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Application of Ray-Tracing Techniques to Mobile Localization
Published in Chao Gao, Guorong Zhao, Hassen Fourati, Cooperative Localization and Navigation, 2019
Francisco Saez de Adana, Oscar Gutiérrez Blanco, Josefa Gómez Pérez, Abdelhamid Tayebi, José Manuel Gómez Pulido, Antonio del Corte Valiente
Highly accurate ray-tracing analyses using three-dimensional terrain data have been carried out. In these studies, the terminals are accurately positioned using site-specific information for the measurement area. The ray-tracing model that can be obtained is a fully three-dimensional uniform theory of diffraction (UTD) model which includes ray-tracing acceleration techniques for improving the efficiency of the approach [9]. Being a ray-tracing model, the electric field levels can be obtained using the direct, reflected, transmitted, and diffracted fields. Thus, taking into account this variety of effects, the code provides good predictions [9]. These results can be used to examine the effect of varying certain sensing parameters on the precision of the system. The examined parameters include the number of antennas, the position of the antennas, and the number of tracks.
Design and Measurements Process of Wearable Communication, Medical and IOT Systems
Published in Albert Sabban, Wearable Systems and Antennas Technologies for 5G, IOT and Medical Systems, 2020
HFSS SBR+SBR.Physical Optics.Physical Theory of Diffraction (PTD).Uniform Theory of Diffraction (UTD).Creeping Wave.
EMI and EMC Control, Case Studies, EMC Prediction Techniques, and Computational Electromagnetic Modeling
Published in David A. Weston, Electromagnetic Compatibility, 2017
The uniform theory of diffraction (UTD) is an extension of the geometric theory of diffraction (GTD). Both of these techniques are high-frequency methods. They are accurate only when the dimensions of objects being analyzed are large relative to the wavelength of the field. In general, as the wavelengths of an electromagnetic excitation approach zero, the fields can be determined using geometric optics. UTD and GTD are extensions of geometric optics that include the effects of diffraction.
Efficient ray-tracing procedure for radio wave propagation modeling using homogeneous geometric algebra
Published in Electromagnetics, 2020
Ahmad H. Eid, Heba Y. Soliman, Sherif M. Abuelenin
RT algorithms model electromagnetic wave propagation by assuming that the waves propagate in straight lines in the form of rays (Ozgun 2016; Sevgi 2014; Yun and Iskander 2015). The classical geometric optics (GO) (Kline 1962) approach describes incidence, transmission and reflection (Ozgun 2016). To include diffraction effects, the uniform theory of diffraction (UTD) (Kouyoumjian and Pathak 1974) is used. The UTD extends Keller’s geometrical theory of diffraction (GTD) (Keller 1962) to provide smooth wave behavior along the shadow boundaries. In GO, rays are reflected from the illuminated (or lit) surfaces of the environment, i.e. surfaces that are visible to the considered electromagnetic source with no obstructions. Using the image method, reflections of an original (primary) source on illuminated surfaces serve as secondary sources or images. After finding all the rays arriving from the transmitter to the receiver (Thiel and Sarabandi 2009) the total field at a receiver location is determined by vector summing the direct field and the reflected fields emanating from the image sources. E.g. if a direct and one reflected ray reach the receiver, then the total received electric field is given by (1).
Scattering of waves by a planar junction between resistive half-screen and perfectly electric conducting wedge
Published in Journal of Modern Optics, 2018
The aim of this paper is to obtain the diffracted fields by a planar junction between resistive half-screen and PEC wedge. To our knowledge, this problem has not been investigated yet in the literature. As a first step, the relation between the scattered geometrical optics (GO) and diffracted waves by a PEC wedge will be put forward. Then the scattered GO fields of the problem, under consideration, will be evaluated. The diffracted waves by the junction will be obtained by using a relation between the scattered GO and diffracted fields. The uniform diffracted waves will be constructed with the uniform theory of diffraction (UTD) (22,23). The behaviour of the fields will be investigated numerically.