An FR4-based Dual-Mode Stacked Patch Antenna with Upper Out-of-Band Suppression Using SISL Technology

A dual-mode stacked patch antenna with upper out-of-band suppression using FR4 and the substrate integrated suspended line (SISL) technology is proposed in this paper. A driven patch with a slot and a parasitic patch constitute the proposed antenna. The driven patch generates the main resonance point at 3.45 GHz. The utilization of the parasitic patch not only broadens the impedance bandwidth of the patch antenna but also introduces extra resonance points in-band and a high-band radiation null. Due to etching a slot on the driven patch, the impedance matching is improved and dual modes in the band are obtained. As a result, the bandwidth from 3.28 GHz to 3.65 GHz is obtained for 5G applications, 8.68 dBi is achieved for the realized gain of the antenna. Besides, the high-band radiation null is 3.77 GHz and the upper suppression level is better than 15.4 dB.