Abstract: Today we are living in the era of mobile technology. Every third day new mobile technology develops. The load on the cellular network is increasing day by day and it will more and more increasing. Due to the increasing no. of mobile subscribers, demand of the mobile customers is increasing on per day basis. Customers need high data speed, lower call rate and many more services. To fulfill this demand of the customers cellular operators are trying to integrate small cells. Small cells operate at very low power and these are very Energy efficient. Small cells such as femtocell are very reliable and low range, low power cell, it operate in licensed spectrum with the range of 10m. to 3km. Femtocell are almost ten times smaller than a big mobile macrocell network. In this paper, we have used a two tier femtocell network which increases the capacity and coverage. Here, sleeping strategy is used to increase energy efficiency of the network.

Keywords: Energy Efficiency, Power Consumption, Two tier Network, Sleeping strategy.