The System And Applications Of Wireless Rechargeable Sensor Networks

Sensor nodes in low-power wireless sensor network are powered by batteries, which leads to the finite lifetime of sensor node as well as the wireless sensor netwoks. To get rid of the battery from sensor node, a wireless rechargeable sensor network was proposed here. The sensor node in this kind of network can harvest energy from RF (Radio Frequency). The mian work of this paper is given as follows.(1) Hardware design of sensor node. The sensor node is passive, powering up with energy harvested from RF. There are mainly five parts of the sensor node: antenna module, analog front end module, microcontroller module, sensors module and (de-)modulation module. The antenna and analog front end module are used to harvest energy as well as microcontroller module is in charge of the data computation. The (de-)modulation module functions as communication in this network.(2) Construct the wireless rechargeable sensor network. The reader and sensor node can communicate with each other, and the EPC C1G2 standard is the communication being used. Due to the multi-path and scale fading, the Friis equation is not applicable in the reality. As a result, we propose a correction equation to describe the model of energy tranmitted wirelessly, and extensive experiment has been done to validate the wireless recharging model. An application of wireless rechargeable sensor networks has also been proposed, it is an intelligent access control system which based on the accelerometer in the wireless recharging sensor node.(3) Analyze the quality of monitoring in wireless rechargeable sensor network. The wireless recharging sensor node is capable of sensing, thus we can properly dispose nodes to monitor the area which we are interested in. The quality of monitoring is the important indicator of sensor networks, and we can impove it by managing the energy of reader and sensor node. We propose three wake-up strategies in wireless rechargeable sensor network, and gvie the theoritical analysis and numerical simulation following the performance comparison.