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Concept

Radio atmospheric signal

Related publications (28)

Computation of the attenuation function of the lightning return-stroke current from electromagnetic fields measured in a short-duration time-window, Part I: Theoretical investigation

Farhad Rachidi-Haeri, Marcos Rubinstein

In a recent paper, a procedure to reconstruct the attenuation function of a return-stroke current from the simultaneous measurements of the channel-base current and the radiated electromagnetic fields was presented. One of the assumptions of the whole fram ...

Elsevier2023

Computation of the attenuation function of the lightning return-stroke current from electromagnetic fields measured in a short-duration time-window — Part II: Numerical implementation

Farhad Rachidi-Haeri, Marcos Rubinstein

In the present paper, we show, by means of numerical simulations, that electromagnetic field data obtained from the radiation of a return-stroke lightning discharge and measured over a short-duration time-window can be exploited to reconstruct the attenuat ...

Elsevier2023

Current propagation type self-consistent leader-return stroke model

Farhad Rachidi-Haeri, Marcos Rubinstein

A current propagation type return stroke model which is consistent with the estimated distribution of the charge on the leader channel is described. The model takes into account the dispersion of the return stroke current along the return stroke channel. T ...

Elsevier2023

Exact Expressions for Lightning Electromagnetic Fields: Application to the Rusck Field-To-Transmission Line Coupling Model

Farhad Rachidi-Haeri, Marcos Rubinstein

An exact analytical expression for the electric field of the return stroke as excited by a propagating step current source is derived in this paper. This expression could be advantageously used to evaluate the disturbances caused by lightning on overhead l ...

2023

Influence of a lossy ground on the lightning performance of overhead transmission lines

Farhad Rachidi-Haeri, Rafael Silva Alipio

This paper investigates the impact of incorporating both displacement currents and frequency-dependent soil parameters in the calculation of the ground-return impedance for the determination of the backflashover rate of 138 kV and 230 kV overhead transmiss ...

Elsevier2023

Modeling lightning strikes to tall towers

Farhad Rachidi-Haeri, Marcos Rubinstein

In this chapter, we present a review of recent progress in the modeling of lightning strikes to tall structures. Since some tall structures are struck by lightning several tens of times per year, they can be used as ground-truth to measure and calibrate th ...

IET2023

Lightning Nowcasting Using Solely Lightning Data

Farhad Rachidi-Haeri, Marcos Rubinstein, Amirhossein Mostajabi, Seyed Mohammad Ehsan Mansouri Tehrani

Lightning is directly or indirectly responsible for significant human casualties and property damage worldwide. A timely prediction of its occurrence can enable authorities and the public to take necessary precautionary actions resulting in diminishing the ...

MDPI2023

Ionospheric Variations Induced by Thunderstorms in the Central Region of Argentina during the RELAMPAGO–CACTI Campaign

Farhad Rachidi-Haeri, Marcos Rubinstein

The ionosphere can be perturbed by solar and geomagnetic activity, earthquakes, thunderstorms, etc. In particular, electromagnetic pulses produced by thunderstorms can generate wave structures in the ionospheric plasma, which are known as atmospheric gravi ...

2023

Polarity Asymmetry in Lightning Return Stroke Speed Caused by the Momentum Associated with Radiation

Farhad Rachidi-Haeri, Marcos Rubinstein

In positive lightning return strokes, the net momentum transported by the radiation field has the same direction as the momentum associated with electrons, whereas the momentum associated with electrons is in opposite direction to the momentum of radiation ...

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

A Current Propagation Type Return Stroke Model Consistent with the Leader Charge Distribution

Farhad Rachidi-Haeri, Marcos Rubinstein

We describe a current propagation type return stroke model which is consistent with the estimated distribution of the charge on the leader channel. The model takes into account the dispersion of the return stroke current along the return stroke channel. Th ...

2021

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

Juan Ramon Mosig, 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 ...

Ieee-Inst Electrical Electronics Engineers Inc2021

Lightning-Induced Voltages on Overhead Distribution Lines Computed through Analytical Expressions for the Electromagnetic Fields

Farhad Rachidi-Haeri, Marcos Rubinstein

The evaluation of lightning ElectroMagnetic (EM) fields represents the most cumbersome part of the lightning-induced voltages computation process. Their evaluation is usually performed through a numerical routine or with simplified analytical expressions, ...

2021

The Polarity Reversal of Lightning‐Generated Sky Wave

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Wenhao Hou

The polarity reversal of the lightning‐generated first sky wave as a function of the observation distance is studied using a novel approach combining the finite‐difference time domain (FDTD) method and the superposition principle of electromagnetic waves. ...

2020

An Efficient FDTD Method to Calculate Lightning Electromagnetic Fields Over Irregular Terrain Adopting the Moving Computational Domain Technique

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Wenhao Hou

We present an improved finite-difference time domain (FDTD) method based on the moving computational domain technique for the calculation of lightning-generated fields over large-scale irregular terrain. In the improved method, a spatial window moving alon ...

2020

LMA observations of upward lightning flashes at the Santis Tower initiated by nearby lightning activity

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Antonio Sunjerga, Amirhossein Mostajabi, Jacopo Grazioli, Nikola Besic

We present in this paper lightning current measurements, LMA (Lightning Mapping Array) data and fast antenna electric fields associated with upward flashes observed at the Santis Tower during summer of 2017. The LMA network consists of six stations that we ...

Elsevier2020

Pulses in Upward Negative Lightning at the Säntis Tower in Northeastern Switzerland

Farhad Rachidi-Haeri, Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Lixia He

Upward lightning happens predominantly from tall objects. The channel-base currents associated with upward negative lightning initiated from towers exhibit pulses that can be classified, based on their waveform features and on the concurrence with other pr ...

2019

The Propagation Effects of Lightning Electromagnetic Fields Over Mountainous Terrain in the Earth-Ionosphere Waveguide

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar

In this paper, a full-wave two-dimensional Finite-Difference-Time-Domain model is developed to evaluate the propagation effects of lightning electromagnetic fields over mountainous terrain in the Earth-ionosphere waveguide. In the model, we investigate the ...

2019

EM Fields Generated by a Scale Model Helical Antenna and Its Use in Validating a Code for Lightning-Induced Voltage Calculation

Farhad Rachidi-Haeri

This paper aims at validating a code for the evaluation of lightning-induced overvoltages developed in the PSCADEMTDC environment using experimental results obtained on an experimental facility deployed at the University of S˜ao Paulo, Brazil that emulates ...

2019

Analysis of a bipolar upward lightning flash based on simultaneous records of currents and 380-km distant electric fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Amirhossein Mostajabi

In this paper, we present and discuss simultaneous records of current and wideband electric field waveforms at 380 km distance from the strike point associated with an upward bipolar flash initiated from the Säntis Tower. The flash contains 23 negative str ...

Elsevier2019