Modelling And Cost Analysis Of Location Management For Wireless Network

Location management is of importance in mobile communication network, which aims at effectively keeping track of user equipments (UEs) to ensure the netwotk rapidly and accurately delivers the call to the target UE and establishs a communication link when an incoming call arrives. The performance analysis plays an important role in the determining of the location management scheme and network system design, while the signaling cost analysis is a significant criterion in evaluating the location management scheme performance A lot of location management schemes are proposed to optimize and improve the performance of the location management schemes applied in the2G/3G/4G networks, including the movement-based location management scheme and the tracking area list (TAL)-based location management scheme applied in4G network.For the reason that the movement-based location management applied in2G/3G network fails to consider the HLR/VLR (Home Location Register/Visitor Location Register) architecture, this thesis considers the HLR/VLR, utilizes the Fluid Flow model, proposes an embedded Markov chain model, analyzes the location management cost under the condition that the time interval between two continuous incoming calls follows an exponential distribution and the cell residence time follows an arbitrary distribution. The closed-form formulas of the location update cost and the paging cost between two continuous incoming calls are derived in this thesis. Also, we get the optimal movement threshold to minimize the location management cost and analyze the influence of different parameters on the movement-based location management scheme.Because the TAL allocation scheme highly influences the performance of the TAL-based location management scheme in4G LTE network, while no optimal TAL allocation schemes to minimize the signaling cost of the TAL-based location management scheme are presented, this thesis devotes to looking for such an optimal TAL allocation scheme. Based on the fact that local UEs always stay in a relative small area and move in a strong pattern regularity, this thesis proposes an embedded Markov chain model to analyze the signaling cost of the TAL-based location management scheme for local UEs. We calculate the formulas of the tracking area update cost and the paging cost between two continuous incoming calls, derive an optimal TAL allocation scheme to minimize the signaling cost of the TAL-based location management scheme and analyze the influence of different parameters on the TAL-based location management scheme. Our thesis makes it possible to find an optimal movement threshold and an optimal TAL allocation scheme respectively to minimize the signaling cost of the movement-based location management scheme applied in2G/3G network and the TAL-based location management scheme applied in4G network. Moreover, the proposed embedded Markov chain model has a widely applicablity and the results we derive in this thesis may provide a theoretical basisfor the network architecture design.