Chapters authored
Radio Frequency Energy Harvesting - Sources and Techniques
Energy harvesting technology is attracting huge attention and holds a promising future for generating electrical power. This process offers various environmentally friendly alternative energy sources. Especially, radio frequency (RF) energy has interesting key attributes that make it very attractive for low-power consumer electronics and wireless sensor networks (WSNs). Ambient RF energy could be provided by commercial RF broadcasting stations such as TV, GSM, Wi-Fi, or radar. In this study, particular attention is given to radio frequency energy harvesting (RFEH) as a green technology, which is very suitable for overcoming problems related to wireless sensor nodes located in harsh environments or inaccessible places. The aim of this paper is to review the progress achievements, the current approaches, and the future directions in the field of RF harvesting energy. Therefore, our aim is to provide RF energy harvesting techniques that open the possibility to power directly electronics or recharge secondary batteries. As a result, this overview is expected to lead to relevant techniques for developing an efficient RF energy harvesting system.
Part of the book: Renewable Energy
Optimal Temperature Sensor Based on a Sensitive Material
The context of this chapter is the development of passive sensors for temperature sensing applications. The purpose is to successfully reduce the energy consumption in wireless sensor networks. The sensor is based on the electromagnetic transduction principle, and its originality is based on the integration of a high temperature-sensitive material into passive structure. Variation in temperature makes the dielectric constant of this material changing, and such modification induces variation in the resonant frequencies of high-Q whispering-gallery modes in the millimeter-wave frequency range. In this way, the proposed device shows a linear response to the increasing temperature, and these variations can be remotely detected from a radar interrogation of an antenna loaded by the whispering-gallery mode resonator. Proposed device is a powerful tool for many interesting applications since it offers very low power consumption and provides environmentally friendly temperature measurement. The sensor is simulated in order to outline its performance and to show the benefit of the batteryless sensing device.
Part of the book: Perovskite and Piezoelectric Materials