Dual-Polarized Filtering Antenna With Printed Jerusalem-Cross Radiator

This paper presents a design of dual-polarized antenna with embedded filtering circuits by using a printed Jerusalem-cross radiator and a ring slot-coupled feed structure. A square ring slot has been adopted to implement the coupling mechanism. It is excited by two orthogonal microstrip feedlines to achieve dual polarizations. Meanwhile, the slot-coupled feed network and printed Jerusalem-cross radiator form a coupled-resonator circuit that realizes a second-order bandpass filtering performance. Consequently, a dual-polarized antenna with a filtering performance is obtained without using extra filtering circuits. To demonstrate the idea, an antenna prototype operating at LTE bands 42 and 43 (3.4-3.8 GHz) is designed, fabricated, and measured. Measured results show that the proposed antenna provides good filtering and dual-polarized radiation performances. Furthermore, a four-element dual-polarized linear array is designed for high-gain applications.