QoS Aware Energy Efficient Resource Allocation in HSDPA Systems

Developing green radio networks is desirable to improve energy efficiency under quality of service (QoS) constraints. In this paper, we propose a QoS aware energy efficient resource allocation scheme in multiuser high speed downlink packet access (HSDPA) systems. First, we derive a new metric, namely effective energy efficiency (EEE), to represent the delivered service bits at the media access control (MAC) layer per joule subject to given QoS constraints. Then, by using this new metric, a EEE optimization problem in the mixed traffic scenario is formulated, where we can exploit the multi-traffic diversity. With the help of primal decomposition technique, we solve the formulated problem and propose a cross-layer resource allocation scheme, in which determines the EEE optimal transmit power level for each user and schedules the set of EEE near-optimal users. Numerical results are presented to quantify the superiority of our proposed scheme over the conventional resource allocation schemes.