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The purpose of this brief is to present a two-dimensional wideband and wide beam-steering phased array antenna with a combined superstrate. The arched metal columns are incorporated in the dipole array antenna to suppress the mutual coupling, resulting in wideband matching and wide beamwidth characteristics in the ${E}$ -plane. A combined superstrate, comprising metasurface slabs and a dielectric layer, is located above the antenna to increase the beamwidth and enhance the impedance matching property. The same effect can be achieved by optimizing the curvature of the exponential curves of the dipole edge to obtain a deformed dipole. To showcase the wideband wide-scanning capability of the device, a prototype is designed with a scanning range of ±60° in both the ${E}$ - and ${H}$ - plane at 2.5-4.75 GHz (62.1%, active VSWR $\leq 2$ ). The simulated co-polarization gain of the array is close to the ideal aperture, which decreases no more than 3 dB in large-angle scanning. To ascertain the viability of the proposed design, an $8\times 8$ prototype is manufactured and subjected to testing. The overall dimension is $2.23\lambda _{0}\times 2.23\lambda _{0}\times 0.24\lambda _{0}\,\,(\lambda _{0}$ is the free space wavelength at 2.5 GHz). Based on the findings of the experiment, there is a good concurrence between the design and measurement outcomes. The proposed array demonstrates the advantages of low-cost, broadband, and wide beam-steering capability, which is expected to be suitable for the implementation of fifth-generation (5G) communication systems.

This article presents a dual-polarized wide-angle scanning phased array antenna for 5G application. This antenna has the properties of compact structure, orthogonal polarization, and low elevation coverage. The parasitic metal columns are used to suppress the abnormal resonance and improve the beamwidth of the elements. Bent frame metal arms are applied to make a compact element size of $0.37\times 0.37\times 0.33\lambda _{0}^{3}$ (where $\lambda _{0}$ represents the center frequency wavelength), which further broadens the beamwidth of the antenna element and optimizes the active reflection coefficients for large-angle scanning within the operating frequency band. Subsequently, a $6\times 6$ antenna array prototype based on the proposed element is designed and fabricated. The measured results indicate that the operational frequency band of the array spans from 3.0 to 3.8 GHz, and a wide scanning angle of ±80° can be achieved with a gain fluctuation below 7 dB. The measured results are closely correlated with the simulated ones, which confirms the effectiveness of the proposed design for wide-angle scanning.

A wide-angle scanning array based on a new pattern-reconfigurable element (PRE) is presented. The PRE is formed by docking two modified coupling planar inverted F-shaped antennas, one as the main element and the other as a parasitic element. Amplitude and phase perturbations are attached to the binary array, forming a tilt pattern and a wide operating band. A 1 × 8 antenna array based on the PRE is designed. The active patterns tilt gradually with the increase of frequency, suppressing the grating lobes appearing at low elevations and realizing wide-angle scanning under a large spacing. The special bias circuitry reduces the impact of additional wires on the array performance. The antenna array prototype was manufactured and measured to verify the design. The dimension is 3.93λ0 × 0.61λ0 × 0.08λ0 (λ0 is the free-space wavelength at 4.1 GHz). The main lobe realized ±70° scanning range at 3.75–4.5 GHz (18.3%) with a gain fluctuation within 3.2 dB. The maximum sidelobe levels remain below −7.2 dB during scanning. The cross-polarization levels are kept below −45 dB. The measurement is consistent with the simulated results.