Performance Of M2M Services And Random Access Control Optimization In Umts System

In recent years, M2M market demand is growing progressively, M2M services are becoming more and more prevalent, and they are turning into a group of applications with great developing potentials. At the same time, mobile operators in China are speeding up their process of network evolution, greatly promoting the third generation mobile networks among which UMTS is most widely used. And mobile networks will be a major way to carry M2M services, but its origin for human to human communication goes against the characteristic of M2M services, which results in a low efficiency in supporting M2M services. How to improve the existing mobile networks to make it more suitable for delivering M2M services has become the main focus of promoting M2M services.In this paper, we adopt different modeling and simulation mechanisms for time-driven and event-driven M2M services, simulate both small concurrent and large concurrent user number scenarios. For the small user number scenario, we commit research on services capacity of current mobile network, and for the large user number scenario, we do research on the optimization of random access procedure. Both the researches are verified by simulation, and expected results are achieved.In the first part, we build a platform for UMTS network simulation, and several custom M2M service models are added. We simulate the end to end delay, packet loss ratio, overall throughput and so on, as well as the impact to human to human communication introduced by M2M services. After analysis of a series of simulation results, we get the capacity of each service and mixed services in UMTS network. We also conclude that with the introduction of M2M services, human to human communication is obviously influenced, such as higher access delays and lower probability of successful sessions.In the second part, common access control protocols, random access conflicting solutions and random access procedure in UMTS are summarized. Several existing access control schemes for bursting M2M services are analyzed, their advantages and disadvantages are listed, and reasons for their disadvantages are given. An optimized access control scheme is proposed to conquer the existing problems, correctness of the scheme is verified through simulation.