Broadband Epsilon Negative Transmission Line Resonant Antenna with AIS Loading

A metamaterial-based broadband antenna loaded with artificial impedance surface (AIS) is presented in this letter. Two metallic vias connect a Y-shaped patch to the ground plane. The patch, two metallic vias, and the AIS compose an epsilon negative (ENG) transmission line (TL). The asymmetry Y-shaped patch and the AIS bring about the first-order resonance (FOR) and second-order resonance (SOR) modes, which can be merged into one passband to yield a wideband property. The proposed ENG-TL resonant antenna has the advantages of compact size, wide bandwidth, and high gain, which can be applied to portable and handheld communication system.