Cross-polarization suppression for patch array antennas via generalized Kerker effects.

The generalized Kerker effect has recently gained an explosive progress in metamaterials, from the scattering management of particle clusters to the reflection and transmission manipulation of metalattices and metasurfaces. Various optical phenomena observed can be explained by the generalized Kerker effect. Due to the same nature of electromagnetic waves, we believe that the generalized Kerker effect can also be used in the microwave field. Inspired by this, in this letter we design a kind of patch array antenna to suppress the cross-polarization by interferences of multipoles. Using different far-field radiation phase symmetries of electromagnetic multipoles for the patch, the cross-polarization can be almost cancelled while the co-polarization be kept. A pair of 8×8 U-slot patch array antennas, working in a wide band (8.8 GHz-10.4 GHz), have been designed, fabricated and measured to verify our proposal. Simulated and measured results both agree well with the theory, showing more than 20 dB gain suppression of the cross-polarization, which indicates the universality of the generalized Kerker effect in electromagnetic waves.