An advanced field prediction model including diffuse scattering

Ray tracing (RT) models are now widely adopted for field prediction in urban environment. Nevertheless, conventional RT tools still suffer for excessive central processing unit (CPU) time and inaccuracy in wide-band prediction. By increasing the maximum number of successive interactions (reflections, diffractions) little improvement in wide-band results can be usually achieved while CPU time increases exponentially. In the present paper, it is shown that by integrating reflection/diffraction with diffuse scattering, good narrow-band and wide-band results can be obtained with a low number of interactions. The adopted scattering model is a simple ray-based model, which has been embedded in a three-dimensional (3-D) RT program. The impact of diffuse scattering on narrowband and wide-band parameters is analyzed in the paper and the complete model is compared with measurements in a variety of cases, showing the validity of the approach.

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