Scattering of millimeter waves from acid rain

A theoretical investigation of scattering characteristics of millimeter wav es from acid rain is conducted using the method of vector spherical functio n expansion. The particles of acid rain are considered as the double-layere d spheroid. The method is used to derive an analytical solution to the prob lem of scattering of millimeter waves by a coated dielectric spheroid. The normalized bistatic cross section versus scattering angle for the acid rain drop is calculated at frequencies of 35GHz and 94GHz. This is the first par t of our study scattering characteristics of millimeter waves from acid rai n.