Energy-efficient power allocation for delay-sensitive traffic over wireless systems

Energy-efficient communication becomes increasingly important for wireless communication systems partially due to the fact that the improvement in battery technology is much slower than the increase for processing power and energy consumption of electronic devices. On the other hand, the telecommunication industry predicts that the mobile data traffic will double almost every year for the next five years with more than two thirds of the future traffic being video. Since many of the video applications are delay-sensitive, it is extremely important to consider energy-efficient design for delay-sensitive traffics over wireless systems. This paper addresses resource allocation for maximizing the energy-efficiency of a wireless link under statistical quality of service (QoS) constraints. In the energy-efficiency analysis, both circuit power and transmission power of a communication system are taken into account. The joint impact of statistical QoS constraints, transmission power, and spectral bandwidth are considered. The unique globally optimal power allocation scheme is characterized. The intuition of the optimal strategy is obtained by looking at both low signal-to-noise ratio (SNR) regime and high SNR regime.