Numerical simulation of oblique ionospheric heating by powerful radio waves

Abstract. In this paper, we investigate the ionospheric heating by oblique incidence of powerful high-frequency (HF) radio waves using three-dimensional numerical simulations. The ionospheric electron density and temperature perturbations are examined by incorporating the ionospheric electron transport equations and ray-tracing algorithm. The energy distribution of oblique incidence heating waves in the ionosphere is calculated by the three-dimensional ray-tracing algorithm. The calculation takes into consideration the electric field of heating waves in the caustic region by the plane wave spectral integral method. The simulation results show that the ionospheric electron density and temperature can be disturbed by oblique incidence of powerful radio waves, especially in the caustic region of heating waves. The oblique ionospheric heating with wave incidence parallel and perpendicular to the geomagnetic field in the mid-latitude ionosphere is explored by simulations, results of which indicate that the ionospheric modulation is more effective when the heating wave propagates along the magnetic field line. Ionospheric density and temperature striations in the caustic region due to thermal self-focusing instability are demonstrated, as well as the time evolution of the corresponding fluctuation spectra.

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The three-dimensional ionospheric electron density imaging in Japan using the approximate kalman filter algorithm

Journal of Atmospheric and Solar-Terrestrial Physics ◽

10.1016/j.jastp.2021.105628 ◽

2021 ◽

pp. 105628

Author(s):

Rui Song ◽

Katsumi Hattori ◽

Xuemin Zhang ◽

Chie Yoshino

Keyword(s):

Kalman Filter ◽

Electron Density ◽

Three Dimensional ◽

Ionospheric Electron Density ◽

Kalman Filter Algorithm

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Three‐Dimensional and Trans‐Hemispheric Changes in Ionospheric Electron Density Caused by the Great Solar Eclipse in North America on 21 August 2017

Geophysical Research Letters ◽

10.1029/2018gl080365 ◽

2018 ◽

Vol 45 (20) ◽

Cited By ~ 8

Author(s):

Liming He ◽

Kosuke Heki ◽

Lixin Wu

Keyword(s):

North America ◽

Electron Density ◽

Solar Eclipse ◽

Three Dimensional ◽

Ionospheric Electron Density

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ISS FPP Ionospheric Electron Density and Temperature Measurements - Results, Comparison with the IRI-90 Model, and Implications for ISS Charging

41st Aerospace Sciences Meeting and Exhibit ◽

10.2514/6.2003-1083 ◽

2003 ◽

Cited By ~ 5

Author(s):

Dale Ferguson ◽

Thomas Morton ◽

G. Hillard ◽

Robert Personen

Keyword(s):

Electron Density ◽

Temperature Measurements ◽

Ionospheric Electron Density ◽

Electron Density And Temperature

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Validation of Three-Dimensional Ray-Tracing Algorithm for Indoor Wireless Propagations

ISRN Communications and Networking ◽

10.5402/2011/324758 ◽

2011 ◽

Vol 2011 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Majdi Salem ◽

Mahamod Ismail ◽

Norbahiah Misran

Keyword(s):

Ray Tracing ◽

Electromagnetic Waves ◽

Three Dimensional ◽

Prediction Method ◽

Access Point ◽

Network Access ◽

Multiple Reflections ◽

Indoor Wireless ◽

3D Ray Tracing ◽

Tracing Algorithm

A 3D ray tracing simulator has been developed for indoor wireless networks. The simulator uses geometrical optics (GOs) to propagate the electromagnetic waves inside the buildings. The prediction technique takes into account multiple reflections and transmissions of the propagated waves. An interpolation prediction method (IPM) has been proposed to predict the propagated signal and to make the ray-tracing algorithm faster, accurate, and simple. The measurements have been achieved by using a single Wi-Fi network access point as a transmitter and a laptop as a receiver. Measured data had been collected at different positions in indoor environment and compared with predicted signals. The comparison of the predicted and measured received signals gave root mean square error of 2.96 dB and std. deviation of 2.98 dB.

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Ionospheric heating by powerful radio waves

Radio Science ◽

10.1029/rs009i011p01049 ◽

1974 ◽

Vol 9 (11) ◽

pp. 1049-1063 ◽

Cited By ~ 45

Author(s):

G. Meltz ◽

L. H. Holway ◽

N. M. Tomljanovich

Keyword(s):

Radio Waves ◽

Powerful Radio ◽

Ionospheric Heating

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The appearance of the objects rolling at relativistic speeds

Canadian Journal of Physics ◽

10.1139/p08-083 ◽

2008 ◽

Vol 86 (12) ◽

pp. 1437-1441 ◽

Cited By ~ 2

Author(s):

A Sfarti

Keyword(s):

