abstract This paper introduces a left-handed metamaterial traveling-wave antenna (TWA) based on metamaterial transmission-line structure to enhance the gain and radiation efficiency of the antenna without trading on its fractional bandwidth. The antenna consists of a series of coupled unit-cells comprising ¿X-shaped¿ slots which are inductively terminated to ground. Effective aperture of the antenna can be increased by increasing the number of unit-cells. The consequence of this is enhanced gain and radiation efficiency performance with no adverse affect on its fractional bandwidth. The antenna's characterizing parameters were extracted using 3D electromagnetic simulation tool (HFSS¿), and the antenna was fabricated using standard PCB manufacturing techniques on a 1.6 mm thick dielectric substrate with permittivity of 2.2. The antenna operates from 0.4 GHz to 4.7 GHz. The antenna has an electrical size of 0.017¿0 × 0.006¿0 × 0.002¿0, where ¿0 is free space wavelength at 400 MHz. The proposed antenna is significantly smaller than its conventional counterparts. Antenna's measured optimum gain and radiation efficiency are 2 dBi and 65%, respectively, at 2.5 GHz. These features make the antenna attractive for use in multiple wireless communication applications. © 2016 Elsevier GmbH
keywords broadband antenna metamaterial (mtm) traveling-wave antenna (twa) x-shaped slot bandwidth computational electromagnetics dielectric materials efficiency electric lines electromagnetic simulation metamaterial antennas metamaterials microwave antennas polychlorinated biphenyls printed circuit manufacture slot antennas substrates wireless telecommunication systems broad-band antenna fractional bandwidths free-space wavelengths left handed metamaterial metamaterial (mtm) metamaterial transmission lines shaped slots wireless communication applications traveling wave antennas