Changes
/* Conventional Physical Optics (GO-PO) */
where it is assumed that both the incident electric field and incident magnetic field have been decomposed into two parallel and perpendicular polarizations and Γ<sub>||</sub> and Γ<sub>⊥</sub> denote the reflection coefficients at the interface between air and the impedance surface for the cases of parallel and perpendicular polarizations, respectively. These reflection coefficients are given by:
:<math> R_{\|} = \frac{Z_0\eta_0\cos\theta - Z_s} {Z_0\eta_0\cos\theta + Z_s} </math>
:<math> R_{\perp} = \frac{Z_s\cos\theta - Z_0\eta_0} {Z_s\cos\theta + Z_0\eta_0} </math>
where <math>\eta_0 = 120\pi \; \Omega</math> is the intrinsic impedance of the free space.
:<math> \mathbf{J(r)} = \frac{2\eta_0}{\eta_0 + Z} \mathbf{\hat{n} \times H(r)} </math>
