Open Access

ARTICLE

HARQ Optimization for PDCP Duplication-Based 5G URLLC Dual Connectivity

by Changsung Lee^1,3, Junsung Kim^2,3, Jaewook Jung³, Jungsuk Baik³, Jong-Moon Chung^3,*

1 Samsung Research, Seoul, 06765, Korea
2 Samsung Electronics, Suwon, 16677, Korea
3 School of Electrical and Electronic Engineering, Yonsei University, Seoul, 03722, Korea

* Corresponding Author: Jong-Moon Chung. Email:

Computers, Materials & Continua 2022, 72(1), 727-738. https://doi.org/10.32604/cmc.2022.024824

Received 01 November 2021; Accepted 07 December 2021; Issue published 24 February 2022

Abstract

Packet duplication (PD) with dual connectivity (DC) was newly introduced in the 5G New Radio (NR) specifications to meet the stringent ultra reliable low latency communication (URLLC) requirements. PD technology uses duplicated packets in the packet data convergence protocol (PDCP) layer that are transmitted via two different access nodes (ANs) to the user equipment (UE) in order to enhance the reliability performance. However, PD can result in unnecessary retransmissions in the lower layers since the hybrid automatic retransmission request (HARQ) operation is unaware of the transmission success achieved through the alternate DC link to the UE. To overcome this issue, in this paper, a novel duplication-aware retransmission optimization (DRO) scheme is proposed to reduce the resource usage induced by unnecessary HARQ retransmissions. The proposed DRO scheme can minimize the average channel use while satisfying the URLLC requirements. The proposed DRO scheme derives the optimal HARQ retransmission attempts for different ANs by solving a nonlinear integer programming (NLIP) problem. The performance of the proposed DRO scheme was evaluated using MATLAB simulation and is compared to the existing 5G HARQ support schemes. The simulations results show that the proposed DRO scheme can provide a 14.71% and 15.11% reduced average channel use gain compared to the selective data duplication upon failure (SDUF) scheme and latency-aware dynamic multi-connectivity algorithm (LADMA) scheme, respectively, which are the existing 5G PD schemes that use HARQ.

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Keywords

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