A novel artificial magnetic material based on a CPW series-connected resonator and its implementation in original applications

In this paper, a new class of artificial magnetic materials (AMMs) based on a modified uniplanar series resonator folded to form a close-loop inclusion which contains a distributed capacitance and inductance is introduced. Many advantages of the proposed design over conventional split ring resonators are discussed. The resonant frequency at which a banstop region occurs due to the presence of negative effective permeability in the dielectric slab of the host transmission line near the resonance is calculated and compared with simulated results. Two prototype microwave devices are provided to illustrate the potentiality of the proposed inclusion; The first design represents a dual-band bandstop filter with a designed center band frequencies at 1.8 GHz and 2.4 GHz, the lumped element model of this filter contains four series-connected parallel LC resonators which are implemented using our high Q-factor AMMs patterned on the backside of a CPW transmission line. The second device is a miniaturized hybrid branch line coupler operates at 2.4 GHz; based on a special loading technique that increases the electric length of transmission lines by patterning the ground plane under the conductor trace in microstrip lines with the complementary, dual-behavior, configuration of AMMs, a miniaturization factor up to 18.41 % is achieved compared to the conventional couplers. For both design examples the simulated responses show their high performance which validates our work.