First and second order statistics of clear-air attenuation on 11 GHz terrestrial path

Received power level fluctuations are measured on the terrestrial microwave link operating in 11 GHz band. Clear-air propagation effects such as tropospheric multipath and defocusing are observed to cause fading events with occasional attenuation peaks exceeding 20 dB for 0.01% of time on the 50 km long path. First and second order statistics of clear-air attenuation fluctuations are obtained from the three year period of measured data and compared with simple statistical models.