Research On Cell Scaling And User Scheduling For Multiuser EH-DAS

With the rapid development of 5G cellular networks and the popularization of various new devices,the data volume of wireless communication has reached an unprecedented scale.The huge demand of users for high-speed data and low-latency networks has made the coverage density of cellular networks saturated.At the same time,pollution and energy consumption problems in the communication industry have gradually become prominent.Therefore,improving transmission efficiency and reducing energy loss have gradually become the research hotspots of 5G mobile communication.Among them,Distributed Antennas System（DAS）with Energy Harvesting（EH）technology is a very promising research direction.Due to the uneven and intermittent characteristics of the energy harvesting process,this technology has certain limitations in practical applications.Therefore,how to deal with the fluctuation of EH and maintain the stability of the network needs to be studied in depth.In the work of this paper,considering the spatiotemporal dynamics of EH renewable energy power generation,from the perspective of optimizing energy efficiency（EE）,a strategy for cell scaling and user scheduling in EH-DAS is designed.The details are as follows:（1）In the downlink multi-user EH-DAS cell,in order to reduce the drop rate of users and ensure the quality of service of the communication network,a same-layer zooming strategy and user scheduling between green Remote Antenna Units（RAU）are proposed plan.The method monitors the remaining battery energy and user load of the EH-RAU in real time.For nodes and areas with unstable energy sources,the stability of the cell network is maintained by controlling node zooming and user scheduling.On this basis,EE is used as an indicator to judge the quality of the zooming scheduling strategy.In order to deal with this problem in real time,a Find DMU algorithm combined with an improved particle swarm optimization algorithm is designed to perform fast and efficient parameter optimization.MATLAB simulation results show that the proposed zooming scheduling scheme has good performance in dealing with the fluctuation of EH energy source,reducing the user disconnection rate and improving the system EE.（2）In the scenario where multiple EH nodes are simultaneously short of energy and users move,the EH-DAS cell still has the risk of user disconnection.Aiming at this problem,a two-layer cell zooming model combining grid power supply and EH power supply is proposed.At the same time,considering the mobility of users under different activity levels,the handover scheme of mobile users between nodes is designed in combination with user service quality,remaining battery power and node load.The MATLAB simulation results show that the two-layer EH-DAS zooming model can effectively deal with the simultaneous shortage of energy in multiple nodes and user movement in the cell,which makes the whole research more valuable and meaningful.