High Throughput Polar Decoder for Long Code Length
Kaixiang Ruan, Jiaqi Huo, Mingxuan Jiang, Kai Niu, Chao Dong, Jincheng Dai · 2024
Successive cancellation list (SCL) algorithm designed for polar code is a serial structure.However, as the code length increases, it results in higher decoding latency and reduced throughput.To address this challenge, we developed the List Adjustment SCL (LA-SCL) algorithm.This approach is based on the observation that the polarization effect of polar code strengthens with longer length.Due to the encoding structure of polar codes, the larger bit-index subchannels the greater reliability compared to those in small bit-index.Based on this idea, we segment the input information, with each segment employing a successively reduced list size.Throughout this procedure, the hardware architecture remains constant.As the list size decreases with each segment, the hardware resources available for each surviving path effectively double for iterating LLR and the complexity of path sorting diminishes as the list size decreases, which significantly reduces the decoding latency and propels the decoder towards achieving a high throughput rate.