Performance of an overlapped macro-cell based location area scheme

In this paper, we define a new “location area” for location management in wireless networks. Location management schemes comprise of location update and terminal paging. Efforts to introduce efficient location update schemes results in increased paging costs and vice-versa. Dynamic Location Area (LA) schemes, which are per-user and mobility pattern based were proposed to overcome the problems of frequent location updates made by users in the LA boundary. In this work we propose a Base Station Controller (BSC) based scheme, which is a static scheme, but reduces the effect of frequent location updates at the boundary, by using the ‘overlap’ concept. The proposed LA, normally under the control of one BSC overlaps with adjacent LAs. We evaluate the scheme and compare it with other popular schemes like movementbased and distance-based LA schemes, which are more complex to implement. Though this type of BSCbased overlapped LA would result in minimal paging costs also, if the paging control were maintained at the BSC, the results of paging analysis have not been provided here due to space limitations. This scheme is simple to implement and has considerably reduced signalling traffic and associated costs. Another major contribution in this work is the extension of a mobility model, to study the location update rates in an ‘overlapped LA’ approach, which is difficult to analytically model.