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jynik/bladerf_dc_iq_corr.py

Last active April 16, 2023 23:18
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bladeRF: manual DC Offset and IQ Imbalance correction
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bladerf_dc_iq_corr.py
#!/usr/bin/python2
#!/usr/bin/env python2
#
# This script puts the bladeRF into an RF loopback mode, transmitting
# a vector at an offset from the RX frequency. The resulting image may be used
# to manually dial in RX-side IQ imbalance correction. Sliders to minimize the RX
# DC offset are also included.
#
# License: GPLv3
#
# This script was derived from the gr-osmosdr's osmocom_fft script.
# http://sdr.osmocom.org/trac/wiki/GrOsmoSDR
#
# The copyright information from osmocom_fft is provided below.
# -----------------------------------------------------------------------------
# Copyright 2012 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# GNU Radio 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, or (at your option)
# any later version.
#
# GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
#
DEFAULT_RX_FREQ = 300e6
DEFAULT_SAMPLE_RATE = 24e5
DEFAULT_TX_FREQ_OFFSET = (DEFAULT_SAMPLE_RATE / 4)
DEFAULT_FFT_SIZE = 2048
KEY_RX_FREQ = 'rx_freq'
KEY_TX_FREQ_OFF = 'tx_freq_off'
KEY_SAMPLE_RATE = 'sample_rate'
KEY_DC_OFF_I = 'dc_offset_real'
KEY_DC_OFF_Q = 'dc_offset_imag'
KEY_IQ_BAL_I = 'iq_balance_mag'
KEY_IQ_BAL_Q = 'iq_balance_pha'
import osmosdr
from gnuradio import gr, gru, eng_notation, analog
from gnuradio.gr.pubsub import pubsub
from gnuradio.eng_option import eng_option
from optparse import OptionParser
try:
from gnuradio.wxgui import stdgui2, form, slider, forms, fftsink2, scopesink2
import wx
except ImportError:
sys.stderr.write('Error importing GNU Radio\'s wxgui. Please make sure gr-wxgui is installed.\n')
sys.exit(1)
class top_block(stdgui2.std_top_block, pubsub):
def __init__(self, frame, panel, vbox, argv):
stdgui2.std_top_block.__init__(self, frame, panel, vbox, argv)
pubsub.__init__(self)
self.frame = frame
self.panel = panel
parser = OptionParser(option_class=eng_option)
parser.add_option('-a', '--args', type='string', default='bladerf=0',
help='Device args, [default=%default]')
parser.add_option('-s', '--sample-rate', type='eng_float', default=DEFAULT_SAMPLE_RATE,
help='Sample rate [default=%default]')
parser.add_option('-f', '--rx-freq', type='eng_float', default=DEFAULT_RX_FREQ,
help='RX frequency [default=%default]')
parser.add_option('-o', '--tx-freq-off', type='eng_float', default=DEFAULT_TX_FREQ_OFFSET,
help='TX frequency offset [default=%default]')
parser.add_option("", "--avg-alpha", type="eng_float", default=1e-1,
help="Set fftsink averaging factor, default=[%default]")
parser.add_option("", "--averaging", action="store_true", default=False,
help="Enable fftsink averaging, default=[%default]")
parser.add_option("", "--ref-scale", type="eng_float", default=1.0,
help="Set dBFS=0dB input value, default=[%default]")
parser.add_option("", "--fft-size", type="int", default=DEFAULT_FFT_SIZE,
