本文介紹一種預先解碼的去尾迴旋碼之解碼器。此解碼器包括預先解碼器、儲存模組以及控制模組。預先解碼器，接收經過去尾迴旋碼編碼的序列數據對應的目前狀態、相鄰狀態與目前路徑狀態，產生已解碼位元，並根據目前狀態、相鄰狀態與目前路徑狀態、來判斷相鄰近階段之最小路徑計量的對應狀態之間是否有連貫性。儲存模組用以儲存已解碼位元。當相鄰近階段之最小路徑計量的對應狀態之間具有連貫性且已達到截斷長度時，控制模組選擇由儲存模組輸出已解碼位元、如果預先解碼流程失敗、便由原本傳統的方式解碼。

A pre-decoded tail-biting convolutional decoder and method are provided. The decoder includes a pre-decoder, a storage module and a control module. The pre-decoder receives the current state, the neighboring state and the current path corresponding to the sequence data encoded in tail-biting convolutional code (TBCC), generates predicted decoded bits, and determine whether the neighboring states corresponding to minimum branch metrics are continuous according to the current state, the neighboring state and the current path. The storage module stores the predicted decoded bits. The control module is connected to the pre-decoder and the storage module, and it outputs the predicted decoded bits from the
storage module when the neighboring states corresponding to minimum branch metrics are continuity.