Delay Based Handover Algorithm Design for Femtocell Networks

Abstract

Mobile communications systems have limited frequency resources to operate with. In traditional macrocell architectures, this problem is addressed by utilizing smaller cells to employ frequency reuse among cells. A new promising solution is to use two-tier networks that employs smaller cells called femtocells which are plug-and-play devices that use the broadband internet connection to connect to the operator’s core network. However, successful deployment of femtocells requires modifications on the existing network structures. An important adjustment is required on the handoff protocols to provide quality of service requirements that the users need. The traditional network approaches that does not consider the broadband internet backhaul for quality of service is inadequate in two-tier networks. This is due to the fact that users connect to operators core network via broadband internet connection. In this paper we focus on the handover/handoff problem in two-tier networks and propose a novel handoff/handover algorithm that considers both wired and wireless medium requirements for service quality. The performance of the proposed algorithm is evaluated using the handover rate and signal degradation rate as key indicators. The simulation studies demonstrate that better results are achieved with the proposed algorithms compared to existing ones in the literature.