5G Evolution: A View on Cellular Technology Beyond 3GPP Rel 15

The 5G System is being developed and enhanced to provide unparallel connectivity to connect Everyone and Everything. The 5G System based on Rel 15, comprising 5G Core and 5G New Radio (NR) with 5G User Equipment, is currently being commercially deployed throughout the world both at sub 6 GHz and at mmWave frequency bands. Concurrently, the second phase of 5G is being standardized in 3GPP and Rel 16 version of the specifications will be completed by March-2020. While the main focus of Rel 15 was on enhanced mobile broadband services, the focus of Rel 16 is on new features for URLLC (Ultra Reliable Low Latency Communication) and Industrial IoT, including Time Sensitive Communication, enhanced Location Services, and support for Non-Public Networks. Furthermore, some crucial features such as NR on unlicensed bands (NR-U), Integrated Access & Backhaul, NR Vehicular-to-X (V2X) and enhancements for massive MIMO support, wireline wireless convergence, enhancements to Service Based Architecture (SBA) and Network Slicing are also introduced as part of Rel 16. Finally, the number of use cases, connectivity and user types as well as applications running on top of 5G networks are expected to increase dramatically. As a consequence, 5G devices and networks will face higher number and scale of threats (new and varied attack types) thus the standards should ensure that these attacks can be mitigated. In this paper, we discuss the Rel 16 features and provide an outlook towards 3GPP Rel 17, with emphasis on new features and continued enhancements of existing features while maintaining backward compatibility. We believe that 5G Evolution should focus on three pillars: a) features that are needed for operational enhancements, b) enhancements to features introduced in Rel 15 and Rel 16, and c) new Rel 17 features to further expand the applicability of the 5G System to other markets and use cases. To that end, the key features considered in this paper include, Industrial IoT related features, 5G NR at high mmWave frequencies, Non-Terrestrial Networks, further MIMO enhancements, NR-Unlicensed and Sidelink communication for applications like V2X and 5G security is essential part of the technology evolution.