mayhem-firmware/firmware/common/adsb.hpp

/*
 * Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
 * Copyright (C) 2016 Furrtek
 *
 * This file is part of PortaPack.
 *
 * 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 2, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef __ADSB_H__
#define __ADSB_H__

#include "adsb_frame.hpp"
#include "ui.hpp"

#include <cstring>
#include <string>

namespace adsb {

enum downlink_format {
    DF_ADSB = 17,
    DF_EHS_SQUAWK = 21,  // DF 21: Comm-B with identity reply . Mode S enhanced surveillance of squawk + (MB_field = Track and turn report (BDS 5,0)).
                         // Confirmed that it is Detected correctly by dump1090. and sdrangel.
};

enum type_code {
    TC_IDENT = 4,
    TC_AIRBORNE_POS = 11,
    TC_AIRBORNE_VELO = 19
};

enum data_selector {
    BDS_ID = 0x20,
    BDS_ID_MARKS = 0x21,
    BDS_INTENT = 0x40,
    BDS_HEADING = 0x60
};

struct adsb_pos {
    bool valid;
    float latitude;
    float longitude;
    int32_t altitude;
};

struct adsb_vel {
    bool valid;
    int32_t speed;     // knot
    uint16_t heading;  // degree
    int32_t v_rate;    // ft/min
};

const float CPR_MAX_VALUE = 131072.0;

const float adsb_lat_lut[58] = {
    10.47047130, 14.82817437, 18.18626357, 21.02939493,
    23.54504487, 25.82924707, 27.93898710, 29.91135686,
    31.77209708, 33.53993436, 35.22899598, 36.85025108,
    38.41241892, 39.92256684, 41.38651832, 42.80914012,
    44.19454951, 45.54626723, 46.86733252, 48.16039128,
    49.42776439, 50.67150166, 51.89342469, 53.09516153,
    54.27817472, 55.44378444, 56.59318756, 57.72747354,
    58.84763776, 59.95459277, 61.04917774, 62.13216659,
    63.20427479, 64.26616523, 65.31845310, 66.36171008,
    67.39646774, 68.42322022, 69.44242631, 70.45451075,
    71.45986473, 72.45884545, 73.45177442, 74.43893416,
    75.42056257, 76.39684391, 77.36789461, 78.33374083,
    79.29428225, 80.24923213, 81.19801349, 82.13956981,
    83.07199445, 83.99173563, 84.89166191, 85.75541621,
    86.53536998, 87.00000000};

const float PI = 3.14159265358979323846;

const float NZ = 15.0;

void make_frame_adsb(ADSBFrame& frame, const uint32_t ICAO_address);

void encode_frame_id(ADSBFrame& frame, const uint32_t ICAO_address, const std::string& callsign);
std::string decode_frame_id(ADSBFrame& frame);

void encode_frame_pos(ADSBFrame& frame, const uint32_t ICAO_address, const int32_t altitude, const float latitude, const float longitude, const uint32_t time_parity);

adsb_pos decode_frame_pos(ADSBFrame& frame_even, ADSBFrame& frame_odd);

void encode_frame_velo(ADSBFrame& frame, const uint32_t ICAO_address, const uint32_t speed, const float angle, const int32_t v_rate);

adsb_vel decode_frame_velo(ADSBFrame& frame);

// void encode_frame_emergency(ADSBFrame& frame, const uint32_t ICAO_address, const uint8_t code);

void encode_frame_squawk(ADSBFrame& frame, const uint16_t squawk);

} /* namespace adsb */

#endif /*__ADSB_H__*/