Ray Tracing ◽

Three Dimensional ◽

Line Of Sight ◽

Rectilinear Motion ◽

Complex Type ◽

Computer Representation ◽

Tracing Algorithm ◽

Moving Bodies ◽

Circular Outline ◽

Relativistic Equations

In the late 1950s Terrell and Penrose produced a series of papers dealing with the appearance of the rapidly moving bodies while in rectilinear motion as photographed by a simple, pinhole camera. A few more articles on the same subject followed, for example, Penrose showed that a sphere is always seen having an exactly circular outline, at any velocity, at any distance and for any line of sight. In the present paper, we will deal with a more complex type of motion, the combination of translation and rotation that can be seen when observing the wheels of a vehicle passing by. Since Terrell and Penrose wrote their papers, great advances in the camera simulation via computer representation have been made. The field that deals with the simulation of realistic cameras via computers is called ray tracing. In the current paper, we will combine two different disciplines, relativistic physics and three-dimensional graphics to derive new results. Our paper is divided in two main parts, in the first half, we will derive the relativistic equations for rolling motion without slip and we will make some connections with the physical requirements of a relativistic ray-tracing algorithm. In the second half, we will review the foundations of classical ray-tracing algorithms and we will introduce the additional features for operation at relativistic speeds. We will demonstrate an interesting self-canceling effect of the relativistic Doppler shift on the colors wavelengths of the moving object.PACS No.: 03.30.+p

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POVScript+: a program for model and data visualization using persistence of vision ray-tracing

Journal of Applied Crystallography ◽

10.1107/s0021889803006721 ◽

2003 ◽

Vol 36 (3) ◽

pp. 944-947 ◽

Cited By ~ 247

Author(s):

T. D. Fenn ◽

D. Ringe ◽

G. A. Petsko

Keyword(s):

Structural Analysis ◽

Ray Tracing ◽

Electron Density ◽

Data Visualization ◽

Visual Information ◽

Three Dimensional ◽

Input Output ◽

High Quality ◽

Rank Tensor ◽

Volumetric Rendering

Macromolecular visualization is hampered by the fragmented set of available programs and the lack of cooperativity among them. The amount of visual information required for robust structural analysis is relatively difficult to generate and rarely allows further high-quality three-dimensional graphic rendering. Here, a modification ofMolScript[Kraulis (1991).J. Appl. Cryst.24, 946–950] is presented which contains the capability of the originalMolScript, the ability to carry out a majority of the options available in most other crystallographic visualization packages, as well as several new features of its own.POVScript+(currently version 1.62) allows anisotropic displacement ellipsoid rendering (read in as a second-rank tensor from a PDB file), electron-density polygonization (in several formats derived from a `marching tetrahedra' approach), volumetric rendering of electron density and GRASP/MSMS surface-map input/output. Finally,POVRayoutput is supported (viaa modified version ofPovScript) to generate high-quality renderings that are easily modified for any of a number of purposes (e.g.animations or altered textures).POVScript+provides a marked increase in the amount of structural and atomic detail possible, while still allowing a straightforward means of generating this information.

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Simulation of tree point cloud based on the ray-tracing algorithm and three-dimensional tree model

Biosystems Engineering ◽

10.1016/j.biosystemseng.2020.10.007 ◽

2020 ◽

Vol 200 ◽

pp. 259-271

Author(s):

Yaxin Li ◽

Pei Wang ◽

Jingqian Sun ◽

Xiaozheng Gan

Keyword(s):

Ray Tracing ◽

Point Cloud ◽

Three Dimensional ◽

Tree Model ◽

Tracing Algorithm

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Ionospheric precursors to scintillation activity

Annals of Geophysics ◽

10.4401/ag-6389 ◽

2014 ◽

Vol 57 (1) ◽

Author(s):

Paul S.J. Spencer

Keyword(s):

Electron Density ◽

Ionospheric Scintillation ◽

Small Scale ◽

Navigation Systems ◽

Radio Waves ◽

Ionospheric Electron Density ◽

Plasma Drift ◽

L Band ◽

Electron Density Irregularities ◽

Tomographic Inversions

Ionospheric scintillation is the rapid fluctuation of both phase and amplitude of trans-ionospheric radio waves due to small scale electron density irregularities in the ionosphere. Prediction of the occurrence of scintillation at L band frequencies is needed to mitigate the disruption of space-based communication and navigation systems. The purpose of this paper is to present a method of using tomographic inversions of the ionospheric electron density obtained from ground-based GPS data to infer the location and strength of the post-sunset plasma drift vortex. This vortex is related to the pre-reversal enhancement in the eastwards electric field which has been correlated to the subsequent occurrence of scintillation.

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