Adaptive design of tracking area list in LTE

In Long Term Evolution (LTE), service area is divided into tracking areas (TAs), which consist of a group of cells and do not overlap with each other, and a TA list (TAL) is assigned to a mobile station (MS). Thus, location of an MS is managed by a granularity of a TAL and an MS does not need to register its location when it moves within TAs of the assigned TAL. In this paper, it is assumed that each TA consists of only one cell and TAL is formed by a group of cells. As a preliminary work to the optimal design of TAL for an individual MS, we validate the usefulness of the proposition that a TA consists of only one cell and TAL can be adaptively designed for each MS, by assuming uniform mobility model of MSs to simplify the analysis. TAL for an MS is designed as rings of cells (TAs) from the last update cell (TA), as an example of optimal design of TAL, by applying the concept of movement-based location registration. An optimal movement threshold for the TAL is derived periodically, using measured traffic and mobility characteristics of an MS during the time interval between two consecutive session arrivals. Finally, a new TAL is adaptively designed for an MS, based on the newly derived optimal movement threshold.