Resonance characteristics of CPS open-loop resonator

A novel coplanar stripline (CPS) open-loop resonator (OLR) is proposed for maximum miniaturization in uniplanar microwave applications. In addition, the effect of variation in the one's width of longer strips of OLR (namely, CPS fixed gap (FG) OLR) that is realized by cutting a gap into the one of the longer strips, oriented along the direction of propagation, of the standard loop on their resonance characteristics is discussed. It is shown that the resonance frequency of this novel resonator is almost half that of the standard CPS loop resonator. Also, simple empirical expressions indicating the effect of variation in the strip width are derived for estimation of the resonance frequency as a function of the variable strip width and the fundamental resonance frequency of the standard CPS loop resonator. This novel resonator is first simulated using a full-wave EM simulator and, then realized on RT/Duroid substrates. Also, the comparison of the simulated and measured results is made, and good agreement is observed between them.