Handling of Intra-UE Uplink Overlapping Grants for Heterogeneous Traffic in 5G Wireless Systems

Abstract: 5G system is considered as a wireless communication platform that could supporta variety of scenarios including industrial Internet of Things (IoT). Severalchallenges are to be addressed in order for 5G New Radio (NR) to enableindustrial automation, such as efficient multiplexing among heterogeneous industrialtraffic types. The heterogeneity of the industrial traffic is due to thesimultaneous existence of several critical and non-critical traffic types evenwithin a single UE, i.e., 1) Periodic deterministic, 2) Aperiodic deterministic,and 3) Non-deterministic. There have been several studies on achieving criticaltraffic requirements. However, this study focuses on maintaining QoS forcritical traffic while enhancing efficiency. The method chosen to achieve sucha target in this study is for gNB to send overlapping grants with different robustness.Furthermore, we focus on handling overlapping grants in the contextof the Intra-UE uplink scenario, from the media access control (MAC) layerperspective. The main advantage of our solutions is that it requires very lowcomplexity (comparing to other solutions, e.g., puncturing, spectrum sharing)resulting in minimal changes to existing standardization specifications. Usinga Java-based system-level simulator, our results show that the proposed solutioncould improve UE’s throughput by up to 25.9%, under specific simulationsettings, while maintaining latency requirements.