Research On Improving Signaling Load In LTE System

With the rapid development of mobile Internet, the development of mobile applications trends to be more and more diversified, meanwhile, the mobile data traffic ushers in a period of prosperity and development. However, widespread smart devices and the diversified mobile data traffic put a lot of pressure on the current mobile cellular network. The features of the mobile data traffic can be summarized as follow: frequently access to the network, always online and frequent transmission of small packets. These features will consume a large number of signaling resources, which are used to controll the network to work properly, resulting in the overload of network signaling and network congestion. It is also known as the signaling storm.As a mainstream technology of the future mobile communication system, LTE has been well developed and wide spread. However, since LTE system was not specified designed to slove the signaling storm problem, signaling overload will also happen in LTE system. It is necessary to propose some schemes to slove the signaling storm problem before LTE system is widely commercial used.In the background, this paper launched the research of optimization on signaling load in the LTE system, including:First of all, from the point of LTE protocol we study the signaling storm problem in LTE system and point out that frequent RRC state transition, which caused by the mobile data traffic, is the main cause of signaling overload. By reading some releated literatures, this paper summarizes and analysis some existing schemes used to optimize the signaling load of LTE system. Then, this paper also summarizes the features of mobile data traffic.Second, according to the existing method which is based on Poisson distribution and the Markov model, this paper extends this method and then proposes an improved model. With the improved model we make a quantitative analysis of the power consumption of UE and the signaling load of the network. Then, under the power consumption constraint condition, this paper discusses the method to improve the signaling load of the network.Last, since it always has several applications running on the smart device, the mobile data traffic of such smart device is complicated and unable to predict. So this paper proposes a modeling method to simulate the mobile data traffic under the scene that multi services running on a smart device. Meanwhile, to improve the signaling load of the network under this scene, this paper proposes an optimization mechanism, named A Dynamic Adjustment Mechanism of RRC Connection Release Timer. Finally, we simulate to verify the validity of the optimization mechanism and prove that it can keep the signaling load of the network from exceeding the alarm value.