Performance Analysis of an Energy Efficient Femtocell Network Using Queuing Theory WANOD KUMAR*, PARDEEP KUMAR**, AND IRFAN AHMED HALEPOTO* RECEIVED ON 28.04.2013 ACCEPTED ON 05.06.2013 ABSTRACT The energy expenditure of cellular networks is increasing rapidly due to high demand of data services by the subscribers. This subsequently gives rise to the CO 2 emission which is a critical issue nowadays. A hybrid cellular network comprised of macrocell and several femtocells is required to achieve reliability, continuous connectivity, and energy efficiency. To address the issue of energy efficiency, in this paper we present a queuing model of an energy efficient femtocell network. The transmission of data traffic in this type of network is modeled using M/M/1 queue where server FAP (Femtocell Access Point) takes vacation to save energy during inactivity period. The network model is solved using a MGM (Matrix Geometric Method). The performance of the system is evaluated in terms of average system delay and power savings for different sleep cycle durations. Results reveal that the maximum energy can be saved with higher sleep cycle duration at a cost of increased system delay. Key Words: Cellular Network, Energy Efficiency, Femtocell, Matrix Geometric Method, Sleep Cycle, Queuing, Quality of Service. * Assistant Professor, Department of Electronic Engineering, Mehran University of Engineering & Technology, Jamshoro. ** Assistant Professor, Department of Computer Systems Engineering, Quaid-e-Awam University of Engineering, Science & Technology, Nawabshah. 1. INTRODUCTION Recently, a growing interest has been seen for reducing the carbon footprint. In this regard, the reduction of the CO 2 emission has been committed by various developed and developing economies [6]. For example the United Kingdom has decided to reduce its carbon emission level to only 20% by 2050. Currently the contribution of cellular communication to the total emission is only 1-2%. However, with rapid growth in the data service required by the cellular subscribers, the CO 2 emission is expected to increase with a pretty high pace. To address this issue, many researchers from academia and industry are putting Mehran University Research Journal of Engineering & Technology, Volume 32, No. 3, July, 2013 [ISSN 0254-7821] 535 T he capacity of wireless cellular networks can be increased by deploying small cells such as femtocells along with existing macrocells [1,2]. This kind of deployment has mainly two advantages: first high link reliability is achieved and second the spatial reuse is increased [3]. The femtocell networks support short range indoor communication hence the disadvantage of receiving weak signals from a macro- basestation can be avoided [4]. Moreover, the femtocell based deployment can enable a continuous wireless broadband communication in cellular dead zones [5].