Concept

Near and far field

Related publications (415)

Structured light generation by refractive-diffractive micro optical array illuminators

Structured light generation having broad applications in different optical fields, is the topic of this thesis. Our structured light generation strategy is based on applying periodic microoptical elements at the refraction-diffraction limit, under a focuse ...

EPFL2021

Säntis Lightning Research Facility Instrumentation

Mario Paolone, Marcos Rubinstein, Mohammad Azadifar, Antonio Sunjerga, Amirhossein Mostajabi, Carlos Alberto Romero Romero, Davide Pavanello, Abraham Rubinstein, David Smith

The Säntis Tower was instrumented in May 2010 to measure currents of lightning discharges striking the tower. Since then the system has been recurrently updated and expanded. Currently, data associated with lightning strikes to the tower are collected at f ...

2021

Structured light engineering using a photonic nanojet

Toralf Scharf, Maryam Yousefi, Daniel Necesal

In this Letter, we present the photonic nanojet as a phenomenon in a structured light generator system that is implemented to modify the source focal spot size and emission angle. The optical system comprises a microlens array that is illuminated by a focu ...

OPTICAL SOC AMER2021

A Compact Transformation Optics-based Luneburg Lens Antenna using Curved Reactive Impedance Surface

Anja Skrivervik, Yuanyan Su

This paper is to investigate the pattern distortion that happens in the extremely low incidence angle for a flat TM-polarized half Luneburg lens antenna (HLLA) by using a purely reactive impedance surface (RIS). For the scenario of a radar mounted on an un ...

IEEE2021

On the Apparent Non-Uniqueness of the Electromagnetic Field Components of Return Strokes Revisited

Marcos Rubinstein, Farhad Rachidi-Haeri

Recent research work shows that there are four procedures that can be used to calculate the electromagnetic fields from a current source. These different procedures, even though producing the same total field, give rise to field components that differ from ...

2021

On the Complete Radiation Pattern of a Vertical Hertzian Dipole Above a Low-Loss Ground

Krzysztof Michalski

The complete radiation field pattern of a vertical Hertzian dipole antenna on or above a lossless or low-loss dielectric half-space is studied using a rigorous Sommerfeld formalism. The reflected fields in the air above the interface and the subsurface fie ...

Piscataway2021

An Extension of the Guided Wave M‐Component Model Taking Into Account the Presence of a Tall Strike Object

Marcos Rubinstein, Mohammad Azadifar, Qi Li, Mi Zhou

We present in this paper an extension of the guided-wave M-component model of Rakov et al. considering the presence of a vertically elevated strike object. The tall object is represented as a lossless, uniform transmission line. Expressions for the current ...

2021

The Birth of a New Field: Memristive Sensors. A Review

Sandro Carrara

Over the last 11 years, the field of Memristive Sensors abruptly emerged in literature. The present review paper has the aim to acknowledge such an exciting new field of research as well as to critically review its most significant outcomes. As usual in sc ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2021

Dipole-Fed Rectangular Dielectric Resonator Antennas for Magnetic Resonance Imaging at 7 T: The Impact of Quasi-Transverse Electric Modes on Transmit Field Distribution

Rolf Gruetter, Daniel Wenz

Shortened dipole antennas based on rectangular dielectric blocks play an important role in ultrahigh field magnetic resonance imaging (UHF-MRI) radio frequency (RF) coil design. However, the generally assumed direct contact with the subject is difficult to ...

2021

Modified Transmission Line Model with a Current Attenuation Function Derived from the Lightning Radiation Field—MTLD Model

Marcos Rubinstein, Farhad Rachidi-Haeri

In return strokes, the parameters that can be measured are the channel base current and the return stroke speed. For this reason, many return stroke models have been developed with these two parameters, among others, as inputs. Here, we concentrate on the ...

2021

Graph Chatbot

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.