Smaller resonators for artificial magnetic surfaces

Artificial magnetic surfaces have interesting applications in antenna design where one wants to replace, over a limited frequency range, electric conducting surfaces with magnetic equivalents. One of the many challenges in constructing such a surface is that of miniaturizing the resonator elements making up the structure whilst at the same time maintaining a reasonable bandwidth and a tolerable level of dielectric and copper losses. In this paper we present some novel structures, fabricated using chemical etching techniques, which have only 6.5% of the area of a capacitive loaded loop (CLL) and less than 30% of the area of spiral resonators and have measured return losses of less than 1.5 dB.