CST官方资料——左手材料s.pdfVIP

Left-Handed Wave Propagation of a Coplanar Waveguide based on Split Ring Resonators Due to the absence of LHMs in nature, a LHM medium has to be artificially fabricated. This can be achieved by micro- structuring a material in a length scale shorter than a wavelength, so that a continuous medium wth effectice permittivity and permeability is obtained. The famous concept of SRR is used here and is described in further detail in [1]. Various concepts are described and also measurement setups to operate in desired frequency bands. The measurement setup is modeled and simulated by CST MICROWAVE STUDIO® (CST MWS) : The model consists of of single SRR placed inside a circular aperture made in a metallic screen placed in a piece of recantangular waveguide as shown in Fig.1. Figure 1: Model setup for simulating the SRRs magnetic polarizabilities An edge-coupled SRR design was used in this simulation model and Fig. 2 presents a typical simulation result with a peak of S21 at the SRRs resonance. Left-Handed Wave Propagation of a Coplanar Waveguide based on Split Ring Resonators © 2006 CST GmbH - Page 1 of 5 Figure 2: A typical response of the S-parameters The proposed implementation of a left-handed structure [2] is depicted in Fig.3: It consits of a host ordinary coplanar waveguide (CPW). SRRs are symmetrically placed in the back side of the substrate. Thin wires connect the signal-line to the grounded sidelines of the CPW at coincident positions with the SRRs centers, shown in Fig. 3. Figure 3: CST-MWS Model of the SRR-based LH - CPW. The dispersion relation given for a lumped element circuit model described in [2] forms a narrow pass band just above the resonant frequency of the rings. Since the wave propagation constant beta