A Node-Reliability Based CRC-Aided Successive Cancellation List Polar Decoder Architecture Combined With Post-Processing

Abstract

This paper presents a node-reliability based cyclic redundancy check (CRC)-aided successive cancellation list (NRB CA-SCL) polar decoder architecture, where node reliability is used to determine the number of expanding paths, and a priority-based sorter is devised so as to reduce the number of sorting cycles. In order to reduce the effort required for sorting by the node processor, the expanding segments are generated using off-line flipping patterns. We also propose a post-processing scheme that improves the error-rate performance for the NRB CA-SCL decoders. The proposed techniques are demonstrated by implementing (1024, 512) polar decoders. Compared to other state-of-the-art CA-SCL decoders, the proposed decoder, when the post-processing technique is not included, achieves a better area efficiency. When the post-processing technique is included, the proposed list-16 decoder achieves an area efficiency that is almost 2.5 times greater compared to the latest list-32 CA-SCL decoder, as well as a similar error-rate performance.