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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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2
common.hh
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@ -29,7 +29,7 @@ struct Common
static const int first_reserved = 9;
CODE::CRC<uint32_t> crc0;
CODE::HadamardEncoder<6> hadamard_encoder;
int8_t mode[32];
int8_t meta[32];
uint8_t data[data_max];
const uint32_t *frozen_bits;
int mod_bits;

19
decode.cc
View file

@ -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]);

10
encode.cc
View file

@ -251,7 +251,6 @@ struct Encoder : public Common
guard_interval_weights();
papr_min = 1000, papr_max = -1000;
leading_noise();
hadamard_encoder(mode, oper_mode);
for (int input_index = 0; input_index < input_count; ++input_index) {
const char *input_name = input_names[input_index];
if (input_count == 1 && input_name[0] == '-' && input_name[1] == 0)
@ -277,14 +276,13 @@ struct Encoder : public Common
polar_encoder(code, mesg, frozen_bits, code_order);
shuffle(perm, code);
CODE::MLS seq1(mls1_poly);
for (int j = 0, k = 0, m = 0; j < symbol_count; ++j) {
for (int j = 0, k = 0; j < symbol_count; ++j) {
pilot_off = (block_skew * j + first_pilot) % block_length;
reserved_off = (block_skew * j + first_reserved) % block_length;
for (int i = 0; i < tone_count; ++i) {
hadamard_encoder(meta, j ? j : oper_mode);
for (int i = 0, m = 0; i < tone_count; ++i) {
if (i % block_length == pilot_off) {
tone[i] = nrz(seq1());
if (j == 0)
tone[i] *= mode[m++];
tone[i] = nrz(seq1()) * meta[m++];
} else if (i % block_length == reserved_off) {
tone[i] = 0;
} else {