Sylvain Munaut | ce7be3a | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 1 | /* |
| 2 | * gps.h |
| 3 | * |
| 4 | * Header to deal with low level GPS data |
| 5 | * |
| 6 | * |
| 7 | * Copyright (C) 2009 Sylvain Munaut <tnt@246tNt.com> |
| 8 | * |
| 9 | * This program is free software: you can redistribute it and/or modify |
| 10 | * it under the terms of the GNU General Public License as published by |
| 11 | * the Free Software Foundation, either version 2 of the License, or |
| 12 | * (at your option) any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 21 | */ |
| 22 | |
| 23 | #ifndef __GPS_H__ |
| 24 | #define __GPS_H__ |
| 25 | |
| 26 | #ifdef __cplusplus |
| 27 | extern "C" { |
| 28 | #endif |
| 29 | |
| 30 | #include <stdint.h> |
| 31 | |
| 32 | |
| 33 | #define MAX_SV 64 |
| 34 | |
| 35 | |
| 36 | /* Ionosperic model data */ |
| 37 | struct gps_ionosphere_model { |
| 38 | /* #bits Scale factor Effective Units */ |
| 39 | /* (LSB) range */ |
| 40 | |
| 41 | int alpha_0; /* s 8 2^-30 seconds */ |
| 42 | int alpha_1; /* s 8 2^-27 s / semi-circles */ |
| 43 | int alpha_2; /* s 8 2^-24 s / (semi-circles)^2 */ |
| 44 | int alpha_3; /* s 8 2^-24 s / (semi-circles)^3 */ |
| 45 | int beta_0; /* s 8 2^11 seconds */ |
| 46 | int beta_1; /* s 8 2^14 s / semi-circles */ |
| 47 | int beta_2; /* s 8 2^16 s / (semi-circles)^2 */ |
| 48 | int beta_3; /* s 8 2^16 s / (semi-circles)^3 */ |
| 49 | }; |
| 50 | |
| 51 | |
| 52 | /* UTC model data */ |
| 53 | struct gps_utc_model { |
| 54 | /* #bits Scale factor Effective Units */ |
| 55 | /* (LSB) range */ |
| 56 | |
| 57 | int a0; /* s 32 2^-30 seconds */ |
| 58 | int a1; /* s 24 2^-50 seconds / seconds */ |
| 59 | int delta_t_ls; /* s 8 1 seconds */ |
| 60 | int t_ot; /* u 8 2^12 602,112 seconds */ |
| 61 | int wn_t; /* u 8 1 weeks */ |
| 62 | int wn_lsf; /* u 8 1 weeks */ |
| 63 | int dn; /* u 8 1 7 days */ |
| 64 | int delta_t_lsf;/* s 8 1 seconds */ |
| 65 | }; |
| 66 | |
| 67 | |
| 68 | /* Almanach data */ |
| 69 | struct gps_almanac_sv { |
| 70 | int sv_id; |
| 71 | int sv_health; |
| 72 | |
| 73 | /* #bits Scale factor Effective Units */ |
| 74 | /* (LSB) range */ |
| 75 | |
| 76 | int e; /* u 16 2^-21 */ |
| 77 | int t_oa; /* u 8 2^12 602,112 seconds */ |
| 78 | int ksii; /* s 16 2^-19 semi-circles */ |
| 79 | int omega_dot; /* s 16 2^-38 semi-circles / s */ |
| 80 | int a_powhalf; /* u 24 2^-11 meters */ |
| 81 | int omega_0; /* s 24 2^-23 semi-circles */ |
| 82 | int w; /* s 24 2^-23 semi-circles */ |
| 83 | int m_0; /* s 24 2^-23 semi-circles */ |
| 84 | int a_f0; /* s 11 2^-20 seconds */ |
| 85 | int a_f1; /* s 11 2^-38 seconds / seconds */ |
| 86 | }; |
| 87 | |
| 88 | struct gps_almanac { |
| 89 | int wna; |
| 90 | int n_sv; |
| 91 | struct gps_almanac_sv svs[MAX_SV]; |
| 92 | }; |
| 93 | |
| 94 | |
| 95 | /* Ephemeris data */ |
| 96 | struct gps_ephemeris_sv { |
| 97 | int sv_id; |
| 98 | |
| 99 | /* #bits Scale factor Effective Units */ |
| 100 | /* (LSB) range */ |
| 101 | |
| 102 | int code_on_l2; /* u 2 1 / */ |
| 103 | int week_no; /* u 10 1 week */ |
| 104 | int l2_p_flag; /* u 1 1 / */ |
| 105 | int sv_ura; /* u 4 / / */ |
| 106 | int sv_health; /* u 6 / / */ |
| 107 | int t_gd; /* s 8 2^-31 seconds */ |
