A compact metamaterial-based horizontally polarized omnidirectional antenna array

Abstract

A metamaterial-based horizontally polarized omnidirectional antenna array using zero phase-shift-line loop element is proposed. The antenna with an overall size of 40 mm × 40 mm × 230 mm shows desirable performance over the frequency range of 2.35-2.55 GHz with return loss larger than 10 dB, gain greater than 6 dBi, and omnidirectivity less than ± 2.3 dB.