A Low Profile Wideband Linearly Polarized Slot Antenna Using a Circular AMC Surface

In this paper, a novel low-profile wideband linearly polarized slot antenna based on an artificial magnetic conductor (AMC) reflector is designed. It consists of an elliptical slot antenna and an AMC reflector consisting of 4 × 5 slotted circular patches. The [-90°, +90
^o
] in-phase reflection bandwidth of the AMC is 5.68 - 8.52 GHz (40%). Utilizing the in-phase reflection of the AMC surface, the spatial phase delay caused by the air layer between the upper antenna and the lower AMC reflector is reduced, so that the profile of the antenna is reduced compared with the antenna using a metal reflector. The measured and simulated results show that the antenna has an impedance bandwidth of 5.06 - 7.92 GHz (44.07%), a peak gain of 8.05 dBi, a 3-dB gain bandwidth of 5.3 - 7.3 GHz (31.7%), and a height of 0.101 λ
L
(λ
L
is the wavelength at the lowest operating frequency).