A collaborative wireless power transfer technique for wireless rechargeable sensor networks

Abstract

Wireless sensor network is a network system of sensor devices that are deployed randomly in a particular area. Usually hundreds or more nodes deployed in an area, these sensor devices are autonomous and small in size. A base station (BS) collects data from sensor nodes and processes it. The sensor nodes are connected wirelessly with BS forwards their data to it. Major functions of a WSN include sensing, processing and forwarding useful data and make it an autonomous organized network. The use of WSN in many applications required very complex computation in sensors, which make it highly energy driven network [1], so in order to prolong network lifetime, energy conservation is considered as one of the main research focus for the last decade. Significant efforts are needed to replace sensors batteries, which is difficult in some circumstances (e.g. hazardous areas), where the deployed sensors are difficult to access. Network lifetime can be prolonged for continuous operations, if sensor’s battery can be improved [1]. The technique to transfer energy wirelessly has been adopted by wireless rechargeable sensor networks (WRSNs). It tackles energy limitation problem efficiently. It aims to increase network lifetime by transferring power to end devices. The time taken to charge a sensor node is one of the major issue in research. Existing schemes to charge include wireless power transfer and energy harvesting technique. Although, these schemes aim to charge wireless devices, however they incur high delay. In this document we propose a scheduling technique to transfer power wirelessly. This scheme maximizes network lifetime by serving more charging requests in less time