Co-polarization Level Research Articles

A technique for improving depolarization measurements beyond 10 GHz: Tilting the polarization planes

Depolarization measurements in linear polarization aiming at determining the effective canting angle of the principal planes and the related anisotropy can be improved, in many important cases, by adopting the simple expedient of tilting the polarization planes with respect to the vertical/horizontal orientations. Optimum tilt angles depend on the system configuration but the choice is not critical in a range spanning from about <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">20\deg</tex> to about <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">30\deg</tex> provided that the disturbance is small enough (say 50 dB under the copolar level) and/or the anisotropy of the medium is large enough (say 2 dB in the differential attenuation).

Fluctuations on OTS-Earth copolar link against diurnal and seasonal variations

Measurements on the copolar level of the 11.575 GHz OTS-Earth link have been analysed during the year 1981, using a 1 s sampling time. The variation of the fluctuations amplitude is evaluated as a function of the time of day and of the month of the year. It is compared to the number of attenuation events over the same period and against the same parameters. The statistic of the number of occurrences is calculated as a function of the amplitude of the events.