Configured Grant for Ultra-Reliable and Low-Latency Communications: Standardization and Beyond

TL;DR

This paper reviews the standardization of configured grant mechanisms in 5G NR for ultra-reliable low-latency communication, highlighting recent advancements and challenges in supporting semi-deterministic traffic patterns.

Contribution

It details recent standardization efforts in Release 15 and 16 and proposes solutions to better support semi-deterministic traffic in configured grant allocations.

Findings

Standardized configured grant improves low-latency communication.

Challenges remain in supporting semi-deterministic traffic.

Recent advancements aim to enhance reliability and flexibility.

Abstract

Uplink configured Grant allocation has been introduced in 3rd Generation Partnership Project New Radio Release 15. This is beneficial in supporting Ultra-Reliable and Low Latency Communication for industrial communication, a key Fifth Generation mobile communication usage scenario. This scheduling mechanism enables a user with periodic traffic to transmits its data readily and bypasses the control signaling entailed to scheduling requests and scheduling grants and provides low latency access. To facilitate ultra-reliable communication, the scheduling mechanism can allow users to transmit consecutive redundant transmissions in a pre-defined period. However, if the traffic is semi-deterministic, the current standardized configured grant allocation is not equipped to emulate the traffic as the configured grant's period is pre-configured and fixed. This article describes the recent advancements in the standardization process in Release 15 and 16 for configured grant allocation and the prospective solutions to accommodate semi-deterministic traffic behavior for configured grant allocations.