Electromagnetic wave absorber using ferrite absorbing material dispersed with short metal fibers

A broad band electromagnetic wave absorber in GHz frequency range was newly developed by two-layer construction. Each layer operates as a low-impedance resonator and an impedance transformer. For the low-impedance resonator design, a ferrite/resin mixture incorporated with short metal fibers is used. The electromagnetic wave absorber presented in this paper has a broader operation bandwidth, nearly 50 % in relative bandwidth (bandwidth more than 20 dB absorption/center frequency), than the operation bandwidth for a conventional ferrite absorber. Broadband characteristics are achieved in oblique incidence, up to nearly 45 degrees of incident angle.