High‐gain high‐selectivity TE20‐mode SIW‐fed metasurface filtenna array for 5G millimeter‐wave applications

Abstract

AbstractA high‐gain high‐selectivity 4 × 4 metasurface (MS) filtenna array is presented in this paper for 5G millimeter‐wave (mmW) applications. The TE20‐mode substrate integrated waveguide (SIW) with two parallel coupling slots is applied as the differential feeding structure, which can produce a wide impedance bandwidth and good radiation performances, simultaneously. Additionally, the TE20‐mode SIW feeding line is well designed to operate as a λ/2 short‐circuited line at the upper edge frequency to gain a radiation null. Meanwhile, a folded U‐shaped slot is etched on each MS unit to generate a radiation null at the lower edge. As a result, a passband which covers our 5G mmW band (24.25–29.5 GHz) of interest can be realized. To validate the design, a 4 × 4 MS filtenna array was manufactured and measured. The simulated and measured results are in good agreement, demonstrating a −10 dB impedance bandwidth of 19.8%, a flat gain variation with a maximum value of 19.82 dBi, symmetrical radiation patterns, low cross‐polarization levels of –30 dB, and high out‐of‐band rejection levels of 25 dB.