Fraunhofer Institute for High Frequency Physics and Radar Techniques FHREven in the information age, obtaining the required data is not always straightforward — for example, the electromagnetic material parameters needed for antennas in high‑frequency engineering. A web‑based catalog is now intended to provide these parameters from a single, unified source for the first time.
The range of materials that can be used for high‑frequency applications is extensive: various magnetic, dielectric, conductive, and absorbing materials come into consideration. Each of them possesses entirely unique material parameters. These parameters must be known with high accuracy, particularly for simulations of antenna structures, feed networks, and platforms for high‑frequency applications; otherwise, the simulation results would lack precision. A further challenge is that material parameters vary with frequency — sometimes significantly, sometimes more moderately, depending on the material. Only limited information on the electromagnetic behavior of materials can be found in simulation tools, publications, and datasheets. Information on new materials is currently scarce. Moreover, for most materials only a few key values are provided — leaving extrapolation as the only option for other frequencies, even though such extrapolations can deviate substantially from reality. The same applies to the behavior of materials under varying temperature conditions.
Measurement of Parameters at Fraunhofer FHR
Fraunhofer FHR offers the capability to measure the characteristic parameters of individual materials using different setups and across various frequency ranges. However, such measurements are complex and costly: the equipment must first be calibrated, the setup must then be validated using additional reference materials, and the material must be measured multiple times to estimate measurement uncertainty.
Web‑Based Catalog
In a web‑based catalog, researchers at Fraunhofer FHR are compiling all determined parameters — including measurement uncertainties — for the first time..The basic structure of the database is already in place, as is a prototype of the web interface. Parameters for 15 materials have already been entered, with the number steadily increasing. The database is currently hosted on a test server, but in the coming months it will be made accessible to the entire Fraunhofer FHR. Researchers will then be able to compare materials or search specifically for materials with certain characteristics.