Design Of Nodes And Energy Harvesting System In Wireless Sensor Network

An energy harvesting system is designed to prolong the life of the Wireless Sensor Network(WSN) under the background of power management in the WSN. A proper network topology applying to a specific application is presented in the thesis.Firstly the design of a node in the WSN is presented, forming a basic platform to do the research. The node utilizes a module from the Atmel Corporation as its core component. A light sensor, a humidity and temperature sensor and a microphone are on the node. This supplies the hardware platform for the later research in the control algorithm and application. Then the power dissipation of the whole node is analysed to supply the application with a data reference.Secondly, the thesis introduces the well-known protocol stack Zig Bee and Bitcloud which is a protocol stack based on Zig Bee. The basic operating process of the protocol stack and the implemention of the power management are presented and analysed. This makes a foundation for designing the power management algorithm.Thirdly, after the preparation of hardware and software, the design of an energy harvesting system is presented. To improve the output energy of the solar cell, a control circuit and a control algorithm based on the light condition are presented. Both of them are used for the Maximum Power Point Tracking(MPPT) of the solar cell. Then the improved system is simulated.Finally, considering the practical application, acoustic shooter localization, a network topology and a node grouping strategy are designed. The power dissipation and the life of the whole network is analysed, referring to the energy harvesting system and the power management algorithm discussed in the previous contents. The calculation results show that the whole network is able to live for a long time due to utilizing the energy harvesting system.