help="Set number of FFT bins [default=%default]")
parser.add_option("", "--fft-rate", type="int", default=30,
help="Set FFT update rate, [default=%default]")
parser.add_option("-v", "--verbose", action="store_true", default=False,
help="Use verbose console output [default=%default]")
(options, args) = parser.parse_args()
if len(args) != 0:
parser.print_help()
sys.exit(1)
self.options = options
if options.rx_freq >= 1.5e6:
options.args += ',loopback=rf_lna1'
else:
options.args += ',loopback=rf_lna2'
self._verbose = options.verbose
self.src = osmosdr.source(options.args)
self.sink = osmosdr.sink(options.args)
self.src.set_sample_rate(options.sample_rate)
self.sink.set_sample_rate(options.sample_rate)
self.src.set_bandwidth(0.90 * options.sample_rate)
self.sink.set_bandwidth(0.90 * options.sample_rate)
self[KEY_RX_FREQ] = options.rx_freq
self[KEY_TX_FREQ_OFF] = options.tx_freq_off
self[KEY_DC_OFF_I] = 0
self[KEY_DC_OFF_Q] = 0
self[KEY_IQ_BAL_I] = 0
self[KEY_IQ_BAL_Q] = 0
self.subscribe(KEY_RX_FREQ, self.set_freq)
self.subscribe(KEY_DC_OFF_I, self.set_dc_offset)
self.subscribe(KEY_DC_OFF_Q, self.set_dc_offset)
self.subscribe(KEY_IQ_BAL_I, self.set_iq_balance)
self.subscribe(KEY_IQ_BAL_Q, self.set_iq_balance)
self.fft = fftsink2.fft_sink_c(panel,
fft_size=options.fft_size,
sample_rate=options.sample_rate,
ref_scale=options.ref_scale,
ref_level=0,
y_divs=10,
average=options.averaging,
avg_alpha=options.avg_alpha,
fft_rate=options.fft_rate)
self.fft.set_callback(self.wxsink_callback)
self.connect(self.src, self.fft)
self.scope = scopesink2.scope_sink_c(panel,
sample_rate = options.sample_rate,
v_scale = 0,
v_offest = 0,
t_scale = 0,
ac_couple = False,
xy_mode = True,
num_inputs = 1)
self.connect(self.src, self.scope)
self.constant_source = analog.sig_source_c(0, analog.GR_CONST_WAVE, 0, 0, 1)
self.connect(self.constant_source, self.sink)
self.set_freq(options.rx_freq)
self.frame.SetMinSize((800, 420))
self._build_gui(vbox)
def set_dc_offset(self, value):
correction = complex(self[KEY_DC_OFF_I], self[KEY_DC_OFF_Q])
try:
self.src.set_dc_offset(correction)
if self._verbose:
print "Set DC offset to", correction
except RuntimeError as ex:
print ex
def set_iq_balance(self, value):
correction = complex(self[KEY_IQ_BAL_I], self[KEY_IQ_BAL_Q])
try:
self.src.set_iq_balance(correction)
if self._verbose:
print "Set IQ balance to", correction
except RuntimeError as ex:
print ex
def wxsink_callback(self, x, y):
self.set_freq_from_callback(x)
def set_freq_from_callback(self, freq):
freq = self.src.set_center_freq(freq)
self[KEY_RX_FREQ] = freq;
def set_freq(self, freq):
if freq is None:
f = self[FREQ_RANGE_KEY]
freq = float(f.start()+f.stop())/2.0
if self._verbose:
print "Using auto-calculated mid-point frequency"
self[KEY_RX_FREQ] = freq
return
self.sink.set_center_freq(freq + self[KEY_TX_FREQ_OFF])
freq = self.src.set_center_freq(freq)
if hasattr(self.fft, 'set_baseband_freq'):
self.fft.set_baseband_freq(freq)
if freq is not None:
if self._verbose:
print "Set center frequency to", freq
elif self._verbose:
print "Failed to set freq."
