Millimeter-Wave Dual-Polarized Filtering Antenna Design for 5G AiP Application

This paper presents a design method of dual-polarized millimeter-wave (mm-Wave) filtering antenna with high selectivity. The proposed antenna design consists of a differential-fed driven patch and stacked parasitic structures. The combination of the stacked structures and the driven patch can be equivalent to band-stop filtering circuits for generating radiation nulls at the stopband. Besides, additional shorted patches as band-stop structures are embedded into the driven patch for introducing other radiation nulls at the band-edges. As a result, a quasi-elliptic bandpass response is realized without requiring extra filtering circuit. Based on the above design method, two different mm-Wave filtering antennas with high roll-off rate are proposed. Both of them can be fabricated with low-cost PCB process. These merits make the proposed antenna design a good candidate for the 5G mm-Wave antenna-in-package (AiP) application to reduce the requirements of the filters in the mm-Wave RF frontends.