DISPERSION CHARACTERISTICS OF LiTi-FERRITE RADOME

摘要

The dispersion characteristics of a magnetically switchable LiTi-Ferrite radome is presented. A thin layer of LiTi-ferrite is used as superstrate or radome layer, which control the radiation, reception, and scattering from a printed antenna or array by applying a DC magnetic bias field in the plane of the ferrite, orthogonal to the RF magnetic field. In this analysis, absorbing and transmission power coefficients are calculated to obtain the power loss in radome layer and transmitted power, respectively. The absorbing power coefficient verifies the switching behavior of radome for certain range of applied external magnetic field (H_o), which depends on the resonance width parameter (ΔH) of ferrite material. By properly choosing the bias field, quasi TEM wave propagation in the ferrite layer can be made to be zero or negative over a certain frequency range, results in a switching behavior in the ferrite layer.