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/* -*- c++ -*- */
/*
* Copyright 2015 Free Software Foundation, Inc.
*
* SPDX-License-Identifier: GPL-3.0-or-later
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "dvbt_demod_reference_signals_impl.h"
#include <gnuradio/io_signature.h>
namespace gr {
namespace dtv {
dvbt_demod_reference_signals::sptr
dvbt_demod_reference_signals::make(int itemsize,
int ninput,
int noutput,
dvb_constellation_t constellation,
dvbt_hierarchy_t hierarchy,
dvb_code_rate_t code_rate_HP,
dvb_code_rate_t code_rate_LP,
dvb_guardinterval_t guard_interval,
dvbt_transmission_mode_t transmission_mode,
int include_cell_id,
int cell_id)
{
return gnuradio::make_block_sptr<dvbt_demod_reference_signals_impl>(itemsize,
ninput,
noutput,
constellation,
hierarchy,
code_rate_HP,
code_rate_LP,
guard_interval,
transmission_mode,
include_cell_id,
cell_id);
}
/*
* The private constructor
*/
dvbt_demod_reference_signals_impl::dvbt_demod_reference_signals_impl(
int itemsize,
int ninput,
int noutput,
dvb_constellation_t constellation,
dvbt_hierarchy_t hierarchy,
dvb_code_rate_t code_rate_HP,
dvb_code_rate_t code_rate_LP,
dvb_guardinterval_t guard_interval,
dvbt_transmission_mode_t transmission_mode,
int include_cell_id,
int cell_id)
: block("dvbt_demod_reference_signals",
io_signature::make(1, 1, itemsize * ninput),
io_signature::make(1, 1, itemsize * noutput)),
config(constellation,
hierarchy,
code_rate_HP,
code_rate_LP,
guard_interval,
transmission_mode,
include_cell_id,
cell_id),
d_pg(config),
d_init(0),
d_fi_start(0)
{
d_ninput = ninput;
d_noutput = noutput;
// TODO - investigate why this is happening
if ((config.d_constellation == MOD_64QAM) && (config.d_transmission_mode == T8k))
d_fi_start = 2;
else
d_fi_start = 3;
}
/*
* Our virtual destructor.
*/
dvbt_demod_reference_signals_impl::~dvbt_demod_reference_signals_impl() {}
void dvbt_demod_reference_signals_impl::forecast(int noutput_items,
gr_vector_int& ninput_items_required)
{
int ninputs = ninput_items_required.size();
for (int i = 0; i < ninputs; i++)
ninput_items_required[i] = 2 * noutput_items;
}
int dvbt_demod_reference_signals_impl::is_sync_start(int nitems)
{
std::vector<tag_t> tags;
const uint64_t nread = this->nitems_read(0); // number of items read on port 0
this->get_tags_in_range(
tags, 0, nread, nread + nitems, pmt::string_to_symbol("sync_start"));
return !tags.empty() ? 1 : 0;
}
int dvbt_demod_reference_signals_impl::general_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];
int symbol_index = 0;
int frame_index = 0;
int to_out = 0;
for (int i = 0; i < noutput_items; i++) {
to_out += d_pg.parse_input(
&in[i * d_ninput], &out[i * d_noutput], &symbol_index, &frame_index);
}
/*
* Wait for a sync_start tag from upstream that signals when to start.
* Always consume until to a superframe start.
*/
if (is_sync_start(noutput_items)) {
d_init = 0;
}
if (d_init == 0) {
// This is super-frame start
if (((symbol_index % 68) == 0) && ((frame_index % 4) == d_fi_start)) {
d_init = 1;
const uint64_t offset = this->nitems_written(0);
pmt::pmt_t key = pmt::string_to_symbol("superframe_start");
pmt::pmt_t value = pmt::from_long(0xaa);
this->add_item_tag(0, offset, key, value);
} else {
consume_each(1);
return (0);
}
}
// Send a tag for each OFDM symbol informing about
// symbol index.
const uint64_t offset = this->nitems_written(0);
pmt::pmt_t key = pmt::string_to_symbol("symbol_index");
pmt::pmt_t value = pmt::from_long(symbol_index);
this->add_item_tag(0, offset, key, value);
// Consume from input stream
consume_each(noutput_items);
// Tell runtime system how many output items we produced.
return to_out;
}
} /* namespace dtv */
} /* namespace gr */
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