Fig. 1. Electromagnetic wave propagation model with LoS, reflected ray, and scattered ray between transmitter (Tx) and receiver (Rx)

Fig. 2. Relationship between reflection loss and incident angle of TE wave

Fig. 3. Basic geometry of scattering at a rough surface

Fig. 4. Roughness factor versus frequency at different incident angles. (a) Incident angle is 60°; (b) incident angle is 45°; (c) incident angle is 30°

Fig. 5. Ratio of specular reflection to total power of ideal conductor's rough surface

Fig. 6. Verification of reflection coefficient and scattering coefficient. (a) Relationship between reflection coefficient and incident angle at 350 GHz frequency; (b) relationship between reflection coefficient and frequency with incident angles of 25° and 60°; (c) relationship between scattering coefficient and scattering angle with incident angle of 30°

Fig. 7. Scene diagram of a simulated environment

Fig. 8. Channel capacities for different transmission powers, transmission distances, and power allocation strategies