Highly Mobile Users and Paging: optimal polling strategies

Previous work considered the problem of minimizing paging cost subject to delay constraints. However, it was assumed that the unit to be found did not move during the paging process. This paper extends the work to the case where the unit may change location during polling events. We show that the optimum polling strategies search the conditionally most probable locations given that the unit has not yet been found. We find the optimal sequential paging strategies for given maximum delay constraints and compute both paging and delay costs as a function of the time between polling events. 1 INTRODUCTION Previous work [1, 2] has considered the problem of minimizing the average cost of locating a mobile unit given the probability distribution on unit location. The cost was formulated in terms of delay and number of locations searched. However, units were assumed to move slowly relative to the total duration of the paging process; i.e., it was assumed the unit did not change location duri..