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#include "make_ccsds.h"
#include <cassert>
// Ported over from :
// https://github.com/daniestevez/ldpc-toolbox/blob/main/src/codes/ccsds.rs
namespace codings
{
namespace ldpc
{
namespace ccsds_ar4ja
{
void mtx_toggle(codings::ldpc::Sparse_matrix &m, size_t row, size_t col)
{
if (m.at(row, col))
m.rm_connection(row, col);
else
m.add_connection(row, col);
}
enum ar4ja_M_t
{
M128,
M256,
M512,
M1024,
M2048,
M4096,
M8192,
};
int mlog2(ar4ja_M_t v)
{
switch (v)
{
case M128:
return 7;
case M256:
return 8;
case M512:
return 9;
case M1024:
return 10;
case M2048:
return 11;
case M4096:
return 12;
case M8192:
return 13;
}
return 0;
}
ar4ja_M_t get_m(ar4ja_rate_t rate, ar4ja_blocksize_t k)
{
if (k == AR4JA_BLOCK_1024)
{
if (rate == AR4JA_RATE_1_2)
return M512;
else if (rate == AR4JA_RATE_2_3)
return M256;
else if (rate == AR4JA_RATE_4_5)
return M128;
}
else if (k == AR4JA_BLOCK_4096)
{
if (rate == AR4JA_RATE_1_2)
return M2048;
else if (rate == AR4JA_RATE_2_3)
return M1024;
else if (rate == AR4JA_RATE_4_5)
return M512;
}
else if (k == AR4JA_BLOCK_16384)
{
if (rate == AR4JA_RATE_1_2)
return M8192;
else if (rate == AR4JA_RATE_2_3)
return M4096;
else if (rate == AR4JA_RATE_4_5)
return M2048;
}
return M512;
}
uint8_t THETA_K[26] = {3, 0, 1, 2, 2, 3, 0, 1, 0, 1, 2, 0, 2, 3, 0, 1, 2, 0, 1, 2, 0, 1, 2, 1, 2, 3};
// Table 7-3 and 7-4 in [1]
size_t mtheta(size_t k)
{
assert(k <= 26);
return THETA_K[k - 1];
}
// Table 7-3 and 7-4 in [1]
size_t PHI_K[4][26][7] = {
// j = 0
{
{1, 59, 16, 160, 108, 226, 1148},
{22, 18, 103, 241, 126, 618, 2032},
{0, 52, 105, 185, 238, 404, 249},
{26, 23, 0, 251, 481, 32, 1807},
{0, 11, 50, 209, 96, 912, 485},
{10, 7, 29, 103, 28, 950, 1044},
{5, 22, 115, 90, 59, 534, 717},
{18, 25, 30, 184, 225, 63, 873},
{3, 27, 92, 248, 323, 971, 364},
{22, 30, 78, 12, 28, 304, 1926},
{3, 43, 70, 111, 386, 409, 1241},
{8, 14, 66, 66, 305, 708, 1769},
{25, 46, 39, 173, 34, 719, 532},
{25, 62, 84, 42, 510, 176, 768},
{2, 44, 79, 157, 147, 743, 1138},
{27, 12, 70, 174, 199, 759, 965},
{7, 38, 29, 104, 347, 674, 141},
{7, 47, 32, 144, 391, 958, 1527},
{15, 1, 45, 43, 165, 984, 505},
{10, 52, 113, 181, 414, 11, 1312},
{4, 61, 86, 250, 97, 413, 1840},
{19, 10, 1, 202, 158, 925, 709},
{7, 55, 42, 68, 86, 687, 1427},
{9, 7, 118, 177, 168, 752, 989},
{26, 12, 33, 170, 506, 867, 1925},
{17, 2, 126, 89, 489, 323, 270},
},
// j = 1
{
{0, 0, 0, 0, 0, 0, 0},
{27, 32, 53, 182, 375, 767, 1822},
{30, 21, 74, 249, 436, 227, 203},
{28, 36, 45, 65, 350, 247, 882},
{7, 30, 47, 70, 260, 284, 1989},
{1, 29, 0, 141, 84, 370, 957},
{8, 44, 59, 237, 318, 482, 1705},
{20, 29, 102, 77, 382, 273, 1083},
{26, 39, 25, 55, 169, 886, 1072},
{24, 14, 3, 12, 213, 634, 354},
{4, 22, 88, 227, 67, 762, 1942},
{12, 15, 65, 42, 313, 184, 446},
{23, 48, 62, 52, 242, 696, 1456},
{15, 55, 68, 243, 188, 413, 1940},
