Evaluation of Absorber Reflectivity using a Directive Antenna Array

When designing an anechoic chamber, it can be of particular advantage to develop a proper model of RF absorber. Using the model it is possible to calculate absorber reflectivity in magnitude and phase, for various angles of incidence, for parallel and perpendicular polarizations. Absorber data sheets commonly specify only the magnitude of the absorber reflectivity for normal incidence. For all other relevant data it is more convenient to use simulation instead of measurements. The paper presents a method for evaluation of absorber reflectivity illuminated by an antenna array, using full wave simulation.