Energy-efficient resource allocation in wireless OFDMA systems

Reducing the consumed energy in wireless communication systems has a direct impact on operational expenditure as well as CO₂ emissions. With increasing interest in multimedia applications and high data rate services, environmentally sustainable communications networks must reduce the energy per delivered bit at an equal rate, if not better. This paper addresses downlink energy-efficient transmission in OFDMA systems and maximizes the overall bits transmitted per joule of energy. In addition to the transmit power, circuit power is also accounted for in the energy-efficient design, which is tackled using both standard optimization techniques and a frame work based on time-sharing. Simulation results show similar performances for both cases with the latter having lower complexity and taking less CPU time to run.