e/below and sideways around the canopy, and diffuse scattering by the leaves. The vegetation effects are captured implicitly in the path loss equations. A stochastic method for capturing human and vehicular blocking in mmWave frequency regions can be used (among other methods) to model the blockage effect. In this case, the number of blockers must be first determined. For this purpose, multiple 2D angular block- ing regions, in terms of center angle, azimuth, and elevation angular span are generated around the UE. There is one self-blocking region and K = 4 non-self-blocking regions, where K may be changed for certain scenarios such as higher blocker density. Note that the self-blocking component of the model is important in capturing the effects of human body blocking. In the next step, the size and location of each blocker must be generated. For self- blocking, the blocking region in the UE local coordinate system4 is defined in terms of ele- vation and azimuth angles and azimuth and elevation angular span (xsb,Ysb) [4,5]. where the parameters of the above equation are described in Table 3.1. For non-self-blocking k = 1, 2, 3, 4, the blocking region in global coordinate system is defined as follows [4,5]: (0)(0 where d is the distance between the UE and the blocker; other parameters are given in Table 3.1. Global and local coordinate systems are used to locate geometric items in space. By default, a node coordi- nates are defined in the global Cartesian system. 298 Chapter 3 Table 3.1: Blocking region parameters [4,5]. Self-Blocking Region Parameters Portrait (degree) Landscape (degree) Blocking Region Parameters Blocker Index k = 1,2,3, 4 InH scenario Uniform in [0°, Uniform in [15°, Uniform in [5°,15°] UMi_x, Uma_x, RMa_x Uniform in [0°, Uniform in [5°,15°] scenarios The attenuation of each cluster due to self-blocking corresponding to the center angle pair (Osb,L'sb) is 30 dB provided that P'AOA - and - otherwise, the attenuation is 0 dB. Note that ZOA denotes the Zenith angle of arrival. The attenuation of 