Dynamic Preamble Grouping and Access Control Scheme in Machine-to-Machine Communication

Abstract

In the Internet of Things (Io'T), machine-to-machine (M2M) communication involves a significant number of machine type communication (MTC) devices to support the application of various sensors. With the rapid development of IoT technology, the number of MTC devices has increased dramatically. Random access of devices may lead to packet loss, congestion conflicts, and even make the information to be useless. Therefore, it is crucial to overcome the overload problem caused by random access requests from large-scale MTC devices. This paper presents a preamble grouping scheme and dynamic access class barring (ACB) scheme based on estimating the number of devices. Firstly, the number of devices is estimated according to the preambles in the collision. Secondly, MTC devices are divided into two sets according to the delay-sensitive characteristics. At the same time, the preamble resources are dynamically allocated to each type of M2M service. Finally, the ACB factor is adjusted according to the number of devices. The proposed scheme can improve the successful access performance of M2M network and meet the delay requirements of delay-sensitive devices. To solve the performance degradation caused by large-scale random access when delay sensitivity and delay-tolerant requests coexist. The analysis and simulation prove the validity of the design.