gr-digitalhf/lib/adaptive_dfe_impl.h

146 lines
4.1 KiB
C++

/* -*- c++ -*- */
/*
* Copyright 2018 hcab14@mail.com.
*
* 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_DIGITALHF_ADAPTIVE_DFE_IMPL_H
#define INCLUDED_DIGITALHF_ADAPTIVE_DFE_IMPL_H
#include <gnuradio/blocks/control_loop.h>
#include <gnuradio/blocks/rotator.h>
#include <gnuradio/digital/constellation.h>
#include <digitalhf/adaptive_dfe.h>
#include "filter_update.hpp"
#include "volk_alloc.h"
namespace gr {
namespace digitalhf {
class constellation_distance_filter {
public:
constellation_distance_filter(int max_time_constant=10)
: _max_time_constant(max_time_constant)
, _counter(0)
, _pwr(0) {}
void reset(int max_time_constant) {
_max_time_constant = max_time_constant;
_counter = 0;
_pwr = 0;
}
float filter(float x) {
_counter += (_counter < _max_time_constant);
float const alpha = 1.0f/_counter;
_pwr = (1-alpha)*_pwr + alpha*x;
return _pwr;
}
protected:
private:
int _max_time_constant;
int _counter;
float _pwr; // filtered distance to constellation point
} ;
class adaptive_dfe_impl : public adaptive_dfe {
private:
typedef volk::vector<gr_complex> gr_complex_vec_type;
int _sps;
int _nB, _nF, _nW;
int _nGuard;
float _mu;
float _alpha;
bool _use_symbol_taps;
gr_complex_vec_type _tmp;
gr_complex_vec_type _taps_samples;
gr_complex_vec_type _taps_symbols;
gr_complex_vec_type _last_taps_samples;
gr_complex_vec_type _hist_symbols;
int _hist_symbol_index;
std::vector<gr::digital::constellation_sptr> _constellations;
std::vector<constellation_distance_filter> _npwr;
int _npwr_max_time_constant;
int _constellation_index;
std::vector<gr_complex> _symbols;
std::vector<gr_complex> _scramble; // PSK-8 scramble symbols
std::vector<std::array<int,8> > _scramble_xor; // signs for XOR scrambling
std::vector<gr_complex> _descrambled_symbols;
int _symbol_counter;
bool _save_soft_decisions;
std::vector<float> _vec_soft_decisions;
std::map<std::string, pmt::pmt_t> _msg_ports;
pmt::pmt_t _msg_metadata;
int _num_samples_since_filter_update;
gr_complex_vec_type _rotated_samples;
blocks::rotator _rotator;
gr::blocks::control_loop _control_loop;
enum state {
WAIT_FOR_PREAMBLE,
WAIT_FOR_FRAME_INFO,
DO_FILTER
} _state;
filter_update::sptr _filter_update;
void update_constellations(pmt::pmt_t );
void update_frame_info(pmt::pmt_t );
gr_complex filter(gr_complex const* start, gr_complex const* end);
int recenter_filter_taps();
void reset_filter();
void publish_frame_info();
void publish_soft_dec();
public:
adaptive_dfe_impl(int sps, // samples per symbol
int nB, // number of forward FIR taps
int nF, // number of backward FIR taps
int nW, // number of symbol taps
float mu,
float alpha);
virtual ~adaptive_dfe_impl();
void forecast (int noutput_items, gr_vector_int &ninput_items_required);
virtual bool start();
virtual bool stop();
virtual int general_work(int noutput_items,
gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items);
virtual void set_mu(float mu) { _mu = mu; _filter_update->set_parameters({{"mu", mu}}); }
virtual void set_alpha(float alpha) { _alpha = alpha; }
} ;
} // namespace digitalhf
} // namespace gr
#endif /* INCLUDED_DIGITALHF_ADAPTIVE_DFE_IMPL_H */