Design of a Compact Dual-Band Double-Stub Matching Network Using MTM-EBGs

This work proposes a novel method of rendering a double-stub tuner dual-band through the introduction of embedded, metamaterial-based electromagnetic bandgap structures (MTM-EBGs). The MTM-EBG, which has predictable dispersion characteristics and is both compact and uniplanar, effectively changes tuner's stub lengths as a function of frequency, allowing matching of a
$50-\Omega$
source impedance to an arbitrary, frequency-dependent load at two frequency bands, while maintaining a size no larger than the corresponding single-band double-stub tuners. The dual-band, double-stub matching network operates comparably to conventional single-band structures, with return loss of over 20 dB observed in each band.