International Journal on Wireless Personal Communication manuscript No. (will be inserted by the editor) Call Admission and Hando Control in Multi-Tier Cellular Networks | Algorithms and Analysis

Abstract In this paper, we investigate a call-admission and hando-control framework for multi-tier cellular networks. We rst propose and compare Call-Admission Control (CAC) algorithms based on the cell-dwelling time, by studying their impact on the hando-call dropping and new-call blocking probabilities and the channel partitioning between the two tiers. Our results show that a simple, cell-dwelling-time-insensitive algorithm per-forms better under various mixes of user mobilities and call types. Moreover, there is an optimal channel partition of the overall spectrum between the tiers which minimizes the dropping and blocking probabilities for the two dierent CAC algorithms studied in this paper. Once the call is admitted into the network, we propose and compare various hando-queuing strate-gies to reduce the call dropping probability. We show that implementing a queuing framework in one of the tiers (especially the upper, i.e., macrocel-lular, tier), results in a signicant reduction in the dropping probability.