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


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:

3 M. Nasermoghaddasi is with the Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran (e-mail:


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.


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