gr-satnogs/lib/frame_acquisition_impl.h

109 lines
3.2 KiB
C++

/* -*- c++ -*- */
/*
* gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
*
* Copyright (C) 2018, Libre Space Foundation <http://librespacefoundation.org/>
*
* This program 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 of the License, or
* (at your option) any later version.
*
* This program 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 program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef INCLUDED_SATNOGS_FRAME_ACQUISITION_IMPL_H
#define INCLUDED_SATNOGS_FRAME_ACQUISITION_IMPL_H
#include <satnogs/shift_reg.h>
#include <satnogs/frame_acquisition.h>
namespace gr {
namespace satnogs {
class frame_acquisition_impl : public frame_acquisition {
public:
frame_acquisition_impl(variant_t variant,
const std::vector<uint8_t> &preamble,
size_t preamble_threshold,
const std::vector<uint8_t> &sync,
size_t sync_threshold,
size_t frame_size_field_len,
size_t frame_len,
checksum_t crc,
whitening::whitening_sptr descrambler,
size_t max_frame_len);
~frame_acquisition_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);
private:
/**
* Decoding FSM
*/
typedef enum {
SEARCHING, //!< when searching for the start of the preamble
SEARCHING_SYNC,
DECODING_GENERIC_FRAME_LEN,
DECODING_GOLAY24_FRAME_LEN,
DECODING_PAYLOAD
} decoding_state_t;
const variant_t d_variant;
shift_reg d_preamble;
shift_reg d_preamble_shift_reg;
const size_t d_preamble_len;
const size_t d_preamble_thrsh;
shift_reg d_sync;
shift_reg d_sync_shift_reg;
const size_t d_sync_len;
const size_t d_sync_thrsh;
decoding_state_t d_state;
uint32_t d_cnt;
uint32_t d_frame_size_field_len;
uint32_t d_frame_len;
const uint32_t d_max_frame_len;
const checksum_t d_crc;
uint32_t d_crc_len;
whitening::whitening_sptr d_whitening;
uint8_t *d_pdu;
int
searching_preamble(const uint8_t *in, int len);
int
searching_sync(const uint8_t *in, int len);
int dec_generic_frame_len(const uint8_t *in, int len);
int dec_golay24_frame_len(const uint8_t *in, int len);
int
decoding(const uint8_t *in, int len);
void
reset();
bool
check_crc();
};
} // namespace satnogs
} // namespace gr
#endif /* INCLUDED_SATNOGS_FRAME_ACQUISITION_IMPL_H */