Mitigation of Redundant Handovers to Femtocells by Estimation of throughput Gain

Zdenek Becvar,Pavel Mach

doi:10.1155/2013/615072

Abstract

A deployment of femtocells to mobile wireless networks can increase a throughput of indoor as well as outdoor users. On the other hand, it introduces several problems such as serious interference or high number of performed handovers. This paper is focused on mitigation of redundant handovers to femtocells with open or hybrid access. The redundant handovers decrease user's throughput due to a management overhead and due to introduced interruption. We design a novel handover decision algorithm based on an estimation of throughput gain reached by a handover to a femtocell. In the proposal, the handover is initiated only if the estimated gain in user's throughput exceeds a predefined threshold. As the results indicate, high ratio of eliminated redundant handovers is achieved by the designed procedure. Moreover, a drop in user's throughput due to the handover procedure is reduced by the proposed algorithm and thus the user's throughput is increased.

Highlights

Femtocells are deployed to improve signal quality in buildings or to offload a Macro Base Station (MBS)
This paper provides a solution for efficient elimination of redundant handovers in networks with Femto Access Point (FAP) if advantage of the coordination among the MBSs and the FAPs via backbone is exploited
The distance dUE − FAP is distributed for each dMBS − FAP

Summary

Introduction

Femtocells are deployed to improve signal quality in buildings or to offload a Macro Base Station (MBS). Three types of user’s accesses can be provided by the FAP: open, closed, and hybrid. In case of the open access, all users under coverage of the FAP can connect to it. A benefit of the open access consists in an opportunity to offload the MBS by serving several outdoor users in areas with heavy traffic load or by serving users far from the MBS [1]. The hybrid access is a combination of both It means, a part of FAP’s transmission capacity is dedicated for the CSG users and the rest of the bandwidth can be shared by other users. As presented in [2], the open access provides higher mean throughput experienced by users when compared to the closed one for low densities of user. Closed access is preferred for high density of the MBS’s users [3]

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Discussion

Conclusion