Abstract
A two-tier cellular network is characterized by overlapping of macrocells and microcells in the service area. This overlapping property provides an advantage that traffic loads can be shared by the two tiers to increase the performance of the system. In this paper, we propose two channel-sharing strategies, namely vertical loadsharing and horizontal load-sharing, to better utilize channels of the network. The call loss probability of new calls and call dropping probability of handoffs are developed through analysis and simulation. The results justify the advantage of our strategies over existing strategies.