bladerf: implement DC offset and IQ imbalance correction

This patch has been provided by Brent J.
wip-signat
Dimitri Stolnikov 9 years ago
parent 80c4af4f31
commit e68f8505df
  1. 9
      lib/bladerf/bladerf_common.h
  2. 52
      lib/bladerf/bladerf_sink_c.cc
  3. 3
      lib/bladerf/bladerf_sink_c.h
  4. 48
      lib/bladerf/bladerf_source_c.cc

@ -43,6 +43,15 @@
/* We currently read/write 1024 samples (pairs of 16-bit signed ints) */
#define BLADERF_SAMPLE_BLOCK_SIZE (1024)
/*
* BladeRF IQ correction defines
*/
#define BLADERF_RX_DC_RANGE 63
#define BLADERF_TX_DC_RANGE 127
#define BLADERF_GAIN_ZERO 4096
#define BLADERF_GAIN_RANGE 4096
#define BLADERF_PHASE_RANGE 2048
typedef boost::shared_ptr<struct bladerf> bladerf_sptr;
class bladerf_common

@ -520,6 +520,50 @@ std::string bladerf_sink_c::get_antenna( size_t chan )
return "TX";
}
void bladerf_sink_c::set_dc_offset( const std::complex<double> &offset, size_t chan )
{
int ret = 0;
int16_t val_i,val_q;
//the lms dc correction provides for 6 bits of DC correction and 1 sign bit
//scale the correction appropriately
val_i = (int16_t)(fabs(offset.real()) * BLADERF_TX_DC_RANGE);
val_q = (int16_t)(fabs(offset.imag()) * BLADERF_TX_DC_RANGE);
val_i = (offset.real() > 0) ? val_i : -val_i;
val_q = (offset.imag() > 0) ? val_q : -val_q;
ret = bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_TX_DC_I, val_i);
ret |= bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_TX_DC_Q, val_q);
if( ret ) {
throw std::runtime_error( std::string(__FUNCTION__) + " " +
"could not set dc offset: " +
std::string(bladerf_strerror(ret)) );
}
}
void bladerf_sink_c::set_iq_balance( const std::complex<double> &balance, size_t chan )
{
int ret = 0;
int16_t val_gain,val_phase;
//FPGA gain correction defines 0.0 as BLADERF_GAIN_ZERO, scale the offset range to +/- BLADERF_GAIN_RANGE
val_gain = (int16_t)(balance.real() * (int16_t)BLADERF_GAIN_RANGE) + BLADERF_GAIN_ZERO;
//FPGA phase correction steps from -45 to 45 degrees
val_phase = (int16_t)(balance.imag() * BLADERF_PHASE_RANGE);
ret = bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_TX_GAIN, val_gain);
ret |= bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_TX_PHASE, val_phase);
if( ret ) {
throw std::runtime_error( std::string(__FUNCTION__) + " " +
"could not set iq balance: " +
std::string(bladerf_strerror(ret)) );
}
}
double bladerf_sink_c::set_bandwidth( double bandwidth, size_t chan )
{
int ret;
@ -531,8 +575,8 @@ double bladerf_sink_c::set_bandwidth( double bandwidth, size_t chan )
ret = bladerf_set_bandwidth( _dev.get(), BLADERF_MODULE_TX, (uint32_t)bandwidth, &actual );
if( ret ) {
throw std::runtime_error( std::string(__FUNCTION__) + " " +
"Could not set bandwidth, error " +
boost::lexical_cast<std::string>(ret) );
"could not set bandwidth:" +
std::string(bladerf_strerror(ret)) );
}
return get_bandwidth();
@ -546,8 +590,8 @@ double bladerf_sink_c::get_bandwidth( size_t chan )
ret = bladerf_get_bandwidth( _dev.get(), BLADERF_MODULE_TX, &bandwidth );
if( ret ) {
throw std::runtime_error( std::string(__FUNCTION__) + " " +
"Could not get bandwidth, error " +
boost::lexical_cast<std::string>(ret) );
"could not get bandwidth: " +
std::string(bladerf_strerror(ret)) );
}
return (double)bandwidth;

@ -102,6 +102,9 @@ public:
std::string set_antenna( const std::string & antenna, size_t chan = 0 );
std::string get_antenna( size_t chan = 0 );
void set_dc_offset( const std::complex<double> &offset, size_t chan );
void set_iq_balance( const std::complex<double> &balance, size_t chan );
double set_bandwidth( double bandwidth, size_t chan = 0 );
double get_bandwidth( size_t chan = 0 );
osmosdr::freq_range_t get_bandwidth_range( size_t chan = 0 );

