Title:
宇宙機器搭載用レーダ
Document Type and Number:
Japanese Patent JP4750261
Kind Code:
B2
Abstract:
Faraday Rotation causes rotation of the plane of polarisation of plane polarised radiation emitted by a radar e.g. a synthetic aperture radar and, if returns polarised 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, the measurements made at the SAR are contaminated by the Faraday Rotation. In the invention, the transmitted plane polarised beam is pre-rotated in transmitter 9, the radar returns in receiver 13 are mathematically adjusted in signal formatting 14, 15 to compensate for just the pre-rotated angle, to produce data streams on downlink 16 uncontaminated by the Faraday Rotation. The Faraday Rotation may be estimated by external means 11, 12, or by performing correlation 10 of the orthogonally polarised 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.
Inventors:
Ralph Anthony Cordey
Nigel Spencer Weedon
Charles David Hall
Paul Ian Phelps
Nigel Spencer Weedon
Charles David Hall
Paul Ian Phelps
Application Number:
JP2000331478A
Publication Date:
August 17, 2011
Filing Date:
September 25, 2000
Export Citation:
Assignee:
Astrium Limited
International Classes:
G01S13/90; G01S7/02; G01S7/03; G01S7/28; G01S7/282; G01S7/40
Domestic Patent References:
| JP5188145A | ||||
| JP53013333A |
Foreign References:
| US5313210 |
Other References:
Gail, W.B.,"Effect of Faraday rotation on polarimetric SAR",IEEE Transactions on Aerospace and Electronic Systems,1998年 1月,Vol.34, No.1,p.301-308
Attorney, Agent or Firm:
Minoru Nakamura
Fumiaki Otsuka
Sadao Kumakura
Shishido Kaichi
Hideto Takeuchi
Toshio Imajo
Nobuo Ogawa
Village shrine Atsuo
Takaki Nishijima
Atsushi Hakoda
Fumiaki Otsuka
Sadao Kumakura
Shishido Kaichi
Hideto Takeuchi
Toshio Imajo
Nobuo Ogawa
Village shrine Atsuo
Takaki Nishijima
Atsushi Hakoda