LAUSR

This letter focuses on the path metric sorting of successive cancellation list (SCL) decoder for polar codes. The metric sorter is a major challenge of SCL decoder in terms of overall latency. We propose a hybrid bucket sorting method to select $L$ unordered paths with the smallest metrics out of the $2L$ paths. Each hybrid bucket sorter (HBS) consists of an optimized bucket sorter and a half cleaner. Evaluation results indicate that the HBS outperforms state-of-the-art metric sorters in terms of latency reduction.