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added nrz() helper function

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This commit is contained in:
Ahmet Inan 2021-06-13 14:19:46 +02:00
commit c87bfc6e78
2 changed files with 19 additions and 11 deletions
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12
decode.cc
View file

@ -204,13 +204,17 @@ struct Decoder
{
return (carrier + symbol_len) % symbol_len;
}
static int nrz(bool bit)
{
return 1 - 2 * bit;
}
const cmplx *mls0_seq()
{
CODE::MLS seq0(mls0_poly);
for (int i = 0; i < symbol_len/2; ++i)
fdom[i] = 0;
for (int i = 0; i < mls0_len; ++i)
fdom[(i+mls0_off/2+symbol_len/2)%(symbol_len/2)] = 1 - 2 * seq0();
fdom[(i+mls0_off/2+symbol_len/2)%(symbol_len/2)] = nrz(seq0());
return fdom;
}
int displacement(const cmplx *sym0, const cmplx *sym1)
@ -298,7 +302,7 @@ struct Decoder
fwd(fdom, tdom);
CODE::MLS seq1(mls1_poly);
for (int i = 0; i < mls1_len; ++i)
fdom[bin(i+mls1_off)] *= (1 - 2 * seq1());
fdom[bin(i+mls1_off)] *= nrz(seq1());
int8_t soft[mls1_len];
uint8_t data[(mls1_len+7)/8];
for (int i = 0; i < mls1_len; ++i)
@ -362,7 +366,7 @@ struct Decoder
fwd(fdom, cur += symbol_len+guard_len);
for (int i = 0; i < code_cols; ++i) {
cmplx con = fdom[bin(i+code_off)] / head[bin(i+code_off)];
cons[code_cols*j+i] = cmplx(con.real() * (1 - 2 * seq3()), con.imag() * (1 - 2 * seq4()));
cons[code_cols*j+i] = cmplx(con.real() * nrz(seq3()), con.imag() * nrz(seq4()));
}
}
value precision = 16;
@ -395,7 +399,7 @@ struct Decoder
for (int i = 0; i < cons_cnt; ++i) {
int8_t tmp[Mod::BITS];
for (int k = 0; k < Mod::BITS; ++k)
tmp[k] = 1 - 2 * (bint[Mod::BITS*i+k] < 0);
tmp[k] = nrz(bint[Mod::BITS*i+k] < 0);
cmplx hard = Mod::map(tmp);
cmplx error = cons[i] - hard;
sp += norm(hard);

18
encode.cc
View file

@ -60,6 +60,10 @@ struct Encoder
{
return (carrier + symbol_len) % symbol_len;
}
static int nrz(bool bit)
{
return 1 - 2 * bit;
}
void symbol()
{
bwd(tdom, fdom);
@ -96,7 +100,7 @@ struct Encoder
for (int i = code_off; i < code_off + code_cols; ++i) {
int8_t tmp[Mod::BITS];
for (int k = 0; k < Mod::BITS; ++k)
tmp[k] = 1 - 2 * seq2();
tmp[k] = nrz(seq2());
fdom[bin(i)] = code_fac * Mod::map(tmp);
}
symbol();
@ -109,7 +113,7 @@ struct Encoder
fdom[i] = 0;
fdom[bin(mls0_off-2)] = mls0_fac;
for (int i = 0; i < mls0_len; ++i)
fdom[bin(2*i+mls0_off)] = (1 - 2 * seq0());
fdom[bin(2*i+mls0_off)] = nrz(seq0());
for (int i = 0; i < mls0_len; ++i)
fdom[bin(2*i+mls0_off)] *= fdom[bin(2*(i-1)+mls0_off)];
symbol();
@ -130,13 +134,13 @@ struct Encoder
fdom[i] = 0;
fdom[bin(mls1_off-1)] = mls1_fac;
for (int i = 0; i < 71; ++i)
fdom[bin(i+mls1_off)] = (1 - 2 * CODE::get_be_bit(data, i));
fdom[bin(i+mls1_off)] = nrz(CODE::get_be_bit(data, i));
for (int i = 71; i < mls1_len; ++i)
fdom[bin(i+mls1_off)] = (1 - 2 * CODE::get_be_bit(parity, i-71));
fdom[bin(i+mls1_off)] = nrz(CODE::get_be_bit(parity, i-71));
for (int i = 0; i < mls1_len; ++i)
fdom[bin(i+mls1_off)] *= fdom[bin(i-1+mls1_off)];
for (int i = 0; i < mls1_len; ++i)
fdom[bin(i+mls1_off)] *= (1 - 2 * seq4());
fdom[bin(i+mls1_off)] *= nrz(seq4());
symbol();
}
void interleave()
@ -173,14 +177,14 @@ struct Encoder
inp[data_bits/8+i] = (crc1() >> (8*i)) & 255;
bchenc1(inp, inp+(data_bits+32)/8, data_bits+32);
for (int i = 0; i < data_bits+32+12*16; ++i)
code[i] = 1 - 2 * CODE::get_le_bit(inp, i);
code[i] = nrz(CODE::get_le_bit(inp, i));
ldpcenc(code, code+data_bits+32+12*16);
interleave();
CODE::MLS seq3(mls3_poly), seq4(mls4_poly);
for (int j = 0; j < code_rows; ++j) {
for (int i = 0; i < code_cols; ++i) {
cmplx con = Mod::map(bint+Mod::BITS*(code_cols*j+i));
con = cmplx(con.real() * (1 - 2 * seq3()), con.imag() * (1 - 2 * seq4()));
con = cmplx(con.real() * nrz(seq3()), con.imag() * nrz(seq4()));
fdom[bin(i+code_off)] *= con;
}
symbol();