Autonomous battery less sensor for IoT applications in Smart Buildings

Autonomous battery less sensor for IoT applications in Smart Buildings: Low-power Energy Conversion and Storage for RF Energy Harvesting

Bosma, Detmer (TU Delft Electrical Engineering, Mathematics and Computer Science)
Lindeman, Pim (TU Delft Electrical Engineering, Mathematics and Computer Science)

de Graaf, G. (mentor)
Schmitz, J.E.J. (graduation committee)
Hamdioui, S. (graduation committee)
Lager, I.E. (graduation committee)

Delft University of Technology

Electrical Engineering

2018-07-02

This report discusses one part of a project consisting of three parts. The goal of the project is to design a battery less sensor powered by RF energy fields present in an office environment. The sensor is able to measure the temperature and is able to communicate wirelessly using a low power communication protocol.In this report the energy conversion and storage of the system will be discussed. A high-frequency signal coming from an antenna must be converted to an output signal which is functional for the communication module. Therefore a steady 3.3 V DC output needed to be created with a rectifier circuit. In order to achieve maximum power transfer to the load, a matching circuit with the RF energy harvesting antenna needed to be designed. The main challenges were to achieve a high enough input voltage to reach the threshold voltage of the diodes of the rectifier and to rectify the AC input as efficient as possible. To tackle these challenges a design with a Greinacher rectifier with low-threshold Schottky diodes and a DC/DC booster is presented.

RF energy
Schottky diode
Rectifier
Impedance matching
Voltage booster

http://resolver.tudelft.nl/uuid:48996653-d2bc-43d4-b1be-5fe63092d4a9

Student theses

bachelor thesis

© 2018 Detmer Bosma, Pim Lindeman