Selective Reverse PAC Coding for Sphere Decoding

  title={Selective Reverse PAC Coding for Sphere Decoding},
  author={Xinyi Gu and Mohammad Rowshan and Jinhong Yuan},
—Convolutional precoding in polarization-adjusted convolutional (PAC) codes can reduce the number of minimum weight codewords (a.k.a error coefficient) of polar codes. This can result in improving the error correction performance of (near) maximum likelihood (ML) decoders such as sequential decoders and sphere decoders. However, PAC codes cannot be decoded by sphere decoding. The reason is twofold: 1) Sphere decoding of polar codes is performed from the last bit - due to the lower rectangular… 

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