Two intersecting planes, P_e,s and P_e,r, form a wedge located on the longitudinal z-axis of a cylindrical coordinate system, extending from z₁ to z₂, (±∞ for an infinite wedge). Source (blue cross) and receiver (red circle) are located in the planes P_s and P_r (grey) at angles θ_s and θ_r, with all azimuth angles referenced to P_e,s. The shortest path between source and receiver intersects the edge at an angle φ at apex point z_a. The exterior wedge angle is referred to as θ_w. ISB and RSB denote the incident shadow and reflection shadow boundary, respectively.