EFFICIENT CONGESTION CONTROL TECHNIQUES FOR RANDOM ACCESS OF MTC DEVICES IN OFDMA SYSTEMS

摘要

This paper introduces how to support machine-to-machine (M2M) terminals that send a small data on 3rd generation partnership project (3GPP) long term evolution-advanced (LTE-A) system. Especially, we con-sider the lack of random access channel (RACH) and rapidly increasing average latency for both cellular users and countless M2M devices that also are known as machine type communications (MTC) devices. To resolve the overload on physical random access channel (PRACH), this paper studies how to group numerous MTC devices. We also propose a two-way design of efficient congestion control techniques with adaptive access probability and back-off index according to user-defined types. We can expect to improve the average latency by giving fair access opportunity to cellular users, although they have a disadvantage of access compared to MTC users. The simulations have been done under various assumptions for the validation of proposals. Our proposals can alleviate overload over PRACH as well as the average latency for cellular and M2M users through simulations.