Esa Tiirola, and Preben Mogensen, "Achieving low latency and energy consumption by 5G TDD mode optimization," ICC'14 Workshop on 5G Technolo- gies. Sydney, Australia 2014. 30 S.G. Larew, T.A. Thomas, M. Cudak, and A. Ghosh, "Air interface design and ray tracing study for 5G millimeter wave communications," 2013 IEEE Globecom Work- shops (GC Wkshps), pp. 117, 122, 9-13, 2013. 5G RF Design Challenges Petri Vasenkari1, Dominique Brunel ², and Laurent Noël³ 1 Nokia Bell Labs, Finland 2 Skyworks, France 3 Skyworks, Canada CHAPTER MENU Introduction, 349 Impact of New Physical Layer on RF Performance, 350 5G Standalone Performance Aspects in Frequency Range 1, 363 5G Standalone Performance Aspects in mmWave Frequency Range 2, 373 Dual Uplink Performance Challenges for NSA Operation, 381 Examples of UE Implementation Challenges, 392 Summary, 396 References, 397 12.1 Introduction 5G brings changes compared to Long-Term Evolution (LTE) for the user equipment (UE) radio frequency (RF) design aspects in many ways. There is larger bandwidth with higher bandwidth occupancy, and there is dual connectivity with two uplink (UL) transmissions as baseline feature as well as operation with higher frequency bands than LTE could achieve. This chapter covers the impacts on the UE RF design from both standalone 5G as well as from the dual connectivity perspective, considering the large number of frequency bands that must be supported. Also, the impacts originating from mmW support, including the need for Over the Air Testing (OTA), is covered. This chapter concludes with an analysis of the multi-band as well as mmW UE implementation issues, including mmW UE antenna placement considerations. 5G Technology: 3GPP New Radio, First Edition. Edited by Harri Holma, Antti Toskala, and Takehiro Nakamura. © 2020 John Wiley & Sons Ltd. Published 2020 by John Wiley & Sons Ltd. 12 5G RF Design Challenges 12.2 Impact of New Physical Layer on RF Performance 12.2.1 New Uplink Waveforms In 5G New Radio (NR), a number of innovations have targeted improve