High-Gain Dual-Polarized Millimeter-Wave Patch Filtenna Array

A millimeter-wave (mmW) dual-polarized 4 × 4 patch filtenna array with broadband, high gain, and simplified feeding networks is presented in this letter. Two modified substrate-integrated waveguide (SIW) cavity modes in cooperation with a patch TM
₀₁
mode are stimulated in the proposed 2 × 2 filtenna subarrays to enable broadband and high gain. A simple filtering SIW feeding line is employed to improve the operating bandwidth and form a radiation null at the lower band edge. Furthermore, filtering slots are etched around each patch to introduce extra mixed electromagnetic coupling paths, thereby improving the selectivity performance of the subarray at the upper band edge. To further simplify the feeding structure, two stacked staggered 4-way power dividers are realized in the dual-polarized 4 × 4 filtenna arrays. A prototype of the proposed 4 × 4 filtenna array was fabricated and measured, demonstrating wide −10-dB impedance bandwidths of 16.5% from 25.6 to 30.2 GHz and 17.4% from 25.3 to 30.2 GHz, as well as high peak gains of 19.2 and 20.1 dBi for the two polarizations, respectively.