A Location Management Scheme Using Direction Characteristics of Mobile Terminals in Mobile Communication Networks

Abstract

Recently, as the number of mobile terminals (or users) keeps explosively increasing, the location management to track the mobile terminals in mobile communication networks is becoming more important. However, previous schemes have used static location information without any consideration about the moving direction of a mobile terminal. For a fixed paging area, this results in unnecessary pagings, thus increasing the location management cost. In this paper, we propose a new location management scheme using the direction characteristics of a mobile terminal. The direction vector is defined to represent the moving direction of a mobile terminal and to compute a distance from the cell where a location update occurs to the current cell. The offset operation of direction vectors is also presented to represent the position of a mobile terminal in a paging area. This allows the mobile terminal to determine whether a location update will be performed or not. The mobile terminal can also vary its own paging area dynamically according to its moving direction whenever it moves across its paging area. In addition, we develop an analytical model for the proposed scheme which captures the direction characteristics of a mobile terminal based on the Markov model. Analytical results show that the proposed scheme can reduce location management cost by forming a dynamic paging area along the moving direction of a mobile terminal when compared to other schemes.