Electromagnetic Energy Scavanging – REC-EM

This project involves the energy harvesting and RF-DC conversion from electromagnetic energy. Improving energy independence of active and intelligent communicating objects for industrial applications is described here.
Today there is a steady increase in the number of intelligent communicating objects in our environment. For example, the number of sensors will continue to increase over the coming years and for multiple applications (environmental monitoring, security, health). One of the problems often cited comes from the energy dependence of these systems with respect to the electrical network. Added to this, the aim to reduce as much as possible the costly wired connections and batteries.
An attractive solution is to recover the RF energy from a controlled source and convert it into DC power so as to activate the sensor as needed and not permanently. This particular device is called rectenna (as rectifying antenna).
However, this well-known solution exhibits several problems:
-the variation of the conversion efficiency which quantifies the performance of a rectenna must be stabilized and regulated. It oscillates when the input signal varies (for example, this is due to the mismatch between antennas or disalignment ...) which can cause disabling actuators or sensors.
-the development of compact printed antennas dedicated of a rectenna array. This configuration is necessary when power levels are too higher (sensors, actuators ...). Most antennas are printed in a conventional forms (square, rectangular ...) and cannot be integrated into devices with small dimensions. The design of small antennas will be also discussed.
-the choice of structural organisation of the rectenna (serie, parallel or cascaded...) depending on the application and the association of the antenna with its rectifier device is today empirically obtained. However, the configurations must be designed using dedicated numerical tools to maximize conversion efficiency and minimize the total radiated power,
-numerical simulation tools must be developed in the study to finely describe the behavior of the studied rectennas. As such, the simulator will incorporate both a circuit approach (for electronic components) and electromagnetic (for transmission lines and radiation effects). This is the global simulation. Similarly, we must define several criteria for optimization (for a simple rectenna or array of rectennas) and integrated it into commercial software as well as developed in the laboratory.
-Finally, the development of experimental devices and demonstrators throughout the project will be widely promoted. This is a necessary step to enhance both academic and industrial, and validate the relevance of the results obtained by simulation.

The proposed project is based on the overlap of two areas. The antennas to capture the electromagnetic waves and power electronics, although the field levels are lower.
The proposed team has been already formed due to his interest in the subject. The various participants are also currently involved in a contract funded by the Research Foundation for Aviation and Space on the same theme (Wave-Supply, 2007-2010).