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Diffstat (limited to 'gr-digital/lib/ofdm_equalizer_base.cc')
| -rw-r--r-- | gr-digital/lib/ofdm_equalizer_base.cc | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/gr-digital/lib/ofdm_equalizer_base.cc b/gr-digital/lib/ofdm_equalizer_base.cc new file mode 100644 index 0000000000..5209b09c29 --- /dev/null +++ b/gr-digital/lib/ofdm_equalizer_base.cc @@ -0,0 +1,121 @@ +/* -*- c++ -*- */ +/* 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. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <digital/ofdm_equalizer_base.h> + +namespace gr { + namespace digital { + + // *** Base class **************************************************** + ofdm_equalizer_base::ofdm_equalizer_base(int fft_len) : + d_fft_len(fft_len), + d_carr_offset(0) + { + } + + + ofdm_equalizer_base::~ofdm_equalizer_base() + { + } + + + // *** Sub-Base class for 1D equalizers using pilot tones ************* + ofdm_equalizer_1d_pilots::ofdm_equalizer_1d_pilots( + int fft_len, + const std::vector<std::vector<int> > &occupied_carriers, + const std::vector<std::vector<int> > &pilot_carriers, + const std::vector<std::vector<gr_complex> > &pilot_symbols, + int symbols_skipped, + bool input_is_shifted) + : ofdm_equalizer_base(fft_len), + d_occupied_carriers(fft_len, false), + d_pilot_carriers(pilot_carriers.size(), std::vector<bool>(fft_len, false)), + d_pilot_symbols(pilot_symbols.size(), std::vector<gr_complex>(fft_len, gr_complex(0, 0))), + d_symbols_skipped(symbols_skipped), + d_pilot_carr_set(symbols_skipped), + d_channel_state(fft_len, gr_complex(1, 0)) + { + int fft_shift_width = 0; + if (input_is_shifted) { + fft_shift_width = fft_len/2; + } + if (!occupied_carriers.size()) { + std::fill(d_occupied_carriers.begin(), d_occupied_carriers.end(), true); + } else { + for (unsigned i = 0; i < occupied_carriers.size(); i++) { + for (unsigned k = 0; k < occupied_carriers[i].size(); k++) { + int carr_index = occupied_carriers[i][k]; + if (occupied_carriers[i][k] < 0) { + carr_index += fft_len; + } + if (carr_index >= fft_len || carr_index < 0) { + throw std::invalid_argument("data carrier index out of bounds."); + } + d_occupied_carriers[(carr_index + fft_shift_width) % fft_len] = true; + } + } + } + if (pilot_carriers.size()) { + for (unsigned i = 0; i < pilot_carriers.size(); i++) { + if (pilot_carriers[i].size() != pilot_symbols[i].size()) { + throw std::invalid_argument("pilot carriers and -symbols do not match."); + } + for (unsigned k = 0; k < pilot_carriers[i].size(); k++) { + int carr_index = pilot_carriers[i][k]; + if (pilot_carriers[i][k] < 0) { + carr_index += fft_len; + } + if (carr_index >= fft_len || carr_index < 0) { + throw std::invalid_argument("pilot carrier index out of bounds."); + } + d_pilot_carriers[i][(carr_index + fft_shift_width) % fft_len] = true; + d_pilot_symbols[i][(carr_index + fft_shift_width) % fft_len] = pilot_symbols[i][k]; + } + } + } + } + + + ofdm_equalizer_1d_pilots::~ofdm_equalizer_1d_pilots() + { + } + + + void + ofdm_equalizer_1d_pilots::reset() + { + std::fill(d_channel_state.begin(), d_channel_state.end(), gr_complex(1, 0)); + d_pilot_carr_set = d_symbols_skipped; + } + + + void ofdm_equalizer_1d_pilots::get_channel_state(std::vector<gr_complex> &taps) + { + taps = d_channel_state; + } + + } /* namespace digital */ +} /* namespace gr */ + |