Phased Array With Pattern Shaping and Scan Loss Reduction for Millimeter Waves

In this work, we investigate antenna architectures to implement dual-mode operation in phased array designs. Planar slot antenna elements are used in array configuration, in combination with artificial dielectrics layers (ADLs) located in the close proximity of the array, to achieve pattern shaping. The artificial dielectric superstrate...

Dielectric Gratings Enhancing the Field of View in Low Dielectric Permittivity Elliptical Lenses

Low relative permittivity plastic elliptical lenses in combination with integrated focal plane arrays are a promising solution to be used in the future mm- and sub-mm-wave systems. Their appeal lies in the availability of materials with moderate loss and lightweight, and the possibility to use cost-effective manufacturing techniques. However,...

A Fourier Optics Tool to Derive the Plane Wave Spectrum of Quasi-Optical Systems [EM Programmer's Notebook]

We present a freely accessible graphical user interface (GUI) for analyzing antenna-fed quasi-optical (QO) systems in reception (Rx). This analysis is presented here for four widely used canonical QO components: parabolic reflectors and elliptical, extended hemispherical, and hyperbolic lenses. The employed methods are geometrical optics (GO)...

Wideband Circularly Polarized Antenna with In-Lens Polarizer for High-Speed Communications

In this contribution, a broadband G-band leaky-wave (LW) fed lens antenna with an integrated dielectric grid polarizer is presented. The proposed wideband polarizer unit cell geometry enables its fabrication at frequencies higher than 100 GHz, presenting high transmission properties and low axial ratio (AR). A quasi-Analytic technique based...

Coherent Fourier Optics Model for the Synthesis of Large Format Lens Based Focal Plane Arrays

Future sub millimeter imagers are being developed with large focal plane arrays (FPAs) of lenses to increase the field of view (FoV) and the imaging speed. A full-wave electromagnetic analysis of such arrays is numerically cumbersome and time-consuming. This article presents a spectral technique based on Fourier optics combined with...

A GO/FO Tool for Analyzing Quasi-Optical Systems in Reception

In this work, a free accessible MATLAB interface is presented to analyze antenna-coupled Quasi-Optical (QO) systems in reception. This goal is achieved by using Fourier Optics (FO) and Geometrical Optics (GO) based methods. Specifically, the FO method represents the field focalized by a QO component on its focal plane as a plane wave spectrum...

Dielectric-Grating In-Lens Polarizer for beyond 5G Communications

A high-gain broadband leaky-wave fed lens antenna with an integrated dielectric gratings polarizer covering the whole G-band (140-220GHz) is presented. This work focuses on the polarizer gratings manufacturing and in particular on the selection of plastic materials and the fabrication process refinement. The polarizer geometry has been...

Quasi-Optical System for the ASTE Telescope with 1:3 Bandwidth at Sub-mm Wave

DESHIMA is a spectrometer for astronomical applications targeting sources at sub-mm wavelengths from 240GHz to 720GHz that will operate in the ASTE telescope in Atacama Desert, Chile. In this work, a quasi-optical system based on a hyper-hemispherical leaky lens antenna and a series of Dragonian reflectors is presented as the coupling chain...

A Connected Array of Coherent Photoconductive Pulsed Sources to Generate mW Average Power in the Submillimeter Wavelength Band

A pulsed photoconductive terahertz (THz) source is presented that is able to radiate milliwatt (mW) level average power over a large bandwidth, by exploiting both the optical and electrical properties of photoconductive sources and the ultrawideband properties of connected antenna arrays. An optical system composed of a microlenses array...

Reception Power Pattern of Distributed Absorbers in Focal Plane Arrays: A Fourier Optics Analysis

Passive imaging cameras at millimeter and submillimeter wavelengths are currently entering a new era with the development of large format arrays of direct detectors. Several of these arrays are being developed with bare absorbing meshes without any antenna coupling (lens or horn) structures. The design of such arrays is typically done...

Norton Equivalent Circuit for Pulsed Photoconductive Antennas - Part II: Experimental Validation

This second part of two papers' sequence presents the experimental validation of the Norton equivalent circuit model for pulsed photoconductive antennas (PCAs) provided in the first paper of the sequence. To this goal, different prototypes of photoconductive antenna sources have been manufactured and assembled. The average powers radiated and...

Norton Equivalent Circuit for Pulsed Photoconductive Antennas-Part I: Theoretical Model

A novel equivalent circuit for pulsed photoconductive sources is introduced for describing the coupling between the photoconductive gap and the antenna. The proposed circuit effectively describes the mechanism of feeding the antenna by the semiconductor when this latter is illuminated by a laser operating in a pulsed mode. Starting from the...

Circularly Polarized Lens Antenna for Tbps Wireless Communications

The exponentially increasing demand for highspeed wireless links can be only efficiently satisfied with the development of future XG wireless communication networks, based on higher carrier signal frequencies, starting from 100 GHz. In this contribution, a circularly polarized G-band leaky-wave fed lens antenna with an integrated dielectric...

Characterization of the THz quasi-optical channel for the measurement of the power radiated by photoconductive antennas

In this paper a rigorous electromagnetic characterization of the setup for measuring the THz power radiated by pulsed photoconductive antenna is discussed. Such characterization is expressed in terms of efficiencies which quantify how much power is lost in the coupling between the various components involved in the measurement setup. The...