ds for lossy the Gabor frame decompositions. This procedure is fully dielectric wedges over just using the plane wave Fresnel equivalent to the decomposition of antenna fields into reflection coefficients. plane or cylindrical waves. The expressions for reflection Another [TrLC04] deals with the implementation of of a Gaussian beam on a plane boundary is then derived, curved surfaces in classical 3D RT programs. The most and applied to computations of indoor channels at mm difficult part is not SO much the electromagnetic treat- wave frequencies (57-59 GHz). Indeed at those fre- ment of the diffraction, but to find a fast way to de- quencies, the diffractions are negligible and hence no termine the reflection point of a wave on this curved diffraction is taken into account. Measurements in surface, in this case a cylinder. An iteration process con- a small laboratory confirm the validity of the procedure, verging in all special cases within six steps within an ac- even if only the dominant path is predicted accurately. curacy of 0.1% of the transmitter-receiver distance. Paper [RoMGPJL04] deals with a solution for multiple Geometrical optics (GO) models edge diffraction with a spherical incident wave for an- Many papers are treating this subject and provide appli- tenna location above, level and below the knife edge cations in the world of (mobile) communications. Some plane. The results are in good agreement with the Xia- just use Uniform Theory of Diffraction (UTD)/PO for Bertoni results, while requiring much less computer time, further investigations, which will be described in more and are accurate within at most 2.27 dB. A general pro- detail in Section 4.7.3, but some do provide treatments gram using a full 3D GTD theory, but tuned to MIMO of specific wave phenomena like diffraction and will be analysis, is described in [GaHS03]. Here, the efficiency is discussed here. Paper [GLBM02] uses GO to compute increased by simplifying the geometry to a discrete the effects of wind turbines on communication and safe