The indoor radio propagations’ multipath components (MPCs) of the THz band has a richscattered and reected rays due to the roughness material of the einvironment.Therefore theTerahertz channel model must have information of Angle of Arrival (AoA)/ Angle of Departure(AoD), and Time of Arrival (ToA). The further purpose of understanding the angle informationis to provide the optimal beam steering or beamforming algorithms. The AoA and AoD dependson the geometry of the environment in the room, due to some objects such as table, screen, andother furniture. Then we model those scattered AoA and AoD with respect to the directionof specular reection.
As depicted in the gure 3.10 the specular reection ray goes to eachsurface, wall, ceiling due to the compensation of the rough surface. The clusters due to the3.4.
SPATIAL MODELING OF SPECULAR AND SCATTERED MULTIPATH COMPONENT OF CHANNEL23MPCs appear around the specular reection point as mentioned before.Figure 3.11: First reection only of relative received power over AoA (upper) and AoD (lower)in the azimuth (?) and elevation () planeFigure 3.11 shows the clusters due to rst and second order reection scenario of MPCs. The24 CHAPTER 3. CHANNEL PROPAGATION MODEL OF THZ COMMUNICATIONreceived power in the clusters respect to the angles, AoA/AoD is shown in gure 3.
11, wherethe MPCs is gathered in the azimuth range of ? = 100? and 350? and elevation range of = 30?and 80? for AoA. The clustering also occurs in the DoA condition, and there is no correlationbetween AoA and AoD in this simulation. AoD refers to the transmitter (TX) site spread outwider than the AoA due to the specular reection direction to every point of the surface whichare close to the TX.3.
4.2 Angular Clustering ModelClustering which has been mentioned in the previous section is consequently as a group ofmultipath components (MPCs) which have a similar angle of arrival (AoA), angle of departure(AoD), and delays as depicted in gure 3.12 and 3.13. According to the AoA and AoD clusteringabove, the line of sight (LoS) condition can be seen by having the highest relative received power,as shown in black point both in AoD and AoA.
The Cluster due to the geometrical model by ray tracing method has been presented as thespread of angles and delay between transmitter and receiver with the surface roughness in theenvironment of the designed room as mentioned above.Figure 3.12: Angular Power Prole at receiver in azimuth plane3.
4. SPATIAL MODELING OF SPECULAR AND SCATTERED MULTIPATH COMPONENT OF CHANNEL253.4.3 Angular Power ProleThe specularly reected rays are clearly shown in gure 3.13 and 3.14 as the angular powerprole (APP) based on relative received power to the transmit power over the azimuth P(?) andelevation plane P() respectively at the receiver (RX) site.
The specular reection componentshave the dominant rays for each cluster with the scattered MPCs around each them. It is worthmentioning that the relative received power of scattered rays decay for the larger neither azimuthangle and elevation angle. As mentioned in the “AoA, AoD,and ToA” work, we also proposeto approach for each cluster of the angular power prole (APP) asFigure 3.13: Angular Power Prole at receiver in elevation planeP(?; ) = Pi(?; )cluster (3:14)For simplicity, the APP of each cluster P(?; ) has no correlation between the APP in azimuthplane and elevation plane, as