Design of A Ku-band Corrugated Horn With Good-Symmetrical Pattern

A good-symmetrical Ku-band corrugated horn feed with small diameter for directional radiation is proposed in this paper which is composed of a corrugated radiator and a mode converter. To concentrate the impedance transformation, 15 radial grooves are curved inside the horn. And the mode converter is slotted in the radial direction where the corresponding groove depth is changed from $\lambda/2$ to $\lambda/4$ to realize the conversion from TE11to HE11. Then, the converted HE11mode is transmitted to the corrugated horn and a good directional pattern is obtain. To verify the design, a horn prototype is fabricated and measured. The measured results show that the VSWR is 1.2:1 covering the range from 12.25 to 15.5 GHz and the good symmetry of the patterns are also gotten, while the simulations indicate the designed horn has low side lobes.