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use precision estimate from each OFDM symbol

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This commit is contained in:
Ahmet Inan 2022-05-18 12:24:32 +02:00
commit 8a9c7f29a2
1 changed files with 20 additions and 13 deletions
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33
decode.cc
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@ -501,23 +501,30 @@ struct Decoder
std::cerr << "coarse sfo: " << 1000000 * sfo_rad / Const::TwoPi() << " ppm" << std::endl;
std::cerr << "finer cfo: " << cfo_rad * (rate / Const::TwoPi()) << " Hz " << std::endl;
}
value precision = 16;
if (1) {
std::cerr << "Es/N0 (dB):";
value sp = 0, np = 0;
for (int i = 0; i < cons_cnt; ++i) {
code_type tmp[mod_max];
mod_hard(tmp, cons[i]);
cmplx hard = mod_map(tmp);
cmplx error = cons[i] - hard;
sp += norm(hard);
np += norm(error);
for (int j = 0; j < cons_rows; ++j) {
for (int i = 0; i < cons_cols; ++i) {
code_type tmp[mod_max];
mod_hard(tmp, cons[cons_cols*j+i]);
cmplx hard = mod_map(tmp);
cmplx error = cons[cons_cols*j+i] - hard;
sp += norm(hard);
np += norm(error);
}
value precision = sp / np;
value snr = DSP::decibel(precision);
std::cerr << " " << snr;
for (int i = 0; i < cons_cols; ++i)
mod_soft(code+mod_bits*(cons_cols*j+i), cons[cons_cols*j+i], precision);
}
precision = sp / np;
value snr = DSP::decibel(precision);
std::cerr << "init Es/N0: " << snr << " dB" << std::endl;
std::cerr << std::endl;
} else {
value precision = 8;
for (int i = 0; i < cons_cnt; ++i)
mod_soft(code+mod_bits*i, cons[i], precision);
}
for (int i = 0; i < cons_cnt; ++i)
mod_soft(code+mod_bits*i, cons[i], precision);
lengthen();
CODE::PolarHelper<mesg_type>::PATH metric[mesg_type::SIZE];
polardec(metric, mesg, code, frozen_bits, code_order);