AUT Journal of Modeling and Simulation

AUT Journal of Modeling and Simulation

AN Improved UTD Based Model For The Multiple Building Diffraction Of Plane Waves In Urban Environments By Using Higher Order Diffraction Coeficients

Document Type : Research Article

Authors
A. Tajvidyi 1
A. Ghorbanii 2
M. Nasermoghaddasi 3
1 Corresponding Author, A. Tajvidy is with the Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 A. Ghorbani is with the Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran (e-mail: ghorbani@aut.ac.ir).
3 M. Nasermoghaddasi is with the Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran (e-mail: mn.moghaddasi@srbiau.ac.ir).
10.22060/miscj.2012.121
Abstract
This paper describes an improved model for multiple building diffraction modeling based on the uniform theory of diffraction (UTD). A well-known problem in conventional uniform theory of diffraction (CUTD) is multiple-edge transition zone diffraction. Here, higher order diffracted fields are used in order to improve the result; hence, we use higher order diffraction coefficients to improve a hybrid physical optics (PO)-CUTD model, the results show that the new model corrects errors of the PO-CUTD model. Therefore, the proposed model can find application in the development of theoretical models to predict more realistic path loss in urban environments when multiple-building diffraction is considered.
Keywords
Higher order diffraction coefficient
Multiple-edge Diffraction
UTD
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AUT Journal of Modeling and Simulation
Volume 44, Issue 2 - Serial Number 2
November 2012
Pages 11-17