Related papers: High-efficiency, Wideband GRIN Lenses with Intrins…
A microwave lens with highly reduced reflectance, as compared to conventional dielectric lenses, is proposed. The lens is based on two-dimensional or three-dimensional transmission-line networks that can be designed to have an effective…
The miniaturisation of optical systems is an ongoing challenge across the electromagnetic spectrum. While the thickness of optical elements themselves can be reduced using advances in metamaterials, it is the voids between these elements --…
The symmetry matching between the source and the lens results of fundamental interest for lensing applications. In this work we have modeled an axisymmetric gradient index (GRIN) lens made of rigid toroidal scatterers embedded in air…
Multi-beam radar sensing systems are emerging as powerful tools for non-contact motion tracking and vital-sign monitoring in healthcare environments. This paper presents the design and experimental validation of a synchronized…
One-dimensional light harvesting structures illuminated by a conventional lens are studied in this paper. Our theoretical study shows that high transmission efficiencies are obtained when the structure is placed near the focal plane of the…
Modern communication systems will require antennas with adaptive functionality which are able to modify their performance based on the requirements of the channel. For example, mobile ad-hoc networks need directive antennas that are able to…
A multi-beam antenna with a dual band operation in the 28 GHz and 31 GHz millimeter wave band is presented. The antenna has a gain of around 15 dBi in each of the three ports. The spatial footprint of the antenna is 166 mm x 123 mm x 34 mm.…
This study presents a prospective concept of a mechanically reconfigurable Gradient Index (GRIN) lens for focusing and beamforming applications. The lens is formed by corrugated layers, each realizing a refractive index profile expressed in…
Conventional surface-relief gratings are inefficient at deflecting normally-incident light by large angles. This constrains their use in many applications and limits the overall efficiency of any optical instrument integrating gratings.…
In this paper, a new composite right/left-handed (CRLH) Leaky Wave Antenna (LWA) based on substrate-integrated waveguide (SIW) structures is proposed. The suggested antenna has a continuous beam scanning from backward to forward versus…
Rotman lens is a true-time-delay beam forming network with parallel plate structure. Owing to its frequency- independency and wide-band operation, it has gained vast applications as feeding element of linear array antennas. However, the…
Locally resonant elastic metamaterials (LREM) can be designed, by optimizing the geometry of the constituent self-repeating unit cells, to potentially damp out vibration in selected frequency ranges, thus yielding desired bandgaps. However,…
This paper introduces a highly efficient rectenna (rectifying antenna) using a binary optimization algorithm. A novel pixelated receiving antenna has been developed to match the diode impedance of a rectifier, eliminating the need for a…
We present a new spatial-spectral mapping technique permitting to measure the beam intensity at the output of a graded-index (GRIN) multimode fiber with sub-nanometric spectral resolution. We apply this method to visualize the fine…
In this paper we present the design of a flat-base Luneburg type of lens antenna, designed for wide angle scan. The antenna consists of a 11-layer lens, fed at its base by a 6x6 array of waveguides. The lens is broadband and has a high…
Silicon photonics has thrived in telecommunications over recent decades, and its extension to the mid-infrared range has the potential to unlock valuable opportunities for sensing, imaging, and free-space communications. With this…
This manuscript presents an ultra-wideband Microstrip multiple-input-multiple-output (MIMO) antenna covering the 2.4GHz to 6.5 GHz wireless local networks (WLAN) and Sub-6G bands. The applied MIMO antenna is composed of two symmetrical…
Efficient coupling between integrated optical waveguides and optical fibers is essential to the success of integrated photonics. While many solutions exist, perfectly vertical grating couplers which scatter light out of a waveguide in the…
Massive multiple-input multiple-output (MIMO) techniques have been recently advanced to tremendously improve the performance of wireless networks. However, the use of very large antenna arrays brings new issues, such as the significantly…
Realizing capacity demands of future wireless communications requires improved spectral efficiency in the sub-6-GHz frequency bands. This paper proposes a novel eight-element multiple-input multiple-output (MIMO) antenna that can be tuned…