Compact antenna based on a composite right/left-handed transmission line

ABSTRACT This letter presents a novel antenna that is based on composite right/left‐handed (CRLH) transmission line unit‐cells implemented using slots and spiral inductors that are etched directly on the dielectric substrate by standard manufacturing techniques. The antenna is designed to operate across 5.8–7.3 GHz, which corresponds to a fractional bandwidth of 23%. Measured results confirm the antenna exhibits a relatively wide bandwidth, high gain, and high radiation efficiency characteristics. The measured radiation gain, bandwidth, and efficiency of the antenna at 6.6 GHz are 4.8 dBi, 23%, and 78%, respectively. The fabricated antenna is highly compact and its physical size in terms of the free‐space wavelength is 0.39λ0 × 0.13λ0 × 0.015λ0. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1785–1788, 2015