Digital Radiolaenk: Vagutbredningsmaetningar Oever en 13 GHz Frisikt-Foerbindelse (Digital Radio Link: Wave Propagation Investigations on a 13 GHz Line-of-Sight Path)

摘要

Propagation investigations on two high capacity (34 Mb/s) 13 GHz-paths (28 km and 46 km) were performed during the period 1983, 1984 and 1985. The main purpose of the measurements were to examine the activity of frequency selective fading and rain attenuation. The event-controlled measurements described where the power spectrum and signal levels are recorded in the case of a spectral slope or a fade depth exceeding a specific threshold. The suitable types of fading, such as rain- and Rayleigh-fading, are described with corresponding statistical models. A fit is made of the models to experimental cumulative distributions. A least-square fit is made of the reduced 3-way model to measured transfer functions. The resulting distribution of corresponding parameters of the model is presented together with the correlation between them. Finally, a model is proposed for the calculation of unavailability caused by rain, Rayleigh- and frequency selective fading.