std::vector<double> LDPCDecoder::deModLlr(std::vector<double> phase,
std::vector<double> quad, double n0) {
if (quad.size() != phase.size()) {
throw std::invalid_argument("Invalid input size");
}
std::vector<double> llrs;
int modSize = log2(symbols);
//LLR calculation
for (int s = 0; s < phase.size(); s++) {
//LLR for the symbol
std::vector<double> llr_symbol = llr(phase.at(s), quad.at(s), n0);
for (int j = 0; j < modSize; j++) {
llrs.push_back(llr_symbol.at(j));
}
}
llrs = deInterleave(llrs);
return llrs;
}
struct BPTC1969 decodeBPTC1969(bool bits[264]){
bool *infoBits; //196 info bits
bool *deInterleavedBits; //196 bits
static bool *payloadBits; //96 bits
int blocksToFollow=0,a;
unsigned char dpf=0,sap=0,bitPadding=0;
struct BPTC1969 BPTC1969decode;
infoBits = extractInfo(bits);
deInterleavedBits = deInterleave(infoBits);
payloadBits = extractPayload(deInterleavedBits);
/*printf("Payload bits\n");
for(a=0;a<96;a++){
printf("%i",*(payloadBits+a));
}
printf("\n");*/
if(*(payloadBits+1) == 1){
BPTC1969decode.responseRequested = true;
//syslog(LOG_NOTICE,"response requested");
}
else{
BPTC1969decode.responseRequested = false;
//syslog(LOG_NOTICE,"NO response requested");
}
for(a=4;a<8;a++){
if(*(payloadBits + a) == true) dpf = dpf + (char)(8 / pow(2,a-4));
}
//syslog(LOG_NOTICE,"Data Packet Format: ");
BPTC1969decode.dataPacketFormat = dpf;
switch (dpf){
case 0:
//syslog(LOG_NOTICE,"Unified Data Transport\n");
break;
case 1:
//syslog(LOG_NOTICE,"Response packet\n");
break;
case 2:
//syslog(LOG_NOTICE,"Data packet with unconfirmed delivery\n");
break;
case 3:
//syslog(LOG_NOTICE,"Data packet with confirmed delivery\n");
break;
case 13:
//syslog(LOG_NOTICE,"Short Data: Defined\n");
break;
case 14:
//syslog(LOG_NOTICE,"Short Data: Raw or Status/Precoded\n");
break;
case 15:
//syslog(LOG_NOTICE,"Proprietary Data Packet\n");
break;
}
for(a=8;a<12;a++){
if(*(payloadBits + a) == true) sap = sap + (char)(8 / pow(2,a-8));
}
//syslog(LOG_NOTICE,"SAP id: ");
BPTC1969decode.sapId = sap;
switch (sap){
case 0:
//syslog(LOG_NOTICE,"Unified Data Transport\n");
break;
case 2:
//syslog(LOG_NOTICE,"TCP/IP header compression\n");
break;
case 3:
//syslog(LOG_NOTICE,"UDP/IP header compression\n");
break;
case 4:
//syslog(LOG_NOTICE,"IP based Packet data\n");
break;
case 5:
//syslog(LOG_NOTICE,"Address Resolution Protocol(ARP)\n");
break;
case 9:
//syslog(LOG_NOTICE,"Proprietary Packet data\n");
break;
case 10:
//syslog(LOG_NOTICE,"Short Data\n");
break;
}
if (dpf == 13){
for(a=12;a<16;a++){//only AB in 2nd octet
if(*(payloadBits + a) == true) blocksToFollow = blocksToFollow + (char)(8 / pow(2,a-12));
}
BPTC1969decode.appendBlocks = blocksToFollow;
//syslog(LOG_NOTICE,"Appended blocks : %i\n",blocksToFollow);
for(a=72;a<80;a++){
if(*(payloadBits + a) == true) bitPadding = bitPadding + (char)(128 / pow(2,a-12));
}
}
return BPTC1969decode;
}
