基于移动的位置管理策略中最优寻呼研究  

Research on Optimal Paging in Movement-Based Location Management Scheme

作　　者：朱艺华[1] 朱帆[2] 罗和治[3] 

机构地区：[1]浙江工业大学信息工程学院,杭州310032 [2]浙江工业大学国际学院计算机系,杭州310032 [3]浙江工业大学理学院数学系,杭州310032

出　　处：《计算机研究与发展》2007年第7期1199-1204,共6页Journal of Computer Research and Development

基　　金：国家自然科学基金项目(60473097;60673177);浙江省自然科学基金重点项目(Z105185);教育部留学回国人员基金项目

摘　　要：位置管理是个人通信网络的一个挑战性问题,用于跟踪移动台,有位置更新与寻呼两个基本操作.在一些知名的位置管理策略中,基于移动的位置管理策略(movement-based location management scheme)具有简单易行的特点:各移动台只需记住所越过的小区边界次数,一旦这个数超过事先定义的一个整数---移动门槛,就进行位置更新操作.在移动台的呼入符合泊松分布,移动台在各个小区的逗留时间符合指数分布的条件下,推导了基于移动的位置管理策略中移动台移动距离的概率分布及平均距离公式,并基于这些概率分布给出了最优顺序寻呼算法.最后,给出数值分析结果,以说明所给出的寻呼策略比其他已有策略更优.Location management （LM）, which is a challenging problem in personal communication service （PCS） networks, is used to track mobile terminals （MTs） . Basically, it consists of two operations： location update and paging. Location update is a process in which the MT informs the network of its current location, while paging is a process in which the network searches for a called MT. There are three dynamic LM schemes, namely, time-based, distance-based, and movement-based LM schemes. The mov, ement-based is simple to implement, in which each MT simply counts the number of cell boundary crossings and initiates location update when this number exceeds the predefined movement threshold. In the LM scheme used in the existing PCS networks such as GSM, a blanket paging is used that all the cells in a location area （LA） are simultaneously paged. This paging scheme consumes extra resources since the MT only stays in one cell of the paged LA consisting of a group of cells. Therefore, sequential paging schemes are proposed to overcome the drawback. In this paper, emphasis is put on optimal sequential paging for movement-based LM scheme. Both the probability distribution of an MT＇s moving distance and expected moving distance in a movement-based scheme are derived on the condition that the incoming calls form a Poisson process and the MT＇s cell residence time has exponential probability distribution. Besides, based on the derived statistics, an optimal sequential paging algorithm is proposed. Finally, numeric results show that it outperforms some well-known sequential paging schemes.

关 键 词：移动性管理 位置管理 顺序寻呼 个人通信网络 最优化 

分 类 号：TN929.5[电子电信—通信与信息系统] TP393[电子电信—信息与通信工程]