{15, 39, 91, 179, 1, 854, 1660},
{22, 11, 70, 250, 306, 544, 1661},
{31, 1, 115, 247, 397, 864, 587},
{3, 50, 31, 164, 80, 82, 708},
{29, 40, 121, 17, 33, 1009, 1466},
{21, 62, 45, 31, 7, 437, 433},
{2, 27, 56, 149, 447, 36, 1345},
{5, 38, 54, 105, 336, 562, 867},
{11, 40, 108, 183, 424, 816, 1551},
{26, 15, 14, 153, 134, 452, 2041},
{9, 11, 30, 177, 152, 290, 1383},
{17, 18, 116, 19, 492, 778, 1790},
},
// j = 2
{
{0, 0, 0, 0, 0, 0, 0},
{12, 46, 8, 35, 219, 254, 318},
{30, 45, 119, 167, 16, 790, 494},
{18, 27, 89, 214, 263, 642, 1467},
{10, 48, 31, 84, 415, 248, 757},
{16, 37, 122, 206, 403, 899, 1085},
{13, 41, 1, 122, 184, 328, 1630},
{9, 13, 69, 67, 279, 518, 64},
{7, 9, 92, 147, 198, 477, 689},
{15, 49, 47, 54, 307, 404, 1300},
{16, 36, 11, 23, 432, 698, 148},
{18, 10, 31, 93, 240, 160, 777},
{4, 11, 19, 20, 454, 497, 1431},
{23, 18, 66, 197, 294, 100, 659},
{5, 54, 49, 46, 479, 518, 352},
{3, 40, 81, 162, 289, 92, 1177},
{29, 27, 96, 101, 373, 464, 836},
{11, 35, 38, 76, 104, 592, 1572},
{4, 25, 83, 78, 141, 198, 348},
{8, 46, 42, 253, 270, 856, 1040},
{2, 24, 58, 124, 439, 235, 779},
{11, 33, 24, 143, 333, 134, 476},
{11, 18, 25, 63, 399, 542, 191},
{3, 37, 92, 41, 14, 545, 1393},
{15, 35, 38, 214, 277, 777, 1752},
{13, 21, 120, 70, 412, 483, 1627},
},
// j = 3
{
{0, 0, 0, 0, 0, 0, 0},
{13, 44, 35, 162, 312, 285, 1189},
{19, 51, 97, 7, 503, 554, 458},
{14, 12, 112, 31, 388, 809, 460},
{15, 15, 64, 164, 48, 185, 1039},
{20, 12, 93, 11, 7, 49, 1000},
{17, 4, 99, 237, 185, 101, 1265},
{4, 7, 94, 125, 328, 82, 1223},
{4, 2, 103, 133, 254, 898, 874},
{11, 30, 91, 99, 202, 627, 1292},
{17, 53, 3, 105, 285, 154, 1491},
{20, 23, 6, 17, 11, 65, 631},
{8, 29, 39, 97, 168, 81, 464},
{22, 37, 113, 91, 127, 823, 461},
{19, 42, 92, 211, 8, 50, 844},
{15, 48, 119, 128, 437, 413, 392},
{5, 4, 74, 82, 475, 462, 922},
{21, 10, 73, 115, 85, 175, 256},
{17, 18, 116, 248, 419, 715, 1986},
{9, 56, 31, 62, 459, 537, 19},
{20, 9, 127, 26, 468, 722, 266},
{18, 11, 98, 140, 209, 37, 471},
{31, 23, 23, 121, 311, 488, 1166},
{13, 8, 38, 12, 211, 179, 1300},
{2, 7, 18, 41, 510, 430, 1033},
{18, 24, 62, 249, 320, 264, 1606},
},
};
// Table 7-3 and 7-4 in [1]
size_t mphi(ar4ja_rate_t rate, ar4ja_blocksize_t bk, size_t k, size_t j)
{
assert(k <= 26);
assert(j <= 4);
int m_index = mlog2(get_m(rate, bk)) - mlog2(M128);
return PHI_K[j][k - 1][m_index];
}
// Section 7.4.2.4 in [1]
size_t mpi(ar4ja_rate_t rate, ar4ja_blocksize_t bk, size_t k, size_t i)
{
int m_log2 = mlog2(get_m(rate, bk));
int m = 1 << m_log2;
int j = 4 * i / m;
// & 0x3 gives mod 4
int a = (mtheta(k) + j) & 0x3;
int m_div_4 = 1 << (m_log2 - 2);
// & (m_div_4 - 1) gives mod M/4
int b = (mphi(rate, bk, k, j) + i) & (m_div_4 - 1);
// << (m_log2 - 2) gives * M/4
return (a << (m_log2 - 2)) + b;
}
codings::ldpc::Sparse_matrix make_ar4ja_code(ar4ja_rate_t rate, ar4ja_blocksize_t k, int *M)
{
