Composite right-/left-handed coplanar waveguides loaded with split ring resonators and their application to high-pass filters

In this study, it is demonstrated that coplanar waveguides periodically loaded with split ring resonators (SRRs) and shunt connected elements can be applied to the synthesis of composite right-/left-handed transmission lines with very good high-pass filter characteristics. By balancing the line and forcing the characteristic impedance around the transition frequency to be in the vicinity of 50 Ω, a broad transmission band with low insertion losses is obtained. Owing to the presence of the transmission zero to the left of the left-handed band, severe cut-off is also obtained. A prototype high-pass filter device has been designed, fabricated and characterised to illustrate the possibilities of the approach.