Added phase tracker and alignment block for QAM

This commit is contained in:
Thomas Kolb 2019-09-25 23:45:18 +02:00
parent 9107ccc7c0
commit 1a4b6ec075
10 changed files with 319 additions and 2 deletions

View file

@ -27,5 +27,6 @@ install(FILES
hamnet70_async_scrambler.block.yml hamnet70_async_scrambler.block.yml
hamnet70_insert_pilot_symbols.block.yml hamnet70_insert_pilot_symbols.block.yml
hamnet70_correct_frequency_from_pilot_syms.block.yml hamnet70_correct_frequency_from_pilot_syms.block.yml
hamnet70_symbol_interleaver.block.yml DESTINATION share/gnuradio/grc/blocks hamnet70_symbol_interleaver.block.yml
hamnet70_qam_phase_tracker.block.yml DESTINATION share/gnuradio/grc/blocks
) )

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@ -0,0 +1,28 @@
id: hamnet70_qam_phase_tracker
label: QAM Phase Tracker
category: '[hamnet70]'
templates:
imports: import hamnet70
make: hamnet70.qam_phase_tracker(${symbols}, ${alpha}, ${start_tag})
parameters:
- id: symbols
label: Constellation Symbols
dtype: complex_vector
- id: alpha
label: Alpha
dtype: float
- id: start_tag
label: Start Tag
dtype: string
inputs:
- domain: stream
dtype: complex
outputs:
- domain: stream
dtype: complex
file_format: 1

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@ -32,5 +32,6 @@ install(FILES
async_scrambler.h async_scrambler.h
insert_pilot_symbols.h insert_pilot_symbols.h
correct_frequency_from_pilot_syms.h correct_frequency_from_pilot_syms.h
symbol_interleaver.h DESTINATION include/hamnet70 symbol_interleaver.h
qam_phase_tracker.h DESTINATION include/hamnet70
) )

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@ -0,0 +1,55 @@
/* -*- c++ -*- */
/*
* Copyright 2019 Thomas Kolb.
*
* This 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.
*
* This software 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 software; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef INCLUDED_HAMNET70_QAM_PHASE_TRACKER_H
#define INCLUDED_HAMNET70_QAM_PHASE_TRACKER_H
#include <hamnet70/api.h>
#include <gnuradio/sync_block.h>
namespace gr {
namespace hamnet70 {
/*!
* \brief <+description of block+>
* \ingroup hamnet70
*
*/
class HAMNET70_API qam_phase_tracker : virtual public gr::sync_block
{
public:
typedef boost::shared_ptr<qam_phase_tracker> sptr;
/*!
* \brief Return a shared_ptr to a new instance of hamnet70::qam_phase_tracker.
*
* To avoid accidental use of raw pointers, hamnet70::qam_phase_tracker's
* constructor is in a private implementation
* class. hamnet70::qam_phase_tracker::make is the public interface for
* creating new instances.
*/
static sptr make(const std::vector<gr_complex> &symbols, float alpha, const std::string &start_tag);
};
} // namespace hamnet70
} // namespace gr
#endif /* INCLUDED_HAMNET70_QAM_PHASE_TRACKER_H */

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@ -34,6 +34,7 @@ list(APPEND hamnet70_sources
insert_pilot_symbols_impl.cc insert_pilot_symbols_impl.cc
correct_frequency_from_pilot_syms_impl.cc correct_frequency_from_pilot_syms_impl.cc
symbol_interleaver_impl.cc symbol_interleaver_impl.cc
qam_phase_tracker_impl.cc
) )
set(hamnet70_sources "${hamnet70_sources}" PARENT_SCOPE) set(hamnet70_sources "${hamnet70_sources}" PARENT_SCOPE)

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@ -0,0 +1,132 @@
/* -*- c++ -*- */
/*
* Copyright 2019 Thomas Kolb.
*
* This 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.
*
* This software 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 software; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gnuradio/io_signature.h>
#include <gnuradio/expj.h>
#include <gnuradio/math.h>
#include "qam_phase_tracker_impl.h"
namespace gr {
namespace hamnet70 {
qam_phase_tracker::sptr
qam_phase_tracker::make(const std::vector<gr_complex> &symbols, float alpha, const std::string &start_tag)
{
return gnuradio::get_initial_sptr
(new qam_phase_tracker_impl(symbols, alpha, start_tag));
}
/*
* The private constructor
*/
qam_phase_tracker_impl::qam_phase_tracker_impl(const std::vector<gr_complex> &symbols, float alpha, const std::string &start_tag)
: gr::sync_block("qam_phase_tracker",
gr::io_signature::make(1, 1, sizeof(gr_complex)),
gr::io_signature::make(1, 1, sizeof(gr_complex))),
d_alpha(alpha),
d_startTag(pmt::intern(start_tag)),
d_avgPhaseOffset(0.0f)
{
// use only symbols in the upper right quadrant
for(auto s : symbols) {
if(s.real() >= 0 && s.imag() >= 0) {
d_refSymbols.push_back(s);
d_refPhase.push_back(gr::fast_atan2f(s));
}
}
}
/*
* Our virtual destructor.
*/
qam_phase_tracker_impl::~qam_phase_tracker_impl()
{
}
int
qam_phase_tracker_impl::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
const gr_complex *in = (const gr_complex *) input_items[0];
gr_complex *out = (gr_complex *) output_items[0];
for(int i = 0; i < noutput_items; i++) {
out[i] = in[i] * gr_expj(-d_avgPhaseOffset);
std::vector<tag_t> tags;
get_tags_in_window(tags, 0, i, i+1, d_startTag);
if(tags.size() > 0) {
// start tag found on this item -> reset average
d_avgPhaseOffset = 0;
}
// update average phase offset from current symbol
gr_complex rotated = out[i];
float re = rotated.real();
float im = rotated.imag();
// normalize to positive quadrant
if(re < 0 && im > 0) {
rotated *= gr_expj(-M_PI/2);
} else if(re < 0 && im < 0) {
rotated *= -1;
} else if(im < 0) { // && re > 0
rotated *= gr_expj(M_PI/2);
} // else already ok
// find closest reference symbol
float min_dist = 1e9;
size_t closest_idx;
for(size_t r = 0; r < d_refSymbols.size(); r++) {
float d = std::norm(d_refSymbols[r] - rotated);
if(d < min_dist) {
closest_idx = r;
min_dist = d;
}
}
float phase = gr::fast_atan2f(rotated);
float delta_phase = phase - d_refPhase[closest_idx];
if(delta_phase > M_PI/4 || delta_phase < -M_PI/4) {
continue;
}
d_avgPhaseOffset += d_alpha * delta_phase;
}
// Tell runtime system how many output items we produced.
return noutput_items;
}
} /* namespace hamnet70 */
} /* namespace gr */

