Patent ID: 6801173
Filing Date: 2004-10-05
Classification: H01Q

Abstract:
A structure with switchable magnetic properties comprising: an array of capacitive elements, the array exhibiting a predetermined magnetic permeability in response to incident electromagnetic radiation lying within a predetermined frequency band, in which each capacitive element includes a low resistance conducting path and is such that a magnetic component of the electromagnetic radiation lying within the predetermined frequency band induces an electrical current to flow around said path and through said associated element, wherein the spacing of the elements is less than the wavelength of the radiation within the predetermined frequency band, wherein the size of the elements and their spacing apart are selected such as to provide the predetermined permeability in response to received electromagnetic radiation, and wherein each capacitive element comprises at least two concentric spiral conducting members which are electrically insulated from each other and which have a switchable permittivity material therebetween.