Analysis of ´unexpected´ depolarization effects of precipitation scatter signals at 30 GHz

Investigations of precipitation scattering at frequencies above 10 GHz have shown that the real extent of cochannel interference of the co-polar component can be underestimated considerably (up to 10 dB) by conventional measuring methods since some effects are not taken into account. This was previously proved theoretically and, inter alia, by measurements of the cumulative distribution of the transmission loss. An important consequence of this is that both the type and extent of the cochannel interference of the cross-polar component has to be assessed anew above 10 GHz, the more so as the polarization decoupling due to precipitation scattering is, on average, of the order of 10 dB. The present paper is therefore confined to two properties of the pure scattering signal: the form of the power density spectrum as a whole as well as the dynamic range of short-time fluctuations of the scattering power. In this context, the results of the cross-polar components are compared with those of the corresponding co-polar components.