5G System Design

13Initial Access, RRC and Mobility

Mårten Ericson¹, Panagiotis Spapis², Mikko Säily³, Klaus Pedersen⁴, Yinan Qi⁵, Nicolas Barati⁶, Tommy Svensson⁷, Mehrdad Shariat⁸, Marco Giordani⁹, Marco Mezzavilla¹⁰, Mark Doll¹¹, Honglei Miao¹² and Chan Zhou²

¹ Ericsson Research, Sweden

² Huawei German Research Center, Germany

³ Nokia Bell Labs, Finland

⁴ Nokia Bell Labs, Denmark

⁵ Samsung Electronics R&D Institute, UK

⁶ New York University, USA

⁷ Chalmers University of Technology, Sweden

⁸ Samsung Electronics R&D Institute, UK

⁹ University of Padova, Italy

¹⁰ New York University, USA

¹¹ Nokia Bell Labs, Germany

¹² Intel, Germany

With contributions from Hao Guo, Nima Jamaly, Behrooz Makki, Mikael Sternad and Anna Wigren.

13.1 Introduction

This chapter covers the control plane (CP) procedures for the access of a user equipment (UE) to the network. In general, the system access is a rather complex procedure, and depending on the used mechanisms and the requirements it may be an inefficient process resulting in waste of resources. The 5^th generation (5G) CP functions for the system access have the same purpose as in older generations of mobile systems, such as Wideband Code Division Multiple Access (WCDMA) and Global System for Mobile Communications (GSM). However, new requirements in 5G, for instance related to latency and energy efficiency, raise the need for different and more efficient approaches.

To easier understand the role of the CP functions, consider the events in Figure 13‐1, which depicts a UE's life ...