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@ -0,0 +1,54 @@
/* -*- c++ -*- */
/*
* Copyright 2019 Thomas Kolb.
*
* This 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.
*
* This software 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 software; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifndef INCLUDED_HAMNET70_QAM_PHASE_TRACKER_IMPL_H
#define INCLUDED_HAMNET70_QAM_PHASE_TRACKER_IMPL_H
#include <hamnet70/qam_phase_tracker.h>
namespace gr {
namespace hamnet70 {
class qam_phase_tracker_impl : public qam_phase_tracker
{
private:
pmt::pmt_t d_startTag;
float d_alpha;
float d_avgPhaseOffset;
std::vector<gr_complex> d_refSymbols;
std::vector<float> d_refPhase;
public:
qam_phase_tracker_impl(const std::vector<gr_complex> &symbols, float alpha, const std::string &start_tag);
~qam_phase_tracker_impl();
// Where all the action really happens
int work(
int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items
);
};
} // namespace hamnet70
} // namespace gr
#endif /* INCLUDED_HAMNET70_QAM_PHASE_TRACKER_IMPL_H */

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@ -52,3 +52,4 @@ set(GR_TEST_PYTHON_DIRS ${CMAKE_BINARY_DIR}/swig)
#GR_ADD_TEST(qa_insert_pilot_symbols ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_insert_pilot_symbols.py) #GR_ADD_TEST(qa_insert_pilot_symbols ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_insert_pilot_symbols.py)
#GR_ADD_TEST(qa_correct_frequency_from_pilot_syms ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_correct_frequency_from_pilot_syms.py) #GR_ADD_TEST(qa_correct_frequency_from_pilot_syms ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_correct_frequency_from_pilot_syms.py)
#GR_ADD_TEST(qa_symbol_interleaver ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_symbol_interleaver.py) #GR_ADD_TEST(qa_symbol_interleaver ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_symbol_interleaver.py)
GR_ADD_TEST(qa_qam_phase_tracker ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/qa_qam_phase_tracker.py)

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@ -0,0 +1,41 @@
#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# Copyright 2019 Thomas Kolb.
#
# This 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.
#
# This software 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 software; see the file COPYING. If not, write to
# the Free Software Foundation, Inc., 51 Franklin Street,
# Boston, MA 02110-1301, USA.
#
from gnuradio import gr, gr_unittest
from gnuradio import blocks
import hamnet70_swig as hamnet70
class qa_qam_phase_tracker(gr_unittest.TestCase):
def setUp(self):
self.tb = gr.top_block()
def tearDown(self):
self.tb = None
def test_001_t(self):
# set up fg
self.tb.run()
# check data
if __name__ == '__main__':
gr_unittest.run(qa_qam_phase_tracker)

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@ -18,6 +18,7 @@
#include "hamnet70/insert_pilot_symbols.h" #include "hamnet70/insert_pilot_symbols.h"
#include "hamnet70/correct_frequency_from_pilot_syms.h" #include "hamnet70/correct_frequency_from_pilot_syms.h"
#include "hamnet70/symbol_interleaver.h" #include "hamnet70/symbol_interleaver.h"
#include "hamnet70/qam_phase_tracker.h"
%} %}
@ -42,3 +43,5 @@ GR_SWIG_BLOCK_MAGIC2(hamnet70, insert_pilot_symbols);
GR_SWIG_BLOCK_MAGIC2(hamnet70, correct_frequency_from_pilot_syms); GR_SWIG_BLOCK_MAGIC2(hamnet70, correct_frequency_from_pilot_syms);
%include "hamnet70/symbol_interleaver.h" %include "hamnet70/symbol_interleaver.h"
GR_SWIG_BLOCK_MAGIC2(hamnet70, symbol_interleaver); GR_SWIG_BLOCK_MAGIC2(hamnet70, symbol_interleaver);
%include "hamnet70/qam_phase_tracker.h"
GR_SWIG_BLOCK_MAGIC2(hamnet70, qam_phase_tracker);