Radar propagation at low altitudes

A review of the physics of radio wave propagation at low altitudes over various types of terrain is presented, with consideration for frequencies ranging from VHF to millimeter waves. Particular note is taken of propagation phenomena which affect detection of aircraft flying at low altitudes. Refraction, diffraction, absorption, and reflection effects are discussed, and several numerical models are presented for describing the phenomena. The material explored has applications in telecommunication and television coverage prediction, microwave link design, mobile radio communication, and the prediction of radar performance.