Broadband impedance transformers

摘要

The invention concerns an impedance transforming device that includes a dielectric circuit board substrate. The substrate has at least one region that has a relative permeability or a relative permittivity different from a remaining portion of the substrate. In order to control the permeability and permittivity, in this way, meta-materials can be used to selectively modify portions of the substrate. A transmission line transformer is disposed on the substrate and coupled to the region.