Compact multiband antenna employing wideband dual ZOR for mobile handset applications

In this study, a compact multiband antenna employing a wideband dual zeroth-order resonator (ZOR) is proposed for mobile handset applications. The theory of wideband zeroth-order mode and multimode is used to design the proposed antenna covering LTE850/900 (824-960 MHz), LTE1700/1800/1900/2100 (1710-2170 MHz), LTE2300 (2300-2400 MHz), LTE2600 (2500-2690 MHz), and Wi-Fi (2400-2500 MHz) bands. In order to achieve wideband operations, the proposed antenna consists of a low-band ZOR and a high-band ZOR that can generate and merge resonance frequencies of zeroth-order, negative-order, and positive-order modes. The performance of the antenna is verified by both full-wave simulations and experiments. The overall size of the antenna is 40mm×6mm×3mm. The antenna provides omnidirectional radiation patterns and measured radiation efficiencies exceeding 43% and 47% for low and high bands, respectively.