Novel impedance matching approach employing the band gap region of composite right/left-handed artificial lines

In this paper we describe a new way to use composite right/left-handed (CRLH) artificial lines for matching purposes. The novelty of this approach is to include the usage of the band gap of the CRLH line as operation region. Including this region extends the classic transmission line transformer theory to the most general case, enabling matching of arbitrary impedances. The basic theory is presented and exemplary applied. A real microstrip line implementation is designed, built and measured as demonstration. The comparison to circuit and full wave EM simulations is done, showing good agreement.