Composite right/left-handed wideband metamaterial antenna loaded with SRRs and CSRRs to improve gain and efficiency

摘要

A coplanar waveguide-fed metamaterial antenna is presented. The proposed antenna is composed of two-unit cell composite right/left-handed transmission line (CRLH-TL) loaded with split ring resonators (SRRs) and complementary SRRs (CSRRs). The wideband characteristic is obtained by merging the three closely spaced resonances of CRLH-TL. The loading of SRRs and CSRRs not only improves the impedance matching but also enhances the overall gain and radiation efficiency. The measured results show a -10 dB fractional bandwidth of 67% (6.48-13 GHz) with the realised gains of 2.98, 3.43, 3.15, 2.75 and 2.61 dBi at the resonant frequencies 8.3, 9.2, 10.3, 11 and 12 GHz, respectively. The radiation efficiency is above 67% over the entire band of operation with a peak value of 81.72%. The measured results agree well with the simulated results. The proposed antenna is suitable for X-band (8-12 GHz) applications.