An omnidirectional antenna array is proposed in this paper. The antenna unit of the array is composed of ten radiation patches and the associated microstrip feeding network. Some gaps between top and back patches are introduced in the antenna to improve matching, ease of feeding and enhance the bandwidth. Microwave experiments and numerical simulations are performed to demonstrate antenna functionalities. The fabricated antenna exhibits a bandwidth of 14% (1-1.15 GHz) for VSWR ≤ 1.5, with a gain around 6 dBi. The results are valuable for the design and evaluation of omnidirectional planar antenna arrays with good impedance matching, which are important for airborne and navigation applications.
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