Energy Consumption Optimization in Cell-Free Massive MIMO Systems With Hybrid Energy Supply

With the development of communications technology and the massive deployment of communications equipment, the energy burden on communications networks is becoming increasingly severe. Energy harvesting (EH) technology can be used to collect green energy from the environment for access points (APs) in a cell-free massive multiple-input multiple-output (CF-mMIMO) system. Due to the hybrid power supply, different APs receive energy unevenly, which may result in green energy waste and thus higher grid energy consumption. With regard to this, we allow energy transmission through the smart grid in our system and formulate a problem of minimizing grid energy consumption while satisfying the quality of service (QoS) demands of users, where energy management and power control (PC) are taken into consideration jointly. Then, we propose a scheme based on the soft actor-critic (SAC) algorithm to intelligently schedule network resources, whose reward function is designed to achieve QoS guarantees and minimize grid power consumption. Simulation results show that our method has significant potential to reduce grid energy consumption in uneven energy distribution scenarios and offers a runtime advantage over iterative algorithms.