Compact Dual-Polarized Cross-Slot Antenna With Colocated Feeding

In this communication, a dual-polarized cross-slot antenna is proposed with a relative small dimension. Orthogonal polarizations with high port isolation are provided by the cross-slot structure. A dualmode colocated feeding network is properly integrated with the cross slot, without occupying extra area. Therefore, the overall dimension of the proposed antenna is only 0.293λ 0 × 0.293λ 0 × 0.008λ 0 (λ 0 is the free space wavelength at center frequency). A prototype is fabricated and measured to prove the design strategy. In such a compact antenna volume, the -10 dB impedance bandwidths for both orthogonal polarizations are over 6%, with the port isolation better than 30 dB and radiation efficiency over 68%, exhibiting potential applications in space-limited systems, such as access points and portable base stations.