Building materials are often incorporated into complex, multi-layer macrostructures that are simply not amenable to measurements using coax or waveguide sample holders. In response to this, an ultra-wideband free-field measurement system has been developed. This measurement system uses a ground-plane based system and two TEM half-horn antennas to transmit and receive the RF signal. The material samples are placed between the antennas and reflection and transmission measurements are made. Digital signal processing techniques are then applied to minimize environmental and systematic effects. The processed data are compared to a plane-wave model to extract the material properties using optimization software based on genetic algorithms.
Citation: Journal of Research (NIST JRES) -
NIST Pub Series: Journal of Research (NIST JRES)
Pub Type: NIST Pubs
digital signal processing, free-field measurement system, genetic algorithm, ground-plane, material properties, optimization, plane-wave model, reflection, TEM half-horn antennas, transmission, ultra-wideband