An ultra-wideband high-gain slot antenna with a constant beamwidth on the E-plane

An ultra-wideband high-gain slot antenna providing constant beamwidth on the E-plane is presented in the paper. It uses a lotus-shaped slot and a reflector below the slot to achieve constant beamwidth in the entire bandwidth. The simulation conclusions confirm that the bandwidth of the proposed antenna is expanded by 86.6% (1.29 GHz to 3.26 GHz) by adopting a new type of lotus-shaped slot. The proposed slot antenna with an E-plane half-power beamwidth of 60±5° and a realized gain of 7.92 dBi to 10.49 dBi in the entire band is achieved by placing the reflector. The suggested antenna is suitable for future ultra-wideband applications due to its high gain, ultra-wide bandwidth, consistent patterns, low profile, and simple construction.