Random Access Process Enhancements for Cellular Internet of Things (CIoT)

Abstract

Random Access (RA) is an important process in Cellular Internet of Things (CIoT), which enables the IoT devices to connect to the network for set-up and data transmission. As the number of IoT devices in the network is increasing, the competition for accessing the network increases as well. Additionally, since each IoT application may have different requirements in terms of parameters such as data size, latency, and data rate, it is essential to optimize the random access process to address the requirements of different applications. Therefore, there is a need to design the uplink transmission mechanism to reduce the signaling overhead being exchanged between the User Equipment (UE) and the base station. The 3rd Generation Partnership Project (3GPP) has introduced several random access process enhancements in Release 13 through 16, for IoT devices that have small data size or the ones that not only send small amount of data, but also have a deterministic traffic or a predicated traffic pattern. In this paper, we first discuss the random access process and its advancements and then, explain the applicability of the existing features for some practical IoT use cases. The results of this study shows that RA process developed in release 15 and 16 under certain conditions can increase the efficiency of IoT applications by reducing the latency and power consumption.