Optimal Pipeline Paging Load Balancing for Hierarchical Cellular Networks

We study load balancing of paging schemes for multitier hierarchical cellular networks, in which different tiers of cells overlay each other to provide multiple coverage in cellular service areas. Each mobile terminal (MT) can be paged in any tier of a multitier hierarchical cellular network. Paging requests are balanced in different waiting queues of different tiers, and the load balancing among them is achieved probabilistically among N tiers. The studied paging schemes are the Hierarchical Pipeline Paging scheme, the Hierarchical Sequential Paging scheme, and the Hierarchical Blanket Paging scheme. We study two optimization problems using the N-tier load balancing: 1) given a paging delay constraint, to minimize the total paging cost under the constraint that the total delay is upper bounded by a predefined total delay, and 2) given a bound on the total delay, to minimize the total paging cost under a paging delay constraint.