OPTIMIZATION OF WIRELESS RESOURCES FOR PERSONAL COMMUNICATIONS MOBILITY TRACKING

In personal communications applications, users communicate via wireles s with it wireline network. The wireline network tracks the current lo cation of the user, and can therefore route messages to a user regardl ess of the user's location, In addition to its impact on signaling wit hin the wireline network, mobility tracking requires the expenditure o f wireless resources as well, including the power consumption of the p ortable units carried by the users and the radio bandwidth used for re gistration and paging, Ideally, the mobility tracking scheme used for each user should depend on the user's call and mobility pattern, so th e standard approach, in which all cells in a registration area are pag ed when a cap arrives, may be wasteful of wireless resources, In order to conserve these resources, the network must have the capability to page selectively within a registration area, and the user must announc e his or her location more frequently, In this paper, we propose and a nalyze a simple model that captures this additional flexibility. Dynam ic programming is used to determine an optimal announcing strategy for each user, Numerical results for a simple one-dimensional mobility mo del show that the optimal scheme may provide significant savings when compared to the standard approach even when the latter is optimized by suitably choosing the registration area size on a per-user basis, Ong oing research includes computing numerical results for more complicate d mobility models and determining how existing system designs might be modified to incorporate our approach.