Simulation Of Radio Wave Propagation Research Articles

Acceleration of Tensor Interpolation-Based Radio Map Estimation

The radio map of wireless communications should be surveyed in advance when installing base stations to efficiently utilize radio waves. Generally, this is calculated using radio wave propagation simulation. Because the simulation is time-consuming, a tensor-rank minimization-based interpolation method has been proposed as fast method. However, this method interpolates the radio map using an iterative algorithm. The number of iterations required for further acceleration should be reduced; therefore, we propose a tensor interpolation using rank minimization that considers the characteristics of radio wave propagation. Furthermore, we proved that the proposed method could interpolate with fewer iterations than the existing method.

Radio wave propagation simulation considering Doppler shift caused by other vehicles

Radio wave propagation simulation considering Doppler shift caused by other vehicles

Prediction of Fixing of RTK-GNSS Positioning in Multipath Environment Using Radiowave Propagation Simulation

Prediction of Fixing of RTK-GNSS Positioning in Multipath Environment Using Radiowave Propagation Simulation

ロボットの遭難を防ぐための電波伝搬シミュレーションによる環境構成材料推定の高精度化

We studied how to prevent a “distress of robot” by radio wave propagation simulation. When we conducted radio wave propagation simulation, we need to set material. We need to estimate the material because it is difficult to set material constituting the environment in advance in an unknown environment. In this paper, we evaluate about estimation method of material constituting environment.

1P1-M08 電波伝搬シミュレーションのための三次元地図生成に関する研究

When the tele-operated mobile robot went over its communication range accidentally, the operation would be suspended. We named this kind of trouble "the distress of mobile robot". In order to prevent the distress of mobile robot, it is necessary to estimate communications conditions around the robot by means of radio wave propagation simulation. We aim to prove radio wave propagation simulation is effective method to prevent "the distress of mobile robot" For the simulation, the environment model around the robot is needed, which consists from its shape and permittivity. In this paper, we describe about the 3D shape map generated from depth sensory data.

A Simulation System of Radio Propagation Effect Evaluation Based on GIS

Construction of wave propagation effects assessment simulation system based on GIS, for enhancing the capabilities of our military radio environment awareness, forecasting, warning and assessment of the effect is significant.In this paper, the original geographic data and radio wave propagation data will be unified as vector and raster data into GIS system structure based on ArcObjects components, combined with the development of visual language Visual C++ 6.0, designed and constructed to assess the effect of radio wave propagation simulation system. designed and built a radio wave propagation effects assessment simulation system. The system has data management, scene visualization, effects assessment, graphics output function modules, Achieved wave propagation effects assessment simulation and visualization presentation.

1P2-G06 遠隔操作ロボットのための電波伝搬推定における障害物の影響(サーチ&レスキューロボット・メカトロニクス(2))

When the tele-operated mobile robot went over its communication range accidentally, the operation would be suspended. We named this kind of trouble "the distress of mobile robot". In order to prevent the distress of mobile robot, it is necessary to estimate communications conditions around the robot by means of radio wave propagation simulation. It is thought that the robot by means of radio wave propagation simulation about the indoor environmental uses the model who settled a plan of building for the cause. However, plan of building may be different from true environment, because many building are given equipment, enlargements and rubble. They can obstacle to the robot and the communication. In this paper, we simulated radio wave propagation on some indoor environment models. We compared that results and considered that obstacle effects tele-operated mobile robot.

1P1-P16 移動ロボットによる動的な電波状況推定のための環境形状データの自動生成(サーチ&レスキューロボット・メカトロニクス)

When the tele-operated mobile robot went over its communication range accidentally, the operation would be suspended. We named this kind of trouble "the distress of mobile robot". In order to prevent the distress of mobile robot, it is necessary to estimate communications conditions around the robot by means of radio wave propagation simulation. In this paper, we describe the environmental map suitable to electromagnetic simulation.

PETOOL: MATLAB-based one-way and two-way split-step parabolic equation tool for radiowave propagation over variable terrain

