Dynamic Location Update Scheme Research Articles

Adaptive location update area design for wireless cellular networks under 2D Markov walk model

In wireless cellular networks, location management operation expends the limited wireless resources to keep track the location information of a mobile terminal. Various dynamic location update (LU) schemes have been proposed to improve the efficiency of location management. However, most of them only work for certain mobility patterns. In this paper, we propose a new scheme that the LU area is adaptively designed according to the mobility pattern and traffic parameters. The 2D Markov walk is used as the mobility model which describes a broad class of mobility patterns. A recursive algorithm is developed to compute the location management cost of a general LU area shape. Due to the high computational complexity of the adaptive LU area design problem, we use an iterative greedy heuristic algorithm to find an approximation solution of the problem efficiently. The effects of the mobility patterns and traffic parameters on the designed LU area shape are investigated. Experimental results show that the LU area designed by the heuristic algorithm can adaptively change according to the given mobility pattern and traffic parameters. Compared with some existing dynamic LU schemes, the proposed adaptive LU scheme is more flexible and efficient for location management.

Optimal Sequential Paging in Cellular Wireless Networks

In a high-capacity cellular network with limited spectral resources, it is desirable to minimize the radio bandwidth costs associated with paging when locating mobile users. Sequential paging, in which cells in the coverage area are partitioned into groups and paged in a non-increasing order of user location probabilities, permits a reduction in the average radio costs of paging at the expense of greater delay in locating the users. We present a polynomial time algorithm for minimizing paging cost under the average delay constraint, a problem that has previously been considered intractable. We show the conditions under which cluster paging, a simple heuristic technique proposed for use with dynamic location update schemes, is optimal. We also present analytical results on the average delay and paging cost obtained with sequential paging, including tight bounds.