int m = 1 << mlog2(get_m(rate, k));
int extra_column_blocks = 0;
if (rate == AR4JA_RATE_1_2)
extra_column_blocks = 0;
else if (rate == AR4JA_RATE_2_3)
extra_column_blocks = 2;
else if (rate == AR4JA_RATE_4_5)
extra_column_blocks = 6;
int extra_columns = m * extra_column_blocks;
codings::ldpc::Sparse_matrix h(3 * m, extra_columns + 5 * m);
// fill common part (H_1/2)
for (int i = 0; i < m; i++)
{
// block(0,2) = I_M
h.add_connection(i, extra_columns + 2 * m + i);
// block(0,4) = I_M + Pi_1
h.add_connection(i, extra_columns + 4 * m + i);
mtx_toggle(h, i, extra_columns + 4 * m + mpi(rate, k, 1, i));
// block(1,0) = I_M
h.add_connection(m + i, extra_columns + i);
// block(1,1) = I_M
h.add_connection(m + i, extra_columns + m + i);
// block(1,3) = I_M
h.add_connection(m + i, extra_columns + 3 * m + i);
// block(1,4) = Pi_2 + Pi_3 + Pi_4
h.add_connection(m + i, extra_columns + 4 * m + mpi(rate, k, 2, i));
mtx_toggle(h, m + i, extra_columns + 4 * m + mpi(rate, k, 3, i));
mtx_toggle(h, m + i, extra_columns + 4 * m + mpi(rate, k, 4, i));
// block(2,0) = I_M
h.add_connection(2 * m + i, extra_columns + i);
// block(2,1) = Pi_5 + Pi_6
h.add_connection(2 * m + i, extra_columns + m + mpi(rate, k, 5, i));
mtx_toggle(h, 2 * m + i, extra_columns + m + mpi(rate, k, 6, i));
// block(2,3) = Pi_7 + Pi_8
h.add_connection(2 * m + i, extra_columns + 3 * m + mpi(rate, k, 7, i));
mtx_toggle(h, 2 * m + i, extra_columns + 3 * m + mpi(rate, k, 8, i));
// block(2,4) = I_M
h.add_connection(2 * m + i, extra_columns + 4 * m + i);
}
if (rate != AR4JA_RATE_1_2)
{
// fill specific H_2/3 part
if (rate == AR4JA_RATE_2_3)
extra_columns = 0;
else if (rate == AR4JA_RATE_4_5)
extra_columns = 4 * m;
for (int i = 0; i < m; i++)
{
// block(1,0) = Pi_9 + Pi_10 + Pi_11
h.add_connection(m + i, extra_columns + mpi(rate, k, 9, i));
mtx_toggle(h, m + i, extra_columns + mpi(rate, k, 10, i));
mtx_toggle(h, m + i, extra_columns + mpi(rate, k, 11, i));
// block(1,1) = I_M
h.add_connection(m + i, extra_columns + m + i);
// block(2,0) = I_M
h.add_connection(2 * m + i, extra_columns + i);
// block(2,1) = Pi_12 + Pi_13 + Pi_14
h.add_connection(2 * m + i, extra_columns + m + mpi(rate, k, 12, i));
mtx_toggle(h, 2 * m + i, extra_columns + m + mpi(rate, k, 13, i));
mtx_toggle(h, 2 * m + i, extra_columns + m + mpi(rate, k, 14, i));
}
}
if (rate == AR4JA_RATE_4_5)
{
// fill specific H_4/5 part
for (int i = 0; i < m; i++)
{
// block(1,0) = Pi_21 + Pi_22 + Pi_23
h.add_connection(m + i, mpi(rate, k, 21, i));
mtx_toggle(h, m + i, mpi(rate, k, 22, i));
mtx_toggle(h, m + i, mpi(rate, k, 23, i));
// block(1,1) = I_M
h.add_connection(m + i, m + i);
// block(1,2) = Pi_15 + Pi_16 + Pi_17
h.add_connection(m + i, 2 * m + mpi(rate, k, 15, i));
mtx_toggle(h, m + i, 2 * m + mpi(rate, k, 16, i));
mtx_toggle(h, m + i, 2 * m + mpi(rate, k, 17, i));
// block(1,3) = I_M
h.add_connection(m + i, 3 * m + i);
// block(2,0) = I_M
