A Low-Profile Dual-Mode Slot-Patch Antenna for 5G Millimeter-Wave Applications

In this letter, a novel dual-mode slot-patch antenna is proposed in the Ka-band. Resonant modes of a slot and four patches are merged for widening the bandwidth of the low-profile antenna that is fed by an open-ended substrate integrated coaxial line. The design with a profile of 0.05λ₀ achieves a wide bandwidth of 27.5% and stable unidirectional radiation patterns. Based on the proposed antenna, a 1 × 8 array with an unequal power feeding network is designed and measured, which demonstrates an impedance bandwidth of 23%, a gain of up to 15.4 dBi, and the sidelobe level of lower than −18 dB. Benefitted from the desirable geometric and operating characteristics, the presented slot-patch antenna is suitable for 5G millimeter-wave applications.