A MATLAB-based one-way and two-way split-step parabolic equation software tool (PETOOL) has been developed with a user-friendly graphical user interface (GUI) for the analysis and visualization of radio-wave propagation over variable terrain and through homogeneous and inhomogeneous atmosphere. The tool has a unique feature over existing one-way parabolic equation (PE)-based codes, because it utilizes the two-way split-step parabolic equation (SSPE) approach with wide-angle propagator, which is a recursive forward–backward algorithm to incorporate both forward and backward waves into the solution in the presence of variable terrain. First, the formulation of the classical one-way SSPE and the relatively-novel two-way SSPE is presented, with particular emphasis on their capabilities and the limitations. Next, the structure and the GUI capabilities of the PETOOL software tool are discussed in detail. The calibration of PETOOL is performed and demonstrated via analytical comparisons and/or representative canonical tests performed against the Geometric Optic (GO) + Uniform Theory of Diffraction (UTD). The tool can be used for research and/or educational purposes to investigate the effects of a variety of user-defined terrain and range-dependent refractivity profiles in electromagnetic wave propagation. Program summary Program title: PETOOL (Parabolic Equation Toolbox) Catalogue identifier: AEJS_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEJS_v1_0.html Program obtainable from: CPC Program Library, Queenʼs University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 143 349 No. of bytes in distributed program, including test data, etc.: 23 280 251 Distribution format: tar.gz Programming language: MATLAB (MathWorks Inc.) 2010a. Partial Differential Toolbox and Curve Fitting Toolbox required Computer: PC Operating system: Windows XP and Vista Classification: 10 Nature of problem: Simulation of radio-wave propagation over variable terrain on the Earthʼs surface, and through homogeneous and inhomogeneous atmosphere. Solution method: The program implements one-way and two-way Split-Step Parabolic Equation (SSPE) algorithm, with wide-angle propagator. The SSPE is, in general, an initial-value problem starting from a reference range (typically from an antenna), and marching out in range by obtaining the field along the vertical direction at each range step, through the use of step-by-step Fourier transformations. The two-way algorithm incorporates the backward-propagating waves into the standard one-way SSPE by utilizing an iterative forward–backward scheme for modeling multipath effects over a staircase-approximated terrain. Unusual features: This is the first software package implementing a recursive forward–backward SSPE algorithm to account for the multipath effects during radio-wave propagation, and enabling the user to easily analyze and visualize the results of the two-way propagation with GUI capabilities. Running time: Problem dependent. Typically, it is about 1.5 ms (for conducting ground) and 4 ms (for lossy ground) per range step for a vertical field profile of vector length 1500, on Intel Core 2 Duo 1.6 GHz with 2 GB RAM under Windows Vista.

Simulation of radiowave propagation in hospitals based on FDTD and ray-optical methods

This paper addresses the simulation of radiowave propagation in hospitals in the frequency range from 42.6 MHz to 5.2 GHz. Due to the special construction of the walls, wave propagation in hospitals is different from other buildings. These walls contain metallic layers within their structure, e.g., operating rooms with CrNi-steel faced walls, X-ray rooms with lead shielded walls or magnetic resonance tomography rooms with an explicit EMC shielding made of copper. Wave propagation in such rooms has not been simulated yet. This work uses a simulation tool based on the finite-difference time-domain method that allows a detailed simulation of the walls, floors and ceilings for frequencies from 42.6 to 300 MHz. For higher frequencies up to 5.2 GHz a ray-optical simulation tool must be used and the walls must be modeled homogeneously by multiple layers of different materials. In order to accurately model the walls, the electromagnetic properties of the different material layers inside the walls have to be known. The results of extensive wave propagation measurements in four different hospitals are used for the determination of these parameters. This paper presents the methods used to obtain these material parameters and their performance in a ray-optical simulation tool.

Low-frequency radio wave propagation in the earth-ionosphere waveguide disturbed by a large-scale three-dimensional irregularity

In this paper, we develop further the analytical and numerical method of solving three-dimensional problems in the theory of radio wave propagation, including three-dimensional local inhomogeneities (ionospheric disturbances or Earth’s surface irregularities). To model the Earth-ionosphere waveguide, we use the surface impedance concept, by which the irregularity extending beyond one waveguide wall has an arbitrary smooth shape, and its surface can be described by the impedance. In the scalar approximation, this problem is reduced to a two-dimensional integral equation for the irregularity surface, which, by asymptotic (kr ≫ 1) integration over the coordinate transverse to the propagation path (with allowance for terms of the order of (kr)−1), is reduced to a one-dimensional integral equation, in which the integration contour is the linear contour of the irregularity. The equation is solved numerically, combining the inversion of a Volterra integral operator and successive approximations. By reducing the computer times, this method enables one to study both small-scale and large-scale irregularities. The results of numerical simulation of radio wave propagation in the presence of a powerful three-dimensional ionospheric disturbance are presented as an example.

The magnetotail: A rough and leaky plasma waveguide for terrestrial radio waves

A simulation of radio wave propagation is used to explain deep tail observations of the circumterrestrial radio sources. The large angular diameter of these sources and their large angular distance to Earth cannot be explained by simple reflections on the magnetopause. Waves must enter the inhomogeneous magnetosheath and this requires corrugations of the magnetopause. The angular diameter observations can be interpreted quantitatively. Some variations of the source apparent direction can also be interpreted as due to the rotation of a broad beam or to a change in the relatives intensities of two primary near‐Earth sources, but some others might require distorsions of the three‐dimensional shape of the tail or motions of that tail with respect to the observer.