Physical Optics modeling of fixed microwave links with digital terrain data

A Physical Optics approach to the analysis of the electromagnetic propagation and the estimation of main link parameters in LOS, point-to-point microwave links operating within urban environments is proposed and discussed. The propagation geometry is modeled by a triangular mesh obtained from the transformation of digital terrain (LIDAR) data. An asymptotic Physical Optics approximation is subsequently employed in the calculation of the scattered field power from surfaces within the main beamwidth of the two antennas. Random realizations of reflected and scattered field constituents are superimposed to the direct field and predict with reasonable accuracy link performance for main design variables, such as antenna position, gain and height. Direct and scattered field calculations are compared with measurements of fixed links of variable distance at 40GHz.