m17.h

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#ifndef M17_CONSTS
#define M17_CONSTS

#ifdef __cplusplus
extern "C" {
#endif
#define FLT_LEN             81          //baseband filter length (number of taps)
#define SW_LEN              80          //syncword detector length
#define XC_LEN              90          //cross-correlator lookback length in samples
#define SYM_PER_SWD         8           //symbols per syncword
#define SYM_PER_PLD         184         //symbols per payload in a frame
#define SYM_PER_FRA         192         //symbols per whole 40 ms frame
#define RRC_DEV             7168.0f     //.rrc file deviation for +1.0 symbol

#define XCORR_THRESH            0.90            //arbitrary threshold between 0 and 1
#define SW_MEAN                         -0.75           //mean(str_sync)=mean(pkt_sync)
#define SW_STD                          8.21583836f     //std(str_sync)*sqrt(length(str_sync)-1)
#define DIST_THRESH         2.0f        //threshold for distance (syncword detection)

//syncword patterns (RX) TODO:Compute those at runtime from the consts below
const int8_t lsf_sync[8]={+3, +3, +3, +3, -3, -3, +3, -3};
const int8_t str_sync[8]={-3, -3, -3, -3, +3, +3, -3, +3};
const int8_t pkt_sync[8]={+3, -3, +3, +3, -3, -3, -3, -3};

//symbol levels (RX)
const float symbs[4]={-3.0, -1.0, +1.0, +3.0};

//dibits-symbols map (TX)
const int8_t symbol_map[4]={+1, +3, -1, -3};

//syncwords
const uint16_t SYNC_LSF = 0x55F7;
const uint16_t SYNC_STR = 0xFF5D;
const uint16_t SYNC_PKT = 0x75FF;
const uint16_t SYNC_BER = 0xDF55;
const uint16_t EOT_MRKR = 0x555D;

//puncturing pattern P_1
const uint8_t P_1[61]={1,1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,
                         1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,
                         1,0,1,1,1,0,1,1,1,0,1,1,1,0,1,1,
                         1,0,1,1,1,0,1,1,1,0,1,1};

//puncturing pattern P_2
const uint8_t P_2[12]={1,1,1,1,1,1,1,1,1,1,1,0};

//puncturing pattern P_3
const uint8_t P_3[8]={1,1,1,1,1,1,1,0};

//RRC filter - 10 samples per symbol, 8 symbols span
const float taps[FLT_LEN]=
{
            -0.003195702904062073f, -0.002930279157647190f, -0.001940667871554463f,
            -0.000356087678023658f,  0.001547011339077758f,  0.003389554791179751f,
             0.004761898604225673f,  0.005310860846138910f,  0.004824746306020221f,
             0.003297923526848786f,  0.000958710871218619f, -0.001749908029791816f,
            -0.004238694106631223f, -0.005881783042101693f, -0.006150256456781309f,
            -0.004745376707651645f, -0.001704189656473565f,  0.002547854551539951f,
             0.007215575568844704f,  0.011231038205363532f,  0.013421952197060707f,
             0.012730475385624438f,  0.008449554307303753f,  0.000436744366018287f,
            -0.010735380379191660f, -0.023726883538258272f, -0.036498030780605324f,
            -0.046500883189991064f, -0.050979050575999614f, -0.047340680079891187f,
            -0.033554880492651755f, -0.008513823955725943f,  0.027696543159614194f,
             0.073664520037517042f,  0.126689053778116234f,  0.182990955139333916f,
             0.238080025892859704f,  0.287235637987091563f,  0.326040247765297220f,
             0.350895727088112619f,  0.359452932027607974f,  0.350895727088112619f,
             0.326040247765297220f,  0.287235637987091563f,  0.238080025892859704f,
             0.182990955139333916f,  0.126689053778116234f,  0.073664520037517042f,
             0.027696543159614194f, -0.008513823955725943f, -0.033554880492651755f,
            -0.047340680079891187f, -0.050979050575999614f, -0.046500883189991064f,
            -0.036498030780605324f, -0.023726883538258272f, -0.010735380379191660f,
             0.000436744366018287f,  0.008449554307303753f,  0.012730475385624438f,
             0.013421952197060707f,  0.011231038205363532f,  0.007215575568844704f,
             0.002547854551539951f, -0.001704189656473565f, -0.004745376707651645f,
            -0.006150256456781309f, -0.005881783042101693f, -0.004238694106631223f,
            -0.001749908029791816f,  0.000958710871218619f,  0.003297923526848786f,
             0.004824746306020221f,  0.005310860846138910f,  0.004761898604225673f,
             0.003389554791179751f,  0.001547011339077758f, -0.000356087678023658f,
            -0.001940667871554463f, -0.002930279157647190f, -0.003195702904062073f
};