@ -47,7 +47,6 @@
#define BLADERF_SAMPLE_FIFO_MIN_SIZE (3 * BLADERF_SAMPLE_BLOCK_SIZE)
using namespace boost::assign;
/*
@ -561,40 +560,71 @@ std::string bladerf_source_c::get_antenna( size_t chan )
void bladerf_source_c::set_dc_offset_mode( int mode, size_t chan )
{
std::cerr << __FUNCTION__ << " mode: " << mode << std::endl; /* TODO: remove */
if ( osmosdr::source::DCOffsetOff == mode ) {
//_src->set_auto_dc_offset( false, chan );
//_src->set_dc_offset( std::complex<double>(0.0, 0.0), chan ); /* TODO: reset to default for off-state */
set_dc_offset( std::complex<double>(0.0, 0.0), chan ); /* reset to default for off-state */
} else if ( osmosdr::source::DCOffsetManual == mode ) {
//_src->set_auto_dc_offset( false, chan ); /* disable auto mode, but keep correcting with last known values */
} else if ( osmosdr::source::DCOffsetAutomatic == mode ) {
//_src->set_auto_dc_offset( true, chan );
std::cerr << "Automatic DC correction mode is not implemented." << std::endl;
}
}
void bladerf_source_c::set_dc_offset( const std::complex<double> &offset, size_t chan )
{
std::cerr << __FUNCTION__ << " offset: " << offset.real() << " " << offset.imag() << std::endl; /* TODO: remove */
int ret = 0;
int16_t val_i,val_q;
//the lms dc correction provides for 6 bits of DC correction and 1 sign bit
//scale the correction appropriately
val_i = (int16_t)(fabs(offset.real()) * BLADERF_RX_DC_RANGE);
val_q = (int16_t)(fabs(offset.imag()) * BLADERF_RX_DC_RANGE);
val_i = (offset.real() > 0) ? val_i : -val_i;
val_q = (offset.imag() > 0) ? val_q : -val_q;
ret = bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_RX_DC_I, val_i);
ret |= bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_RX_DC_Q, val_q);
if( ret ) {
throw std::runtime_error( std::string(__FUNCTION__) + " " +
"could not set dc offset: " +
std::string(bladerf_strerror(ret)) );
}
}
void bladerf_source_c::set_iq_balance_mode( int mode, size_t chan )
{
std::cerr << __FUNCTION__ << " mode: " << mode << std::endl; /* TODO: remove */
if ( osmosdr::source::IQBalanceOff == mode ) {
//_src->set_auto_iq_balance( false, chan );
//_src->set_iq_balance( std::complex<double>(0.0, 0.0), chan ); /* TODO: reset to default for off-state */
set_iq_balance( std::complex<double>(0.0, 0.0), chan ); /* reset to default for off-state */
} else if ( osmosdr::source::IQBalanceManual == mode ) {
//_src->set_auto_iq_balance( false, chan ); /* disable auto mode, but keep correcting with last known values */
} else if ( osmosdr::source::IQBalanceAutomatic == mode ) {
//_src->set_auto_iq_balance( true, chan );
std::cerr << "Automatic IQ correction mode is not implemented." << std::endl;
}
}
void bladerf_source_c::set_iq_balance( const std::complex<double> &balance, size_t chan )
{
std::cerr << __FUNCTION__ << " balance: " << balance.real() << " " << balance.imag() << std::endl; /* TODO: remove */
int ret = 0;
int16_t val_gain,val_phase;
//FPGA gain correction defines 0.0 as BLADERF_GAIN_ZERO, scale the offset range to +/- BLADERF_GAIN_RANGE
val_gain = (int16_t)(balance.real() * (int16_t)BLADERF_GAIN_RANGE) + BLADERF_GAIN_ZERO;
//FPGA phase correction steps from -45 to 45 degrees
val_phase = (int16_t)(balance.imag() * BLADERF_PHASE_RANGE);
ret = bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_RX_GAIN, val_gain);
ret |= bladerf_set_correction(_dev.get(), BLADERF_IQ_CORR_RX_PHASE, val_phase);
if( ret ) {
throw std::runtime_error( std::string(__FUNCTION__) + " " +
"could not set iq balance: " +
std::string(bladerf_strerror(ret)) );
}
}
double bladerf_source_c::set_bandwidth( double bandwidth, size_t chan )

Loading…
Cancel
Save