| 108 | int iodc; /* u 10 / / */ |
| 109 | int t_oc; /* u 16 2^4 604,784 seconds */ |
| 110 | int a_f2; /* s 8 2^-55 sec / sec^2 */ |
| 111 | int a_f1; /* s 16 2^-43 sec / sec */ |
| 112 | int a_f0; /* s 22 2^-31 seconds */ |
| 113 | |
| 114 | int c_rs; /* s 16 2^-5 meters */ |
| 115 | int delta_n; /* s 16 2^-43 semi-circles / s */ |
Sylvain Munaut | d5d6e7f | 2009-12-28 00:30:02 +0100 | [diff] [blame] | 116 | int m_0; /* s 32 2^-31 semi-circles */ |
Sylvain Munaut | ce7be3a | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 117 | int c_uc; /* s 16 2^-29 radians */ |
| 118 | unsigned int e; /* u 32 2^-33 0.03 / */ |
| 119 | int c_us; /* s 16 2^-29 radians */ |
| 120 | unsigned int a_powhalf; /* u 32 2^-19 meters^(1/2) */ |
| 121 | int t_oe; /* u 16 2^4 604,784 seconds */ |
| 122 | int fit_flag; /* u 1 / / */ |
| 123 | |
| 124 | int c_ic; /* s 16 2^-29 radians */ |
| 125 | int omega_0; /* s 32 2^-31 semi-circles */ |
| 126 | int c_is; /* s 16 2^-29 radians */ |
| 127 | int i_0; /* s 32 2^-31 semi-circles */ |
| 128 | int c_rc; /* s 16 2^-5 meters */ |
| 129 | int w; /* s 32 2^-31 semi-circles */ |
| 130 | int omega_dot; /* s 24 2^-43 semi-circles / s */ |
| 131 | int idot; /* s 14 2^-43 semi-circles / s */ |
| 132 | |
| 133 | int _rsvd1; /* 23 bits */ |
| 134 | int _rsvd2; /* 24 bits */ |
| 135 | int _rsvd3; /* 24 bits */ |
| 136 | int _rsvd4; /* 16 bits */ |
| 137 | int aodo; /* 8 bits Not sure it needs to be here ... */ |
| 138 | }; |
| 139 | |
| 140 | struct gps_ephemeris { |
| 141 | int n_sv; |
| 142 | struct gps_ephemeris_sv svs[MAX_SV]; |
| 143 | }; |
| 144 | |
| 145 | |
Sylvain Munaut | 7a3e51f | 2009-12-28 14:31:41 +0100 | [diff] [blame] | 146 | /* Reference position */ |
| 147 | struct gps_ref_pos { /* WSG84 ellipsoid */ |
| 148 | double latitude; /* deg */ |
| 149 | double longitude; /* deg */ |
| 150 | double altitude; /* m above ellipsoid */ |
| 151 | }; |
| 152 | |
| 153 | |
Sylvain Munaut | ce7be3a | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 154 | /* All assist data */ |
| 155 | #define GPS_FIELD_IONOSPHERE (1<<0) |
| 156 | #define GPS_FIELD_UTC (1<<1) |
| 157 | #define GPS_FIELD_ALMANAC (1<<2) |
| 158 | #define GPS_FIELD_EPHEMERIS (1<<3) |
Sylvain Munaut | 7a3e51f | 2009-12-28 14:31:41 +0100 | [diff] [blame] | 159 | #define GPS_FIELD_REFPOS (1<<4) |
Sylvain Munaut | ce7be3a | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 160 | |
| 161 | struct gps_assist_data { |
| 162 | int fields; |
| 163 | struct gps_ionosphere_model ionosphere; |
| 164 | struct gps_utc_model utc; |
| 165 | struct gps_almanac almanac; |
| 166 | struct gps_ephemeris ephemeris; |
Sylvain Munaut | 7a3e51f | 2009-12-28 14:31:41 +0100 | [diff] [blame] | 167 | struct gps_ref_pos ref_pos; |
Sylvain Munaut | ce7be3a | 2009-12-22 21:53:22 +0100 | [diff] [blame] | 168 | }; |
| 169 | |
| 170 | |
| 171 | /* GPS Subframe utility methods (see gps.c for details) */ |
| 172 | int gps_unpack_sf123(uint32_t *sf, struct gps_ephemeris_sv *eph); |
| 173 | int gps_unpack_sf45_almanac(uint32_t *sf, struct gps_almanac_sv *alm); |
| 174 | |
| 175 | |
| 176 | #ifdef __cplusplus |
| 177 | } |
| 178 | #endif |
| 179 | |
| 180 | #endif /* __GPS_H__ */ |
| 181 | |