NSF Award
9661186
*** 9661186 Read This Phase I Small Business Innovation Research project will develop novel microwave absorbing materials that effectively absorb microwave radiation over wide ranges of frequency (typically an octave). The absorbers are based on materials that have dielectric properties that are functions of frequency in such a mariner as to create strong, wideband absorption from a fixed thickness of material. The typical thicknesses are appropriate for cast, flexible sheets and bulk forms, and compositions with higher dielectric constant suitable for paints are also possible. The microwave loss and the majority of the real part of the dielectric constant in these materials result from a strong, non-exponential dielectric relaxation associated with the micro-geometry of a tailored ceramic-conductor composite. The frequency response of the absorbers is adjustable by chemical means during the processing of the composite. Test samples of these materials will be synthesized and the favorable frequency response and tunability will be demonstrated experimentally. Potential applications include the suppression of spurious emissions and interference from consumer communications and computer equipment, and suppression of oscillations in microwave power tubes, and passive microwave strip line components. If very thin materials can be developed, there are additional applications in military systems. ***
