An Ultrawideband and Low-Profile Phased Array Design for Satellite-assisted Internet of Things Vehicular Communication

This article presents a low-profile dual-polarized phased array antenna featuring an improved feed structure and a multiresonant wide-angle impedance matching (WAIM) layer for satellite-assisted Internet-of-Things (SATA-IoT) vehicular communications across the L-, S-, C-, and X-bands. First, an improved feed structure based on a double-sided multi-notch balun (DMB) is developed to provide stable impedance transformation and tailored field distribution, thereby enhancing impedance matching in the low- and mid-frequency bands. Second, a planar nonuniform metasurface (PNM)-based multiresonant WAIM layer is introduced. By properly engineering its effective permittivity and permeability, two desired resonances together with inductive coupling are achieved, enabling wide-angle scanning performance in the high-frequency band. These two key techniques jointly allow the proposed array to realize ultrawide bandwidth, wide-angle scanning capability, and a low-profile configuration. To validate the design, a 5×5 prototype was fabricated and measured. The measured results show a 9:1 impedance bandwidth from 1.4 to 12.6 GHz. In particular, both array configurations exhibit an active VSWR below 3 at broadside, and maintain active VSWR below 3.3 for scan angles up to ±70° across the entire operating band. The overall profile is only 0.075 λlow. These results demonstrate that the proposed array is a promising candidate for SATA-IoT and related vehicular IoT communication systems.