Search

This study introduces a wide bandwidth and wide axial ratio (AR), circularly polarised (CP), patch array antenna. By combining dual layers of a polarizer with dual layers of linearly polarized microstrip patch antenna, a novel method is created for generating circular polarization waves with a wide frequency range. The dual-layer 2 × 2 and 2 × 8 microstrip patch array antenna is employed to achieve linearly polarized waves and the external polarizer consists of a 3 × 3 and 3 × 12 four-layer dual rings polarizer that transforms linearly polarized (LP) waves into CP waves. The |S11| −10 dB bandwidth of small and large-scale circular polarized array antennas is 20% and 27.06% at 5 GHz, respectively, Simulations and testing show that the 3-dB axial ratio bandwidth (ARBW) at 5 GHz is 17%. The suggested antenna has a lot of potential for satellite communication applications because of its easy structure, wide ARBW, and wide impedance bandwidth. [ABSTRACT FROM AUTHOR]

Designing an ultra-wideband array antenna for fifth generation (5G) is challenging for the antenna designing community because of the highly fragmented electromagnetic spectrum. To overcome bandwidth limitations, several millimeter-wave bands for 5G and beyond applications are considered; as a result, many antenna arrays have been proposed during the past decades. This paper aims to explore recent developments and techniques regarding a specific type of phased array antenna used in 5G applications, called current sheet array (CSA). CSA consists of capacitively coupled elements placed over a ground plane, with mutual coupling intentionally introduced in a controlled manner between the elements. CSA concept evolved and led to the realization of new array antennas with multiple octaves of bandwidth. In this review article, we provide a comprehensive overview of the existing works in this line of research. We analyze and discuss various aspects of the proposed array antennas with the wideband and wide-scan operation. Additionally, we discuss the significance of the phased array antenna in 5G communication. Moreover, we describe the current research challenges and future directions for CSA-based phased array antennas. [ABSTRACT FROM AUTHOR]

A low‐profile wide‐scan phased array for 28 GHz 5G band operation, based on the current sheet array (CSA) concept, is presented in this work. The array is dual‐polarized with horizontally and vertically polarized dipoles are placed in close proximity to leverage intentional capacitive coupling. A meta‐surface based on fully split rings is printed on the top of the matching layer, contributing to wide‐scan performance. A capacitive metallic plate is placed below the cross‐section formed between orthogonal dipole elements to subdue the in‐band coupled‐loop modes. The design is demonstrated to operate at 26–30 GHz with voltage standing wave ratio (VSWR) <3 for ±60° scanning in principal planes, with a low‐profile 0.26λh. The simulations are validated by measuring an 8 × 8 array prototype, which shows good agreement with the simulated predictions. [ABSTRACT FROM AUTHOR]

A new efficient aggregate basis function method is proposed for the electromagnetic scattering from composite structures consisting of finite periodic array and other object. The aggregate basis functions composed of Rao–Wilton–Glisson basis functions are defined, which leads to a good decrease in the number of unknowns, but with the enough accuracy. To obtain the aggregate basis functions, the approximate solution is implemented. By taking advantage of the nature of periodic array, the filling number of the impedance matrix blocks is substantially decreased, and the procedure of getting the approximate solutions is accelerated. The accuracy and efficiency of the proposed method are demonstrated in a typical scattering example. [ABSTRACT FROM AUTHOR]