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added bpsk and qpsk types to reduce code

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This commit is contained in:
Ahmet Inan 2023-05-12 09:42:19 +02:00
commit a9e221adf1
2 changed files with 10 additions and 25 deletions
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27
decode.cc
View file

@ -167,9 +167,10 @@ struct Decoder
typedef SIMD<code_type, 16 / sizeof(code_type)> mesg_type;
#endif
typedef DSP::Const<value> Const;
typedef PhaseShiftKeying<2, cmplx, code_type> bpsk;
typedef PhaseShiftKeying<4, cmplx, code_type> qpsk;
static const int sample_rate = 8000;
static const int code_order = 12;
static const int mod_bits = 2;
static const int code_len = 1 << code_order;
static const int meta_len = 63;
static const int symbol_len = 256;
@ -236,18 +237,6 @@ struct Decoder
if (!((frozen_bits[i/32] >> (i%32)) & 1))
mesg[j++] = mess[i];
}
cmplx mod_map(code_type *b)
{
return PhaseShiftKeying<4, cmplx, code_type>::map(b);
}
void mod_hard(code_type *b, cmplx c)
{
PhaseShiftKeying<4, cmplx, code_type>::hard(b, c);
}
void mod_soft(code_type *b, cmplx c, value precision)
{
PhaseShiftKeying<4, cmplx, code_type>::soft(b, c, precision);
}
const cmplx *next_sample()
{
value real;
@ -290,7 +279,7 @@ struct Decoder
for (int i = 0; i < subcarrier_count; ++i)
prev[i] = fdom[bin(i)];
for (int i = 0; i < meta_len; ++i)
code[i] = DSP::clamp<value>(16 * cons[i].real(), -127, 127);
bpsk::soft(code+i, cons[i], 8);
CODE::MLS seq(0b1000011);
for (int i = 0; i < meta_len; ++i)
code[i] *= nrz(seq());
@ -327,9 +316,9 @@ struct Decoder
value sp = 0, np = 0;
for (int j = 0; j < payload_symbols; ++j) {
for (int i = 0; i < subcarrier_count; ++i) {
code_type tmp[mod_bits];
mod_hard(tmp, cons[subcarrier_count*j+i]);
cmplx hard = mod_map(tmp);
code_type tmp[2];
qpsk::hard(tmp, cons[subcarrier_count*j+i]);
cmplx hard = qpsk::map(tmp);
cmplx error = cons[subcarrier_count*j+i] - hard;
sp += norm(hard);
np += norm(error);
@ -338,13 +327,13 @@ struct Decoder
value snr = DSP::decibel(precision);
std::cerr << " " << snr;
for (int i = 0; i < subcarrier_count; ++i)
mod_soft(code+mod_bits*(subcarrier_count*j+i), cons[subcarrier_count*j+i], precision);
qpsk::soft(code+2*(subcarrier_count*j+i), cons[subcarrier_count*j+i], precision);
}
std::cerr << std::endl;
} else {
value precision = 8;
for (int i = 0; i < cons_total; ++i)
mod_soft(code+mod_bits*i, cons[i], precision);
qpsk::soft(code+2*i, cons[i], precision);
}
CODE::PolarHelper<mesg_type>::PATH metric[mesg_type::SIZE];
shuffle(code);

8
encode.cc
View file

@ -29,7 +29,7 @@ struct Encoder
typedef float value;
typedef DSP::Complex<value> cmplx;
typedef int8_t code_type;
static const int mod_bits = 2;
typedef PhaseShiftKeying<4, cmplx, code_type> qpsk;
static const int code_order = 12;
static const int code_len = 1 << code_order;
static const int meta_len = 63;
@ -102,10 +102,6 @@ struct Encoder
fdom[first_subcarrier+1+i] = fdom[first_subcarrier+i] * cmplx(code[i] * nrz(seq()));
symbol();
}
cmplx mod_map(code_type *b)
{
return PhaseShiftKeying<4, cmplx, code_type>::map(b);
}
Encoder(DSP::WritePCM<value> *pcm, const uint8_t *inp) : pcm(pcm), crc(0x8F6E37A0)
{
leading_noise();
@ -123,7 +119,7 @@ struct Encoder
for (int j = 0; j < payload_symbols; ++j) {
for (int i = 0; i < subcarrier_count; ++i)
fdom[first_subcarrier+i] *=
mod_map(code+mod_bits*(subcarrier_count*j+i));
qpsk::map(code+2*(subcarrier_count*j+i));
symbol();
}
for (int i = 0; i < symbol_len; ++i)