Metallic Compound Air-Fed Array Antennas for Cost-Effective Microwave Radio-Link Applications

A novel structure of metallic compound air-fed array (M-CAFA) antennas, as one kind of improved Fabry-Perot resonator (FPR), is proposed in this letter. With a stepped metallic ground plate, metallic grating cover, and open-ended waveguide as the feeder, this antenna exhibits the merits of low profile, low cost, and easy integration onto outdoor unit of microwave radio-link. Its operation principle, simulation analysis, and design procedure are presented. Also, an experimental prototype of around 13 GHz is fabricated with measured results as peak gain (directivity) of 19.2 dBi, common bandwidth of 3.85% for both 3-dB gain-drop and VSWR ≤ 1.5:1, and good radiation characteristics.