//randomizing pattern
const uint8_t rand_seq[46]=
{
    0xD6, 0xB5, 0xE2, 0x30, 0x82, 0xFF, 0x84, 0x62, 0xBA, 0x4E, 0x96, 0x90, 0xD8, 0x98, 0xDD, 0x5D, 0x0C, 0xC8, 0x52, 0x43, 0x91, 0x1D, 0xF8,
    0x6E, 0x68, 0x2F, 0x35, 0xDA, 0x14, 0xEA, 0xCD, 0x76, 0x19, 0x8D, 0xD5, 0x80, 0xD1, 0x33, 0x87, 0x13, 0x57, 0x18, 0x2D, 0x29, 0x78, 0xC3
};

//interleaver pattern
const uint16_t intrl_seq[368]=
{
        0, 137, 90, 227, 180, 317, 270, 39, 360, 129, 82, 219, 172, 309, 262, 31,
        352, 121, 74, 211, 164, 301, 254, 23, 344, 113, 66, 203, 156, 293, 246, 15,
        336, 105, 58, 195, 148, 285, 238, 7, 328, 97, 50, 187, 140, 277, 230, 367,
        320, 89, 42, 179, 132, 269, 222, 359, 312, 81, 34, 171, 124, 261, 214, 351,
        304, 73, 26, 163, 116, 253, 206, 343, 296, 65, 18, 155, 108, 245, 198, 335,
        288, 57, 10, 147, 100, 237, 190, 327, 280, 49, 2, 139, 92, 229, 182, 319,
        272, 41, 362, 131, 84, 221, 174, 311, 264, 33, 354, 123, 76, 213, 166, 303,
        256, 25, 346, 115, 68, 205, 158, 295, 248, 17, 338, 107, 60, 197, 150, 287,
        240, 9, 330, 99, 52, 189, 142, 279, 232, 1, 322, 91, 44, 181, 134, 271,
        224, 361, 314, 83, 36, 173, 126, 263, 216, 353, 306, 75, 28, 165, 118, 255,
        208, 345, 298, 67, 20, 157, 110, 247, 200, 337, 290, 59, 12, 149, 102, 239,
        192, 329, 282, 51, 4, 141, 94, 231, 184, 321, 274, 43, 364, 133, 86, 223,
        176, 313, 266, 35, 356, 125, 78, 215, 168, 305, 258, 27, 348, 117, 70, 207,
        160, 297, 250, 19, 340, 109, 62, 199, 152, 289, 242, 11, 332, 101, 54, 191,
        144, 281, 234, 3, 324, 93, 46, 183, 136, 273, 226, 363, 316, 85, 38, 175,
        128, 265, 218, 355, 308, 77, 30, 167, 120, 257, 210, 347, 300, 69, 22, 159,
        112, 249, 202, 339, 292, 61, 14, 151, 104, 241, 194, 331, 284, 53, 6, 143,
        96, 233, 186, 323, 276, 45, 366, 135, 88, 225, 178, 315, 268, 37, 358, 127,
        80, 217, 170, 307, 260, 29, 350, 119, 72, 209, 162, 299, 252, 21, 342, 111,
        64, 201, 154, 291, 244, 13, 334, 103, 56, 193, 146, 283, 236, 5, 326, 95,
        48, 185, 138, 275, 228, 365, 318, 87, 40, 177, 130, 267, 220, 357, 310, 79,
        32, 169, 122, 259, 212, 349, 302, 71, 24, 161, 114, 251, 204, 341, 294, 63,
        16, 153, 106, 243, 196, 333, 286, 55, 8, 145, 98, 235, 188, 325, 278, 47
};
#ifdef __cplusplus
}
#endif

#endif