diff options
Diffstat (limited to 'gr-digital/lib/ofdm_serializer_vcc_impl.cc')
| -rw-r--r-- | gr-digital/lib/ofdm_serializer_vcc_impl.cc | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/gr-digital/lib/ofdm_serializer_vcc_impl.cc b/gr-digital/lib/ofdm_serializer_vcc_impl.cc new file mode 100644 index 0000000000..2fdb9bd0e8 --- /dev/null +++ b/gr-digital/lib/ofdm_serializer_vcc_impl.cc @@ -0,0 +1,205 @@ +/* -*- 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 <gr_io_signature.h> +#include "ofdm_serializer_vcc_impl.h" + +namespace gr { + namespace digital { + + ofdm_serializer_vcc::sptr + ofdm_serializer_vcc::make( + int fft_len, + const std::vector<std::vector<int> > &occupied_carriers, + const std::string &len_tag_key, + const std::string &packet_len_tag_key, + int symbols_skipped, + bool input_is_shifted + ) + { + return gnuradio::get_initial_sptr ( + new ofdm_serializer_vcc_impl( + fft_len, occupied_carriers, + len_tag_key, packet_len_tag_key, + symbols_skipped, input_is_shifted + ) + ); + } + + ofdm_serializer_vcc::sptr + ofdm_serializer_vcc::make( + const digital_ofdm_carrier_allocator_cvc_sptr &allocator, + const std::string &packet_len_tag_key, + int symbols_skipped, + bool input_is_shifted + ) + { + return gnuradio::get_initial_sptr( + new ofdm_serializer_vcc_impl( + allocator->fft_len(), + allocator->occupied_carriers(), + allocator->len_tag_key(), + packet_len_tag_key, + symbols_skipped, + input_is_shifted + ) + ); + } + + ofdm_serializer_vcc_impl::ofdm_serializer_vcc_impl ( + int fft_len, + const std::vector<std::vector<int> > &occupied_carriers, + const std::string &len_tag_key, + const std::string &packet_len_tag_key, + int symbols_skipped, + bool input_is_shifted) + : gr_tagged_stream_block ("ofdm_serializer_vcc", + gr_make_io_signature(1, 1, sizeof (gr_complex) * fft_len), + gr_make_io_signature(1, 1, sizeof (gr_complex)), + len_tag_key), + d_fft_len(fft_len), + d_occupied_carriers(occupied_carriers), + d_packet_len_tag_key(pmt::pmt_string_to_symbol(packet_len_tag_key)), + d_out_len_tag_key(pmt::pmt_string_to_symbol((packet_len_tag_key.empty() ? len_tag_key : packet_len_tag_key))), + d_symbols_skipped(symbols_skipped % occupied_carriers.size()), + d_curr_set(symbols_skipped % occupied_carriers.size()), + d_symbols_per_set(0) + { + for (unsigned i = 0; i < d_occupied_carriers.size(); i++) { + for (unsigned k = 0; k < d_occupied_carriers[i].size(); k++) { + if (d_occupied_carriers[i][k] < 0) { + d_occupied_carriers[i][k] += fft_len; + } + if (d_occupied_carriers[i][k] >= fft_len || d_occupied_carriers[i][k] < 0) { + throw std::invalid_argument("ofdm_serializer_vcc: trying to occupy a carrier outside the fft length."); + } + if (input_is_shifted) { + d_occupied_carriers[i][k] = (d_occupied_carriers[i][k] + fft_len) % fft_len; + } + } + } + + for (unsigned i = 0; i < d_occupied_carriers.size(); i++) { + d_symbols_per_set += d_occupied_carriers[i].size(); + } + set_relative_rate((double) d_symbols_per_set / d_occupied_carriers.size()); + set_tag_propagation_policy(TPP_DONT); + } + + ofdm_serializer_vcc_impl::~ofdm_serializer_vcc_impl() + { + } + + int + ofdm_serializer_vcc_impl::calculate_output_stream_length(const gr_vector_int &ninput_items) + { + int nout = (ninput_items[0] / d_occupied_carriers.size()) * d_symbols_per_set; + for (unsigned i = 0; i < ninput_items[0] % d_occupied_carriers.size(); i++) { + nout += d_occupied_carriers[(i + d_curr_set) % d_occupied_carriers.size()].size(); + } + return nout; + } + + void + ofdm_serializer_vcc_impl::update_length_tags(int n_produced, int n_ports) + { + add_item_tag(0, nitems_written(0), + d_out_len_tag_key, + pmt::pmt_from_long(n_produced) + ); + } + + int + ofdm_serializer_vcc_impl::work (int noutput_items, + gr_vector_int &ninput_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]; + long frame_length = ninput_items[0]; // Input frame + long packet_length = 0; // Output frame + int carr_offset = 0; + + std::vector<gr_tag_t> tags; + // Packet mode + if (!d_length_tag_key_str.empty()) { + get_tags_in_range(tags, 0, nitems_read(0), nitems_read(0)+1); + for (unsigned i = 0; i < tags.size(); i++) { + if (pmt::pmt_symbol_to_string(tags[i].key) == "ofdm_sync_carr_offset") { + carr_offset = pmt::pmt_to_long(tags[i].value); + } + if (tags[i].key == d_packet_len_tag_key) { + packet_length = pmt::pmt_to_long(tags[i].value); + remove_item_tag(0, tags[i]); + } + } + } else { + // recalc frame length from noutput_items + frame_length = 0; + int sym_per_frame = 0; + while ((sym_per_frame + d_occupied_carriers[(frame_length + 1) % d_occupied_carriers.size()].size()) < noutput_items) { + frame_length++; + sym_per_frame += d_occupied_carriers[(frame_length + 1) % d_occupied_carriers.size()].size(); + } + } + + // Copy symbols + int n_out_symbols = 0; + for (int i = 0; i < frame_length; i++) { + // Copy all tags associated with this input OFDM symbol onto the first output symbol + get_tags_in_range(tags, 0, + nitems_read(0)+i, + nitems_read(0)+i+1 + ); + for (unsigned t = 0; t < tags.size(); t++) { + add_item_tag(0, nitems_written(0)+n_out_symbols, + tags[i].key, + tags[i].value + ); + } + for (unsigned k = 0; k < d_occupied_carriers[d_curr_set].size(); k++) { + out[n_out_symbols++] = in[i * d_fft_len + d_occupied_carriers[d_curr_set][k] + carr_offset]; + } + if (packet_length && n_out_symbols > packet_length) { + n_out_symbols = packet_length; + break; + } + d_curr_set = (d_curr_set + 1) % d_occupied_carriers.size(); + } + + // Housekeeping + if (d_length_tag_key_str.empty()) { + consume_each(frame_length); + } else { + d_curr_set = d_symbols_skipped; + } + + return n_out_symbols; + } + + } /* namespace digital */ +} /* namespace gr */ + |