Programmable Sensor Transponders
Fraunhofer Institute for Photonic Microsystems
- Development kit for UHF transponder with reader, antenna and tag.
This working group focuses on the research and development of systems with wireless signal and energy transmission. To this end, the group develops innovative transponder circuits. They use ISO standard protocols for communication, and can thus be operated with a variety of readers. Solutions are available for all established frequencies. Applications in liquids are also possible for magnetically coupled systems in the range of 125 kHz and 13.56 MHz. The distance between the sensor and the reader can be up to half a meter. Electromagnetic coupled systems in the UHF range (850 to 950 MHz) and the microwave range at 2.45 GHz feature a range of coverage of several meters. Sensors are integrated or can be connected via analog and digital interfaces. The option of adapting the program to the relevant application is a special feature of all systems. It means that the systems can be used for a variety of applications. Semi-active systems are available for applications with data logger function.
The scope of work also includes the establishment of transponder systems with antenna adaptations for various ambient conditions, and the development of firmware on the transponder and the application software of the reader. The RFID systems of Fraunhofer IPMS are also used in transport logistics, micro implants and for monitoring equipment and for long-term monitoring purposes.
For more information on our RFID activities and current reader software, please visit www.rfid-sensor-plattform.de.
Current Research Topics
- Monitoring Temperatures in Switch Boxes of the company Köhl.
- Hip prosthesis with integrated sensor system.
The UHF transponder circuit from Fraunhofer IPMS can be used to build wireless, passive RFID systems with sensors. It is possible to connect batteries for systems with the data logger function. Ranges of coverage of several meters are possible depending on the transmission power, size of the antenna and the energy requirements of the connected sensors. As one example, the company Köhl uses this transponder system in switch boxes (current of 3000 A, many metal parts) for monitoring temperatures.
The development of microsystems engineering has made it possible to equip medical implants with measurement and monitoring functions. Transponder technology can be used for the required energy supply within the body. Using the transponder circuit ST1 from Fraunhofer IPMS on the basis of the carrier circuit of 125 KHz, a microsystem was integrated into the ceramic ball of a hip prosthesis in order to record the loosening of the prosthesis. The prosthesis swings in the bone on the basis of an external mechanical stimulus. The microsystem determines the resonance frequency of the system and hence the state of loosening.