| Popis: |
Phase and amplitude of simulated troposcatter signals have been computed as functions of time, using thin layers of randomly spaced point scatterers moving horizontally and uniformly, normal to the path. The layer heights and cross-wind speeds were chosen to agree with the atmospheric conditions known to exist in two radio experiments. Comparisons of the simulated and actual radio signals show good agreements in amplitude fading rate and average Doppler shift versus antenna pointing angle in one case when the scattering angular dependence used in the simulation matched the classical −11/3 power-law isotropic refractivity spectrum. In the other case, where slower fading was observed, an anisotropic model of the refractivity spectrum produced excellent agreement between the simulated and radio data. Knowledge of the cross-wind speed allowed the degree of anisotropy for the model to be evaluated. |
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