Related papers: High-efficiency, Wideband GRIN Lenses with Intrins…
We propose a general method for designing wideband matching tapers in inhomogeneous media where phase velocity is coupled to the taper impedance profile. Such tapers are used to match wideband gradient index (GRIN) lens antennas. To…
We present the design, simulation, and planned fabrication process of a flat high resistivity silicon gradient index (GRIN) lens for millimeter and submillimeter wavelengths with very low absorption losses. The gradient index is created by…
Artificial dielectrics are widely used for Gradient-Index (GRIN) lens antennas. The unit-cell size of an artificial dielectric determines the maximum operating frequency and also drives cost and yield. To explore the frequency limitations…
Despite the growing interest in reconfigurable intelligent surfaces (RISs) for millimeter-wave (mm-wave) bands, and the considerable theoretical work reported by the communication community, there is a limited number of published works…
Compact and efficient optical antennas are fundamental components for many applications, including high-density fiber-chip coupling and optical phased arrays. Here we present the design of grating-based micro-antennas with perfectly…
We present the design, fabrication and characterisation of a broadband leaky lens antenna for broadband, spectroscopic imaging applications. The antenna is designed for operation in the 300-900 GHz band. We integrate the antenna directly…
In this work, a method is presented to maximize the obtained gain from millimeter-wave (mm-wave) lens antennas using phase center analysis. Commonly, for designing a lens antenna, the lens is positioned just on top of the antenna element…
Large imaging arrays of detectors at millimeter and submillimeter wavelengths have applications that include measurements of the faint polarization signal in the Cosmic Microwave Background (CMB), and submillimeter astrophysics. We are…
The requirement of high data-rate in the fifth generation wireless systems (5G) calls for the ultimate utilization of the wide bandwidth in the mmWave frequency band. Researchers seeking to compensate for mmWave's high path loss and to…
In this paper, a two-dimensional cylindrical Lens antenna based on the parallel plate technique is designed. It supports beam-steering capability of 58 degree at 28 GHz. The antenna is composed of low loss rectangular waveguide antennas,…
We report subwavelength-thick, polarization insensitive micro-lenses operating at telecom wavelength with focal spots as small as 0.57 wavelengths and measured focusing efficiency up to 82%. The lens design is based on high contrast…
Many works in elasticity have exploited the concept of gradient index (GRIN) lenses, borrowed from optics, for wave focusing and control. These effects are particularly attractive for cloaking, absorption or energy harvesting applications.…
Lens-based beam-forming antennas offer a low-power, low-cost alternative to hybrid beamforming antenna arrays. They are ideally suited to millimeter-wave massive MIMO systems due to their native beam-space operation and angular selectivity…
A novel and simple approach to optical wavelength measurement is presented in this paper. The working principle is demonstrated using a tunable waveguide micro ring resonator and single photodiode. The initial calibration is done with a set…
High-gain antennas are essential hardware devices, powering numerous daily applications, including distant point-to-point communications, safety radars, and many others. While a common approach to elevate gain is to enlarge an antenna…
In fifth-generation (5G) communication, the RF lens antenna is introduced with advantages of high antenna gain and low hardware cost in analog/digital hybrid beamforming technology. In this paper, we design and manufacture the appropriate…
Massive multiple-input multiple-output (MIMO) techniques have been recently advanced to tremendously improve the performance of wireless communication networks. However, the use of very large antenna arrays at the base stations (BSs) brings…
In this paper, we investigate a radio frequency (RF) lens-embedded massive multiple-input multiple-output (MIMO) system and evaluate the system performance of limited feedback by utilizing a technique for generating a suitable codebook for…
We present the design, fabrication, and characterization of a 100 mm diameter, flat, gradient-index (GRIN) lens fabricated with high-resistivity silicon, combined with a three-layer anti-reflection (AR) structure optimized for 160-355 GHz.…
Grating magneto-optical traps are an enabling quantum technology for portable metrological devices with ultracold atoms. However, beam diffraction efficiency and angle are affected by wavelength, creating a single-optic design challenge for…