Sustainable Energy Harvesting Wireless Sensor Networks Energy Modeling And Optimization

With the continuous deepening of the research on energy harvesting technology, wireless sensor nodes equipped with energy harvesting equipment can provide better energy solutions for wireless sensor networks. Energy harvesting wireless sensor networks(EH-WSNs) overcome many shortcomings of the traditional wireless sensor networks: limited battery storage capacity, unpredictable battery life and high maintenance costs, therefore, it has gradually become one of the focus of efforts to explore and research in recent years. Energy harvesting wireless sensor nodes with energy harvesting device, such as solar panels, continuously collect energy from the environment and convert solar energy into electrical energy, as a stable power supply for wireless sensor nodes. Theoretically, if energy harvesting power of the wireless sensor node is always greater than energy consumption power, it can guarantee the energy sustainability, making the life cycle of the wireless sensor nodes to infinite and without manual maintenance, and solve the inherent defects of traditional wireless sensor nodes once and for all.The theoretical research of this paper is mainly focused on the fixed solarpowered wireless sensor networks, and respectively from the point of optimizing energy collection efficiency and optimizing energy scheduling strategy, mainly involves two aspects of the content: Firstly, according to the randomness and uncertainty of the solar energy collection characteristics, based on the law of solar light incidence and energy calculation model, in this paper we put forward the deployment and optimization strategy for solar-powered wireless sensor nodes with arbitrary location and time interval, so that the energy harvesting efficiency can be optimal; Secondly, according to the determined node deployment strategy, and the energy consumption pattern of ultra low power wireless sensor nodes, in this paper we designed the node energy management model, and on this basis, designed and implemented the node dynamic energy scheduling algorithm: the dynamic dutycycle algorithm and the energy redistribution algorithm.Based on the above research content, in this paper we design and implement the solar-powered wireless sensor node deployment and scheduling system. The system mainly consists of three modules: network monitoring module, node deployment and optimization strategy module and dynamic energy scheduling module. Network monitoring module, as the remote terminal of solar-powered wireless sensor networks, can connect to the wireless sensor network through the UART serial port, and display the entire wireless sensor network sensing information and working state in real time; Node deployment and optimization strategy module is mainly for the node deployment and optimization strategy, according to a series of user specified parameters. Based on sunny or non-sunny energy calculation model, it can generate the deployment strategy of solar-powered wireless sensor nodes and the energy distribution within the starting and ending time; Dynamic energy scheduling module is directly related to application program on node-level, and displays the topology of the wireless sensor network and the energy scheduling status of the node in real time. As a part of the energy scheduling module, in this paper we design and implement the embedded dynamic energy scheduling algorithms on node-level: the dynamic duty-cycle algorithm and the energy redistribution algorithm, and the rationality of the algorithms is verified according to the real experimental data.