h.add_connection(2 * m + i, i);
// block(2,1) = Pi_24 + Pi_25 + Pi_26
h.add_connection(2 * m + i, m + mpi(rate, k, 24, i));
mtx_toggle(h, 2 * m + i, m + mpi(rate, k, 25, i));
mtx_toggle(h, 2 * m + i, m + mpi(rate, k, 26, i));
// block(2,2) = I_M
h.add_connection(2 * m + i, 2 * m + i);
// block(2,3) = Pi_18 + Pi_19 + Pi_20
h.add_connection(2 * m + i, 3 * m + mpi(rate, k, 18, i));
mtx_toggle(h, 2 * m + i, 3 * m + mpi(rate, k, 19, i));
mtx_toggle(h, 2 * m + i, 3 * m + mpi(rate, k, 20, i));
}
}
if (M != nullptr)
*M = m;
return h;
}
}
namespace ccsds_78
{
/* (8176, 7154) code Parity Check Matrix dimensions */
const size_t pcm_8176_7154_w = 8176;
const size_t pcm_8176_7154_h = 1022;
const size_t pcm_8176_7154_max_deg = 32;
const size_t pcm_8176_7154_edges = 32704;
/* (8176, 7154) code subblock characteristics of the parity check matrix */
const size_t pcm_8176_7154_sb_x = 16; // subblocks in x dimension
const size_t pcm_8176_7154_sb_y = 2; // subblocks in y dimension
const size_t pcm_8176_7154_sb_size = 511; // subblock size (subblocks are square)
const size_t pcm_8176_7154_row_deg = 32; // All rows have the same degree
/* (8176, 7154) code parity check matrix circulants.
* Each row of a subblock has exactly 2 non-zero element */
const uint16_t pcm_8176_7154_circulants[pcm_8176_7154_sb_y][pcm_8176_7154_sb_x][2] = {{{0, 176},
{12, 239},
{0, 352},
{24, 431},
{0, 392},
{151, 409},
{0, 351},
{9, 359},
{0, 307},
{53, 329},
{0, 207},
{18, 281},
{0, 399},
{202, 457},
{0, 247},
{36, 261}},
{{99, 471},
{130, 473},
{198, 435},
{260, 478},
{215, 420},
{282, 481},
{48, 396},
{193, 445},
{273, 430},
{302, 451},
{96, 379},
{191, 386},
{244, 467},
{364, 470},
{51, 382},
{192, 414}}};
codings::ldpc::Sparse_matrix make_r78_code()
{
/* Subblocks are square */
const size_t subblock_size = pcm_8176_7154_sb_size;
const size_t subblocks_x = pcm_8176_7154_sb_x;
const size_t subblocks_y = pcm_8176_7154_sb_y;
size_t abs_row;
uint16_t rel_offset0, rel_offset1;
uint16_t abs_offset0, abs_offset1;
codings::ldpc::Sparse_matrix r78(pcm_8176_7154_h, pcm_8176_7154_w);
for (size_t sblk_y = 0; sblk_y < subblocks_y; sblk_y++)
{
for (size_t row = 0; row < subblock_size; row++)
{
abs_row = sblk_y * subblock_size + row;
for (size_t sblk_x = 0; sblk_x < subblocks_x; sblk_x++)
{
rel_offset0 = pcm_8176_7154_circulants[sblk_y][sblk_x][0];
rel_offset1 = pcm_8176_7154_circulants[sblk_y][sblk_x][1];
/* Compute the final absolute offsets of '1's in the
* current circulant depending on the current row and
* subblock. */
rel_offset0 = (rel_offset0 + row) % subblock_size;
rel_offset1 = (rel_offset1 + row) % subblock_size;
abs_offset0 = subblock_size * sblk_x + rel_offset0;
abs_offset1 = subblock_size * sblk_x + rel_offset1;
r78.add_connection(abs_row, abs_offset0);
r78.add_connection(abs_row, abs_offset1);
}
}
}
return r78;
}
}
}
}
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