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LoRa demod: implement LoRa

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f4exb
2020-02-19 09:26:42 +01:00
parent c6f8ac2ca4
commit be2ca2d0fd
21 changed files with 1592 additions and 243 deletions
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plugins/channeltx/modlora/loramodencoderlora.cpp
+5 -5
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@@ -40,7 +40,7 @@ void LoRaModEncoderLoRa::encodeBytes(
}
unsigned int payloadSize = bytes.size();
const unsigned int numCodewords = roundUp(bytes.size()*2 + (hasHeader ? 5 : 0), nbSymbolBits);
const unsigned int numCodewords = roundUp(bytes.size()*2 + (hasHeader ? headerCodewords : 0), nbSymbolBits);
unsigned int cOfs = 0;
unsigned int dOfs = 0;
@@ -65,7 +65,7 @@ void LoRaModEncoderLoRa::encodeBytes(
// fill nbSymbolBits codewords with 8 bit codewords using payload data (ecode and whiten)
encodeFec(codewords, 4, cOfs, dOfs, reinterpret_cast<const uint8_t*>(bytes.data()), nbSymbolBits - headerSize);
Sx1272ComputeWhitening(codewords.data() + headerSize, nbSymbolBits - headerSize, 0, 4);
Sx1272ComputeWhitening(codewords.data() + headerSize, nbSymbolBits - headerSize, 0, headerParityBits);
// encode and whiten the rest of the payload with 4 + nbParityBits bits codewords
if (numCodewords > nbSymbolBits)
@@ -75,15 +75,15 @@ void LoRaModEncoderLoRa::encodeBytes(
Sx1272ComputeWhitening(codewords.data() + cOfs2, numCodewords - nbSymbolBits, nbSymbolBits - headerSize, nbParityBits);
}
const unsigned int numSymbols = 8 + (numCodewords / nbSymbolBits - 1) * (4 + nbParityBits); // header is always coded with 8 bits
const unsigned int numSymbols = headerSymbols + (numCodewords / nbSymbolBits - 1) * (4 + nbParityBits); // header is always coded with 8 bits
// interleave the codewords into symbols
symbols.clear();
symbols.resize(numSymbols);
diagonalInterleaveSx(codewords.data(), nbSymbolBits, symbols.data(), nbSymbolBits, 4);
diagonalInterleaveSx(codewords.data(), nbSymbolBits, symbols.data(), nbSymbolBits, headerParityBits);
if (numCodewords > nbSymbolBits) {
diagonalInterleaveSx(codewords.data() + nbSymbolBits, numCodewords - nbSymbolBits, symbols.data() + 8, nbSymbolBits, nbParityBits);
diagonalInterleaveSx(codewords.data() + nbSymbolBits, numCodewords - nbSymbolBits, symbols.data() + headerSymbols, nbSymbolBits, nbParityBits);
}
// gray decode