A Dual-Band High-Gain Slotted Spherical Antenna Radiator

A dual-band high-gain slotted spherical antenna radiator is designed in this paper. The radiator is operating at X and Ku bands using the fundamental TM
₁₀₁
mode and the spurious TM
₂₁₁
mode of the employed spherical resonator. The radiation is achieved by interrupting surface current of the radiated modes with three slots that are symmetrically opened on the sidewall of the spherical cavity. Good radiation patterns can be achieved at two bands by properly selecting the slot dimensions. The radiator exhibits a simulated return loss of over 10 dB in the lower band from 9.97 to 10.66 GHz and in the upper band from 13.2 to 15.19 GHz with the maximum gains of 7.8 and 9.1 dBi, respectively.