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send meta data with each symbol

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This commit is contained in:
Ahmet Inan 2025-07-09 10:43:15 +02:00
commit b9d060ad22
3 changed files with 17 additions and 14 deletions
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19
decode.cc
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@ -233,8 +233,8 @@ struct Decoder : Common
CODE::MLS seq1(mls1_poly);
auto clamp = [](int v){ return v < -127 ? -127 : v > 127 ? 127 : v; };
for (int i = 0; i < pilot_tones; ++i)
mode[i] = clamp(std::nearbyint(127 * demod_or_erase(fdom[bin(i*block_length+first_pilot+tone_off)], chan[i*block_length+first_pilot]).real() * nrz(seq1())));
int oper_mode = hadamard_decoder(mode);
meta[i] = clamp(std::nearbyint(127 * demod_or_erase(fdom[bin(i*block_length+first_pilot+tone_off)], chan[i*block_length+first_pilot]).real() * nrz(seq1())));
int oper_mode = hadamard_decoder(meta);
if (oper_mode < 0 || oper_mode > 27) {
std::cerr << "operation mode " << oper_mode << " unsupported." << std::endl;
continue;
@ -264,17 +264,22 @@ struct Decoder : Common
} else {
for (int i = 0; i < symbol_pos+symbol_len+extended_len; ++i)
correlator(buf = next_sample());
hadamard_encoder(mode, oper_mode);
for (int i = 0; i < tone_count; ++i)
tone[i] = fdom[bin(i+tone_off)];
for (int i = 0; i < pilot_tones; ++i)
tone[block_length*i+pilot_off] *= mode[i];
seq1.reset();
}
for (int i = 0; i < tone_count; ++i)
tone[i] = fdom[bin(i+tone_off)];
for (int i = 0; i < pilot_tones; ++i)
tone[block_length*i+pilot_off] *= nrz(seq1());
for (int i = 0; i < tone_count; ++i)
demod[i] = demod_or_erase(tone[i], chan[i]);
for (int i = 0; i < pilot_tones; ++i)
meta[i] = clamp(std::nearbyint(127 * demod[i*block_length+pilot_off].real()));
int meta_data = hadamard_decoder(meta);
hadamard_encoder(meta, meta_data);
for (int i = 0; i < pilot_tones; ++i) {
tone[block_length*i+pilot_off] *= meta[i];
demod[block_length*i+pilot_off] *= meta[i];
}
for (int i = 0; i < pilot_tones; ++i) {
index[i] = tone_off + block_length * i + pilot_off;
phase[i] = arg(demod[block_length*i+pilot_off]);