Medium and high orbit SAR satellite distance ambiguity determination method based on reflector antenna

Abstract

The invention relates to a medium and high orbit SAR satellite range ambiguity determination method based on a reflector antenna. The method comprises the following steps: calculating an included angle theta BFP between a range direction one-dimensional directional diagram profile and a zero Doppler plane; taking a straight line from a satellite to the earth center as a reference line, and calculating a pitch angle zeta e0 and an azimuth angle zeta a0 of a beam center line of an SAR antenna pattern deviating from the reference line, a pitch angle zeta et and an azimuth angle zeta at of an imaging target point at any position in an imaging breadth, and a pitch angle zeta em and an azimuth angle zeta am of a distance ambiguity point; according to the pitch angles zeta e0, zeta et and zeta em and the azimuth angles zeta a0, zeta at and zeta am, calculating a two-way antenna pattern Geat of an imaging target point and a two-way antenna pattern Geam of a fuzzy point; and calculating the range ambiguity of any target according to the two-way antenna directional diagrams Geat and Geam, the incident angle of the imaging target point and the incident angle of the ambiguity point. According to the method, the calculation accuracy of the range ambiguity is greatly improved, and the related method can be suitable for medium and high orbit SAR satellites.

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