return freq
def _build_gui(self, vbox):
vbox.Add(self.fft.win, 1, wx.EXPAND)
vbox.Add(self.scope.win, 1, wx.EXPAND)
vbox.AddSpacer(3)
# add control area at the bottom
self.myform = myform = form.form()
##################################################
# DC Offset controls
##################################################
dc_offset_vbox = forms.static_box_sizer(parent=self.panel,
label="DC Offset Correction",
orient=wx.VERTICAL,
bold=True)
dc_offset_vbox.AddSpacer(3)
# First row of sample rate controls
dc_offset_hbox = wx.BoxSizer(wx.HORIZONTAL)
dc_offset_vbox.Add(dc_offset_hbox, 0, wx.EXPAND)
dc_offset_vbox.AddSpacer(3)
# Add frequency controls to top window sizer
vbox.Add(dc_offset_vbox, 0, wx.EXPAND)
vbox.AddSpacer(3)
dc_offset_hbox.AddSpacer(3)
self.dc_offset_real_text = forms.text_box(
parent=self.panel, sizer=dc_offset_hbox,
label='Real',
proportion=1,
converter=forms.float_converter(),
ps=self,
key='dc_offset_real',
)
dc_offset_hbox.AddSpacer(3)
self.dc_offset_real_slider = forms.slider(
parent=self.panel, sizer=dc_offset_hbox,
proportion=3,
minimum=-1,
maximum=+1,
step_size=0.0005,
ps=self,
key='dc_offset_real',
)
dc_offset_hbox.AddSpacer(3)
dc_offset_hbox.AddSpacer(3)
self.dc_offset_imag_text = forms.text_box(
parent=self.panel, sizer=dc_offset_hbox,
label='Imag',
proportion=1,
converter=forms.float_converter(),
ps=self,
key='dc_offset_imag',
)
dc_offset_hbox.AddSpacer(3)
self.dc_offset_imag_slider = forms.slider(
parent=self.panel, sizer=dc_offset_hbox,
proportion=3,
minimum=-1,
maximum=+1,
step_size=0.0005,
ps=self,
key='dc_offset_imag',
)
dc_offset_hbox.AddSpacer(3)
##################################################
# IQ Imbalance controls
##################################################
iq_balance_vbox = forms.static_box_sizer(parent=self.panel,
label="IQ Imbalance Correction",
orient=wx.VERTICAL,
bold=True)
iq_balance_vbox.AddSpacer(3)
# First row of sample rate controls
iq_balance_hbox = wx.BoxSizer(wx.HORIZONTAL)
iq_balance_vbox.Add(iq_balance_hbox, 0, wx.EXPAND)
iq_balance_vbox.AddSpacer(3)
# Add frequency controls to top window sizer
vbox.Add(iq_balance_vbox, 0, wx.EXPAND)
vbox.AddSpacer(3)
iq_balance_hbox.AddSpacer(3)
self.iq_balance_mag_text = forms.text_box(
parent=self.panel, sizer=iq_balance_hbox,
label='Mag',
proportion=1,
converter=forms.float_converter(),
ps=self,
key=KEY_IQ_BAL_I,
)
iq_balance_hbox.AddSpacer(3)
self.iq_balance_mag_slider = forms.slider(
parent=self.panel, sizer=iq_balance_hbox,
proportion=3,
minimum=-1,
maximum=+1,
step_size=0.00025,
ps=self,
key=KEY_IQ_BAL_I,
)
iq_balance_hbox.AddSpacer(3)
iq_balance_hbox.AddSpacer(3)
self.iq_balance_pha_text = forms.text_box(
parent=self.panel, sizer=iq_balance_hbox,
label='Phase',
proportion=1,
converter=forms.float_converter(),
ps=self,
key=KEY_IQ_BAL_Q,
)
iq_balance_hbox.AddSpacer(3)
self.iq_balance_pha_slider = forms.slider(
parent=self.panel, sizer=iq_balance_hbox,
proportion=3,
minimum=-1,
maximum=+1,
step_size=0.00025,
ps=self,
key=KEY_IQ_BAL_Q,
)
iq_balance_hbox.AddSpacer(3)
def main():
app = stdgui2.stdapp(top_block, 'bladeRF: manual DC Offset and IQ Imbalance correction', nstatus=1)
app.MainLoop()
if __name__ == '__main__':
main ()
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