Abstract
The paper describes spectral measurements on a 20 GHz shallow-angle bistatic scatter link using antennas directed off-axis in the vertical plane. This configuration retains the property of a line-of-sight microwave link of that the Doppler and vibration spectra being separated. Theoretical Doppler and vibration spectra are presented. In some cases the observed Doppler spectra agree with theory, and show qualitatively the expected shifts associated with drop size distribution variations. Other interesting spectra show unexpectedly high Doppler frequencies, suggesting that downdraughts are being observed. In some cases a high frequency tail on the spectra is regarded as a possible, though not conclusive, detection of the vibration component.
Analyse
Description de cette liaison utilisant des antennes faiblement dépointées verticalement et permettant de séparer le spectre de puissance Doppler et le spectre des vibrations des gouttes. Un spectre théorique calculé pour des gouttes sphériques tombant verticalement, est comparé à d’autres spectres Doppler obtenus expérimentalement. On étudie les différences entre ces deux spectres correspondant, dans certains cas, aux variations des dimensions des gouttes de pluie sans qu’il soit possible de conclure définitivement.
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Haworth, D.P., McEwan, N.J. Spectral analysis of the received signal on a 20 GHz bistatic scatter link. Ann. Télécommunic. 35, 390–397 (1980). https://doi.org/10.1007/BF03003517
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DOI: https://doi.org/10.1007/BF03003517