliseconds(100)){
@@ -168,7 +119,6 @@ static void capture_samples(uhd::usrp::multi_usrp::sptr usrp, uhd::rx_streamer::
 /***********************************************************************
  * Store data to file
  **********************************************************************/
-struct result_t{double freq, real_corr, imag_corr, sup;};
 static void store_results(uhd::usrp::multi_usrp::sptr usrp, const std::vector<result_t> &results){
     //extract eeprom serial
     uhd::property_tree::sptr tree = usrp->get_device()->get_tree();
@@ -236,7 +186,7 @@ int UHD_SAFE_MAIN(int argc, char *argv[]){
 
     //print the help message
     if (vm.count("help")){
-        std::cout << boost::format("USRP Generate Daughterboard Calibration Table %s") % desc << std::endl;
+        std::cout << boost::format("USRP Generate TX Frontend 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;