engleski

Assessment of Giovaneli's Contribution to a Multiple Diffraction Losses Prediction

The simplest model for the prediction of diffraction losses in radio communications is based upon application of Fresnel’s diffraction theory. Diffraction losses are defined by multiple Fresnel integral which, except in the case of two obstacles, may be solved by numerical method acc. to Vogler. This method requires a computer application. However, widely accepted approximate methods are using procedures for reduction on equivalent number of single diffractions. The well known is procedures according to Bullington, Epstein-Peterson and Deygout, with certain improvements (Japanese method and Giovaneli˘s model). Taking into consideration computed results of diffraction losses calculated by Vogler’s numerical method, as reference one, it is evident that approximate Deygout's model gives the best results. However, with certain configuration of diffraction obstacles on radio path, Deygout's result may be considerably improved by introduction of Giovaneli˘s correction. The intention of this work is to give an improvement assessment of results obtained by application of Giovaneli˘s correction as the function of geometric disposition of diffraction obstacles.

Multiple diffraction; Giovaneli's model; Deygout's model

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