Abstract
A two-tier cellular network is characterized by macrocells and microcells overlapping in the service area. This overlapping property provides an advantage that traffic loads can be shared by channels of the two tiers to increase the performance of the system. In this paper, we propose two channel-sharing strategies, namely vertical channel-sharing and vertical-horizontal channel-sharing, to better utilize channels of the network. The call loss probability of new calls and call dropping probability of handoff calls are developed through analyses and simulations. The results justify the advantage of our strategies over existing strategies. © 2002 Elsevier Science B.V. All rights reserved.