Date Added: Sep 2012
The Long Term Evolution-Advanced (LTE-Advanced) networks are being developed to provide mobile broadband services for the Fourth Generation (4G) cellular wireless systems. Device-To-device (D2D) communications is a promising technique to provide wireless peer-to-peer services and enhance spectrum utilization in the LTE-Advanced networks. In D2D communications, the User Equipments (UEs) are allowed to directly communicate between each other by reusing the cellular resources rather than using uplink and downlink resources in the cellular mode when communicating via the base station. However, enabling D2D communications in a cellular network poses two major challenges. First, the interference caused to the cellular users by D2D devices could critically affect the performances of the cellular devices. Second, the minimum Quality-of-Service (QoS) requirements of D2D communications need to be guaranteed.