Research Article
Improved Incremental Freezing HARQ Schemes Using Polar Codes over Degraded Compound Channels
@INPROCEEDINGS{10.1007/978-3-030-41114-5_24, author={Tianze Hu and Lei Xie and Huifang Chen and Hongda Duan and Kuang Wang}, title={Improved Incremental Freezing HARQ Schemes Using Polar Codes over Degraded Compound Channels}, proceedings={Communications and Networking. 14th EAI International Conference, ChinaCom 2019, Shanghai, China, November 29 -- December 1, 2019, Proceedings, Part I}, proceedings_a={CHINACOM}, year={2020}, month={2}, keywords={Degraded compound channel Polar codes Incremental freezing HARQ scheme Path splitting reduced SCL decoding algorithm}, doi={10.1007/978-3-030-41114-5_24} }- Tianze Hu
Lei Xie
Huifang Chen
Hongda Duan
Kuang Wang
Year: 2020
Improved Incremental Freezing HARQ Schemes Using Polar Codes over Degraded Compound Channels
CHINACOM
Springer
DOI: 10.1007/978-3-030-41114-5_24
Abstract
The error propagation problem in incremental freezing (IF) hybrid automatic repeat request (HARQ) scheme using Polar codes is studied. We propose two IF HARQ schemes using polar codes, namely the cyclic redundancy check (CRC)-aided IF HARQ scheme and the cumulative-path-metrics-based IF HARQ scheme. In the CRC-aided IF HARQ scheme, several CRC bits are added to each transmitted block. Using these CRC bits, the proposed IF HARQ scheme and the Chase Combining HARQ scheme can be combined to achieve a better error correction performance in the cost of a larger decoding delay. In the cumulative-path-metrics-based IF HARQ scheme, the successive joint decoder maintains multiple possible paths simultaneously, and the cumulative path metrics is used to represent the reliability of each surviving path in the decoding process. Moreover, a modified path splitting reduced successive cancellation list (SCL) decoding algorithm is presented to reduce the computational complexity and the memory requirement of cumulative-path-metrics-based IF HARQ scheme. Simulation results show that, using the Polar code constructed under long block length and high block error rate, the CRC-aided IF HARQ scheme has a higher system throughput. With the Polar code constructed under short block length and low block error rate, the cumulative-path-metrics-based IF HARQ scheme has a higher system throughput. In both situations, the system block error rate of the CRC-aided IF HARQ scheme performs well.
