Statistical Predictions During Rain for Dual-Polarization Systems

Abstract

A theoretical formula is derived for the joint statistics of cross-polarization discrimination (XPD) and rain attenuation for a microwave link, assuming log-normal and normal forms for the rain attenuation and XPD distribution respectively. This formula is used to predict the distribution of XPO conditional on the co-polar rain attentuation, and also the distribution of XPD during a rain fade. Experimental results from Atlanta, Georgia and from Southern England are compared with theoretical curves, and the agreement is encouraging. Finally, a formula for the estimation of outage time on microwave links, appropriate to dual-polarization frequency-reuse systems has also been derived.