| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate contamination of the measurement value made at the SAR by Faraday Rotation which causes rotation of the plane of polarization of plane polarized radiation emitted by a radar e.g. a synthetic aperture radar and, even if returns polarized in orthogonal planes are measured at the synthetic aperture radar in order to determine polarimetric characteristics of the ground, which could show up features of the ground such as crop patterns. SOLUTION: In the invention, the transmitted plane polarized beam is pre- rotated in transmitter 9, the radar returns in receiver 13 are mathematically adjusted in signal formatting 14 and 15 to compensate for just the pre-rotated angle, to produce data streams on downlink 16 uncontaminated by the Faraday Rotation. The Farday Rotation may be estimated by external means 11 and 12, or by performing correlation 10 of the orthogonally polarized radar returns to establish a minimum, while the pre-rotation angle and mathematical correction of the returns are being iteratively adjusted, at which Faraday Rotation is assumed to be compensated.</p> |
