Mirror/aicodix___modem
1
0
Fork 0
mirror of https://github.com/aicodix/modem.git synced 2026-04-27 14:30:34 +00:00
Code Issues Projects Releases Packages Wiki Activity

try to improve papr of first symbol

Browse source
This commit is contained in:
Ahmet Inan 2025-07-10 19:06:02 +02:00
commit e5801a698e
2 changed files with 5 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

2
decode.cc
View file

@ -234,7 +234,7 @@ struct Decoder : Common
auto clamp = [](int v){ return v < -127 ? -127 : v > 127 ? 127 : v; };
for (int i = 0; i < pilot_tones; ++i)
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 mode = hadamard_decoder(meta);
int mode = hadamard_decoder(meta) & 31;
if (mode < 0 || mode > 27) {
std::cerr << "operation mode " << mode << " unsupported." << std::endl;
continue;

7
encode.cc
View file

@ -73,11 +73,12 @@ struct Encoder : public Common
{
for (int i = 0; differential && symbol_number > 0 && i < tone_count; ++i)
tone[i] *= temp[i];
for (int trial = 63; trial >= 0; --trial) {
int trials = symbol_number ? 128 : 4;
for (int trial = trials - 1; trial >= 0; --trial) {
for (int i = 0; i < tone_count; ++i)
temp[i] = tone[i];
if (symbol_number >= 0) {
int meta_data = symbol_number ? trial : oper_mode;
int meta_data = symbol_number ? trial : (oper_mode | (trial << 5));
hadamard_encoder(meta, meta_data);
CODE::MLS seq(0x163, meta_data);
for (int i = 0, m = 0; i < tone_count; ++i)
@ -110,7 +111,7 @@ struct Encoder : public Common
}
mean /= symbol_len;
value papr(peak / mean);
if (symbol_number == 0 || papr < 5 || trial == 0) {
if (papr < 5 || trial == 0) {
std::cerr << " " << DSP::decibel(papr);
break;
}