An electronically reconfigurable reflectarray that can operate in dual linear and dual circular polarization modes with simultaneous beam scanning capability is introduced. The highlight of this work is that only 1-bit phase resolution is used to achieve quad-polarization conversion phase shift through array arrangement, which greatly reduces the system complexity.

This work presents unique measurements of sky-noise temperature and atmospheric attenuation up to W-band and in all-weather conditions available from the only two sites in the world equipped with a Sun-tracking microwave radiometer. The large and robust database allowed the design of an innovative atmospheric model for non-geostationary satellite links.

Inverse source formulations are key elements of antenna design procedures. This work’s contributions are twofold: we propose a Love inverse source formulation requiring half-the-size matrices, clearly leading to substantial computational savings; we also propose the first stabilization of the Steklov-Poincare operator using projectors. This paves the way to wide band applications of otherwise only high frequency schemes, something very relevant for biomedical imaging such as neuroimaging.

A novel 7m x 1.5m parabolic cylinder foldable/deployable mesh reflector antenna with tensegrity configuration and unprecedentedly low stow-volume and mass is designed, prototyped, and measured for the global mapping of Earth's Surface Deformation and Change (SDC) using space-based small satellite remote-sensing synthetic aperture radar (SAR) in Low-Earth orbit.

This is the first large-scale indoor assessment of the Smart ElectroMagnetic Environment (SEME) paradigm using static passive EM skins (SP-EMSs) to enhance 5GHz Wi-Fi coverage mimicking a realistic user-experience. Proofs of the effectiveness as well as economic benefits of the SEME deployment with respect to the densification of active radiating sources are provided.

Modulated metasurfaces are able to realize a low-profile antenna with multiple beams. The present work proposes a new method to reduce mutual interference of different impedance modulations corresponding to different beams. As a result, it is the first time that seven beams are radiated by a single modulated metasurface using seven ports.

A dual-band antenna for metal-bezel smartwatches, achieving circular polarization in GPS band via a capacitor, is introduced. A simple metal plane is proposed to significantly mitigate the negative effect from human wrist and enhance antenna efficiency and stability, thus making the presented antenna promising for practical applications.

A novel solution for designing planar endfire antennas with wide bandwidth and compact physical apertures is introduced. By leveraging trapped waves supported by metasurfaces, we overcome existing design challenges. This work contributes to advancing antenna technology, enabling enhanced performance in wireless communication systems and paving the way for innovative applications.

Parallel plate slot array antenna suffers from low aperture efficiency due to the intrinsic multi-mode feature of the oversized waveguide. In this study, a novel feeding network with centered-longitudinal slots is proposed for reducing the field ripples in the parallel plates, which significantly improves the aperture efficiency.

Exploring a dual-band high-gain antenna with a small footprint and lightweight is essential and always a primary choice in many potential applications, particularly satellite-based communication systems for simultaneous data streams in full-duplex. The proposed work is the first realization of a near-field phase correction metascreen operating in the Ku bands. A fully metallic slot-based architecture with high structural integrity is devised, significantly reducing cost, weight, and fabrication complexity. The elimination of dielectrics also enhances the capability to avoid typical issues encountered by dielectric materials in space and high-power applications, such as radiation damage, degassing, carbonization, and dielectric breakdown.

Real-time information interaction among vehicles and other devices is essential for autonomous driving. To overcome disadvantages of installing several separated antennas on a common platform, a compact multifunctional antenna with concurrent broadside RHCP for V2S communication and bidirectional end-fire LP radiation for V2X communication is presented.

A piezoelectric crystal is employed together with appropriate metallic boundaries to build efficient EM radiators by utilizing piezoelectric effect in antenna engineering. The radiation efficiency of a demonstrated prototype exceeds the upper limit of metallic antennas.

Few designs, to date, can realize the integration of MW PIFA antenna and broadside MMW beam-steering array. The proposed antenna fills this gap by using a uniform substrate, achieving a high integration level with a small clearance of only 7mm. In this design, the MMW SIDRA, which is a 1×4 connected DRA array, is developed in the clearance area of the PIFA.

Inherent loss in practical materials hinders achieving accurate radiation patterns in printed metasurface antennas. The paper proposes a modulated metasurface leaky-wave antenna design technique that accurately accounts for dielectric and conductor losses. Based on penetrable aperture field synthesis, the design is capable of realizing various radiation patterns accurately.

A novel 5G air-to-ground (ATG) array for aviation applications is realized through reconfigurable technique. The reduced cross-sectional area, full azimuth coverage and low complexity of the array provides significant advantages over conventional solutions. The array design is beneficial in promoting the future 5G applications.

Reducing the number of antennas in a radar front-end will result in reducing the number of RF channels, thereby reducing cost and power consumption. We overcome the difficulty of degrading the performance of the radar due to the reduced number of antennas and propose a highly efficient algorithm to guide the aperiodic arrangement.

Specifications for satellite communication require an ultra-wideband antenna with a high gain and high efficiency. In this study, an ultra-wideband cavity-backed antenna that covers uplink and downlink bands for Ku-band direct broadcasting devices (DBS) is proposed, which results in weight reduction, especially for unmanned aerial vehicles (UAV).

Enhanced circularly-polarized radiation, under the condition that the structural compatibility with the existing protective dome shell embodied by the truncated icosahedron is taken into account, is achieved through a hemispherical metasurface. The dome, capable of radiation conversion, can facilitate the link enhancement while the system’s compactness and skin curvature are well retained.

This paper presents lower Q-factor bounds for microstrip patch antennas, orders of magnitude tighter than the Chu limit. These bounds provide achievable bandwidth benchmarks and a guide to assess required design parameters. An easy-to-compute approximation of these bounds is also proposed.

A typical leaky-wave antenna (LWA) and its natural frequency-scanned beam are inevitably subject to the narrowband characteristic towards a certain spatial angle. This would impede LWAs from being deployed for wideband systems such as modern radars needing good range resolutions or communications requiring high transmission rates. Our research is structured under such background, providing the feasibility of augmenting the application versatilities of LWAs and facilitating them to be potentially exploited for wideband wireless systems.