ORBGRAND Is Almost Capacity-Achieving

Decoding via sequentially guessing the error pattern in a received noisy sequence has attention recently, and ORBGRAND been proposed as one such decoding algorithm that is capable of utilizing soft information embedded sequence. An theoretic study conducted for ORBGRAND, it shown achievable rate using independent identically distributed random codebooks almost coincides with channel capacity, an additive white Gaussian noise under antipodal input. For finite-length codes, improved schemes motivated by are attain lower rates than especially high signal-to-noise ratio regime.