RAIN DEPENDANT SITE DIVERSITY OUTAGE IMPROVEMENTS STATISTICS FOR SYSTEMS WORKING IN MILLIMETER-WAVE BAND

The signal propagation at the frequencies above 10 GHz suffers from significant attenuation due to rain, which in case of point-to-multipoint systems is unlikely to be compensated for by available fade margin alone. For this reason and especially thanks to the non-uniform spatial distribution of the rain rate, it is suitable to utilize site diversity concept during planning of point-to-multipoint wireless systems. A database of radar data for numerous types of rain events has been established to enable system testing under different conditions. Outage improvement was studied using space-time simulations of point-to-multipoint systems in a specific area under a specific rain conditions. System outage improvement probability was derived as a straightforward function of the rain fade margin, angle separation and distances of main and diversity hubs. Some of the simulation results at 42 GHz and corresponding outage improvement probability using the site diversity are presented as well