Multipath propagation study combining terrain diffraction and reflection

A multiple knife-edge attenuation formula is derived by combining diffraction and ground reflection. As an example, the attenuation by double knife edges with ground reflection is derived in detail and the attenuation by a flat-topped obstacle with slanted sides is also calculated. The attenuated fields are proven to be the combination of eight field components, and the number of multipath reflection rays can be reduced based on the location of the main reflection point defined by path parameters. The formulas have clear physical meanings and can be used for field strength prediction in both mobile and fixed communications.