Broadband CPW-Fed Aperture Coupled Metasurface Antenna

In this letter, a printed broadband metasurface (MTS) antenna fed by an aperture coupling through a coplanar waveguide (CPW) is introduced. To achieve the wideband impedance matching, a technique of loading an MTS radiator formed by nonuniform patch elements above a stair-shape aperture is applied. The stair-shape aperture is attached to the end of the CPW. The proposed antenna is simple and low-profile in structure, which can be realized by a single-layer printed circuit board (PCB) substrate. To verify the concept, a prototype with an overall size of 1.28 λ₀ × 1.28 λ₀ × 0.09 λ₀, where λ₀ is the free-space wavelength at 7 GHz, is fabricated. The proposed antenna realizes a wide impedance bandwidth of 67.3% with reflection coefficient ≤ -10 dB and peak gain of 9.18 dBi. The measurement results agree well with the anticipation.