在本論文中，我們提出了兩個新版本的非二位元低密度偶校碼之平行符元翻轉解碼法。模擬結果顯示，軟判決平行符元翻轉解碼法的效能優於許多現有基於可靠性消息傳遞的解碼法。與q 元和積演算法相比，它提供了一個有效的錯誤效能和解碼的複雜性之間的權衡。在系統需要一個簡單的解碼器或者軟信息無法取得的情況下，該算法可以簡化為硬判決平行符元翻轉解碼法。當非二位元低密度偶校碼的偶校驗矩陣有大的行和列比重時，這兩個解碼法效能特別好。

Two versions of a new parallel symbol-flipping decoding algorithm for non-binary low-density parity-check (NB-LDPC) codes are proposed. Simulation results show that the soft-decision parallel symbol-flipping decoding outperforms quite a number of existing reliability-based message-passing algorithms. It provides an effective trade-off between error performance anddecoding complexity compared with the q-ary sum-product algorithm. The algorithm can be simplified to hard-decision parallel symbol-flipping decoding for applications in communication or storage systems where either soft information is not available or a simple decoder is needed. They are particularly effective for decoding NB-LDPC codes whose parity-check matrices have large row/column weights.

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