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

Changsung Lee, Junsung Kim, Jaewook Jung, Jungsuk Baik, Jong Moon Chung

Research output: Contribution to journalArticlepeer-review


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.

Original languageEnglish
Pages (from-to)727-738
Number of pages12
JournalComputers, Materials and Continua
Issue number1
Publication statusPublished - 2022

Bibliographical note

Funding Information:
Funding Statement: This work was supported by the Institute of Information & communications Technology Planning & Evaluation (IITP) grant funded by the South Korea government (MSIT, 2021-0-00040, Development of intelligent stealth technology for information and communication resources for public affairs and missions).

Publisher Copyright:
© 2022 Tech Science Press. All rights reserved.

All Science Journal Classification (ASJC) codes

  • Biomaterials
  • Modelling and Simulation
  • Mechanics of Materials
  • Computer Science Applications
  • Electrical and Electronic Engineering


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