The effect of rain attenuation on orthogonally polarized LMDS systems in tropical rain regions

The effect of rainfall is to reduce the link reliability of local multipoint distribution service (LMDS) systems. We study the effects of rain attenuation on the microwave channel in two heavy rainfall tropical cites in Asia for wideband signals using a line-of-sight LMDS link with orthogonal polarizations. This is performed by transmitting signals with horizontal and vertical polarizations with carrier frequencies commonly used in LMDS systems. It is noted that the effect of depolarization due to rain is minimal at around 10 GHz; it is also observed that the rainfall rate has little effect on the difference in attenuation with different polarizations.