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interleave reserved tones with data subcarriers

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This commit is contained in:
Ahmet Inan 2025-06-30 21:47:08 +02:00
commit efe5b9421d
2 changed files with 31 additions and 24 deletions
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24
encode.cc
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@ -38,10 +38,11 @@ struct Encoder
static const int mls2_poly = 0b100101010001;
static const int code_cols = 256;
static const int comb_cols = 32;
static const int cons_cols = code_cols + comb_cols;
static const int comb_dist = 9;
static const int comb_off = 4;
static const int reserved_tones = 32;
static const int cons_cols = code_cols + comb_cols + reserved_tones;
static const int block_len = 10;
static const int comb_off = 4;
static const int tone_off = 9;
DSP::WritePCM<value> *pcm;
DSP::FastFourierTransform<symbol_len, cmplx, -1> fwd;
DSP::FastFourierTransform<symbol_len, cmplx, 1> bwd;
@ -293,12 +294,12 @@ struct Encoder
void tone_reservation_kernels()
{
value mag = 1 / value(10 * reserved_tones);
for (int i = 0, j = cons_off - reserved_tones / 2; i < reserved_tones; ++i, ++j) {
if (j == cons_off)
j += cons_cols;
temp[bin(j)] = mag;
}
for (int i = 0; i < reserved_tones; ++i)
temp[bin(i*block_len+tone_off)] = mag;
bwd(kern, temp);
}
void guard_interval_weights()
{
for (int i = 0; i < guard_len / 4; ++i)
weight[i] = 0;
for (int i = guard_len / 4; i < guard_len / 4 + guard_len / 2; ++i) {
@ -313,6 +314,7 @@ struct Encoder
{
setup(oper_mode, freq_off);
tone_reservation_kernels();
guard_interval_weights();
papr_min = 1000, papr_max = -1000;
pilot_block();
hadamardenc(mode, oper_mode);
@ -320,7 +322,7 @@ struct Encoder
schmidl_cox();
CODE::MLS seq1(mls1_poly);
for (int i = 0, m = 0; i < cons_cols; ++i) {
if (i % comb_dist == comb_off) {
if (i % block_len == comb_off) {
cons[i] = nrz(seq1()) * mode[m++];
} else {
cons[i] = 0;
@ -355,8 +357,10 @@ struct Encoder
CODE::MLS seq1(mls1_poly);
for (int j = 0, k = 0; j < cons_rows; ++j) {
for (int i = 0, m = 0; i < cons_cols; ++i) {
if (i % comb_dist == comb_off) {
if (i % block_len == comb_off) {
cons[i] = nrz(seq1()) * mode[m++];
} else if (i % block_len == tone_off) {
cons[i] = 0;
} else {
cons[i] = mod_map(perm+k);
k += mod_bits;