Theoretical study of the effect of different types of tropical rainfall on microwave and millimeter-wave propagation
Article first published online: 7 DEC 2012
Copyright 1999 by the American Geophysical Union.
Volume 34, Issue 5, pages 1103–1124, September-October 1999
How to Cite
1999), Theoretical study of the effect of different types of tropical rainfall on microwave and millimeter-wave propagation, Radio Sci., 34(5), 1103–1124, doi:10.1029/1999RS900063., , and (
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 2 JUN 1999
- Manuscript Received: 7 DEC 1998
In this paper, the effects of tropical rainfall on the propagation of microwave and millimeter-wave signals on terrestrial paths have been investigated. Quantitative evaluation of spheroidal raindrop scattering parameters such as the scattering amplitude functions, total and scattering cross sections, and so on, were carried out for linear polarization (horizontal and vertical), using the least squares fitting method over the frequency range 1–100 GHz. Incident radio signals are assumed plane and arrive normally on the raindrop axis. For the purpose of application to slant paths, two other incident angles, 50° and 70°, were considered. The computed forward scattering amplitude functions were employed to compute the complex effective propagation constant of the radio signals in four tropical rainfall types: drizzle, widespread, shower, and thunderstorm. The corresponding specific attenuation and specific phase shift were computed. Specific attenuation and phase shift due to the rain types for circularly polarized radio signals were also derived. The parameters of the power law relationship between attenuation, phase shift, and rain rate were computed for each rain type and compared with existing temperate and tropical models. The problem of rain-induced depolarization was also investigated by computing the cross polarization discrimination for the four rainfall types over the frequency range 1-50 GHz, which is of immediate importance to system designers.