Achieving Ultra-Reliable Low-Latency Communications: Challenges and Envisioned System Enhancements

TLDR

URLLC can enable new applications such as industrial automation and autonomous vehicles, but 5G faces challenges in downlink reliability, link adaptation, retransmission latency, and multiplexing with other services. The article aims to address these challenges by proposing state‑of‑the‑art solutions for the radio interface. It proposes state‑of‑the‑art solutions for various radio‑interface aspects. Simulation results demonstrate that the proposed techniques can work together to meet the stringent latency and reliability targets of future URLLC applications.

Abstract

URLLC have the potential to enable a new range of applications and services: from wireless control and automation in industrial environments to self-driving vehicles. 5G wireless systems are faced by different challenges for supporting URLLC. Some of the challenges, particularly in the downlink direction, are related to the reliability requirements for both data and control channels, the need for accurate and flexible link adaptation, reducing the processing time of data retransmissions, and the multiplexing of URLLC with other services. This article considers these challenges and proposes state-of-the-art solutions covering different aspects of the radio interface. In addition, system-level simulation results are presented, showing how the proposed techniques can work in harmony in order to fulfill the ambitious latency and reliability requirements of upcoming URLLC applications.