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This commit is contained in:
Ahmet Inan 2025-07-17 15:47:06 +02:00
commit bca52ea9e8
3 changed files with 80 additions and 47 deletions
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25
encode.cc
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@ -34,7 +34,7 @@ struct Encoder : public Common
DSP::FastFourierTransform<symbol_len, cmplx, -1> fwd;
DSP::FastFourierTransform<symbol_len, cmplx, 1> bwd;
CODE::PolarEncoder<code_type> polar_encoder;
code_type code[bits_max], perm[bits_max], mesg[bits_max];
code_type code[bits_max], perm[bits_max], mesg[bits_max], meta[256];
cmplx fdom[symbol_len];
cmplx tdom[symbol_len];
cmplx best[symbol_len];
@ -82,14 +82,13 @@ struct Encoder : public Common
for (int i = 0; differential && symbol_number > 0 && i < tone_count; ++i)
tone[i] *= prev[i];
value best_papr = 1000;
int trials = symbol_number ? 4096 : 512;
CODE::XorShiftMask<int, 14, 1, 5, 10, 1> combination;
for (int trial = 0; trial < trials; ++trial) {
for (int trial = 0; trial < 4096; ++trial) {
for (int i = 0; i < tone_count; ++i)
temp[i] = tone[i];
if (symbol_number >= 0) {
int comb = combination();
int head_data = symbol_number ? trial >> 6 : (oper_mode << 3) | (trial >> 6);
int head_data = trial >> 6;
hadamard_encoder(head, head_data);
int tail_data = trial & 63;
hadamard_encoder(tail, tail_data);
@ -173,6 +172,17 @@ struct Encoder : public Common
symbol(-2);
symbol(-1);
}
void meta_data(uint64_t md)
{
for (int i = 0; i < 55; ++i)
mesg[i] = nrz((md >> i) & 1);
crc0.reset();
crc0(md << 9);
for (int i = 0; i < 16; ++i)
mesg[i+55] = nrz((crc0() >> i) & 1);
polar_encoder(code, mesg, frozen_256_71, 8);
shuffle(meta, code, 8);
}
cmplx map_bits(code_type *b, int bits)
{
switch (bits) {
@ -255,6 +265,7 @@ struct Encoder : public Common
int offset = (freq_off * symbol_len) / rate;
tone_off = offset - tone_count / 2;
guard_interval_weights();
meta_data(oper_mode);
leading_noise();
for (int input_index = 0; input_index < input_count; ++input_index) {
const char *input_name = input_names[input_index];
@ -281,13 +292,13 @@ struct Encoder : public Common
polar_encoder(code, mesg, frozen_bits, code_order);
shuffle(perm, code, code_order);
CODE::MLS seq1(mls1_poly);
for (int j = 0, k = 0; j < symbol_count; ++j) {
for (int j = 0, k = 0, m = 0; j < symbol_count + 1; ++j) {
head_off = (block_skew * j + first_head) % block_length;
tail_off = (block_skew * j + first_tail) % block_length;
for (int i = 0; i < tone_count; ++i) {
if (i % block_length == head_off || i % block_length == tail_off) {
tone[i] = nrz(seq1());
} else {
} else if (j) {
int bits = mod_bits;
if (oper_mode == 2 && k % 32 == 30)
bits = 2;
@ -295,6 +306,8 @@ struct Encoder : public Common
bits = 4;
tone[i] = map_bits(perm+k, bits);
k += bits;
} else {
tone[i] = map_bits(meta+m++, 1);
}
}
symbol(j);