Energy inhibiting system for azimuth first fuzzy region echo signal of space-borne synthetic aperture radar (SAR)

Abstract

The invention discloses an energy inhibiting system for an azimuth first fuzzy region echo signal of a space-borne synthetic aperture radar (SAR). The energy inhibiting system runs in an SAR signal processor; and the raw echo of the SAR is processed in the SAR signal processor, the energy of the azimuth first fuzzy region echo signal is eliminated, and a residue signal is imaged, so that a non-fuzzy imaging result is obtained. In the system, the relevance between a first fuzzy region echo signal and raw echo data is utilized, the scattering coefficient of a first azimuth fuzzy region is resolved on the basis of a least square method, and an echo signal rebuilt by using the first fuzzy region scattering coefficient is eliminated from an acquired echo signal, so that a non-fuzzy main echo signal is obtained. As proved by simulation and imaging of a point target and a face target of a typical space-borne SAR parameter, the energy inhibiting system designed in the invention can be suitable for any space-borne SAR system.

Description

technical field [0001] The present invention relates to a processing system for echo signals of synthetic aperture radar, more particularly, it refers to an azimuth ambiguity suppression system for image processing of spaceborne synthetic aperture radar. Background technique [0002] Synthetic Aperture Radar (SAR) system is an active remote sensing device, which actively transmits electromagnetic waves to the target, and uses the echo signal received by the target scattering characteristics for imaging. Spaceborne SAR is a very complex system with many system parameters that are interrelated and restrict each other. In the range direction, the radar transmits a chirp signal, and performs pulse compression on the echo signal to obtain a higher resolution in the range direction; in the azimuth direction, the radar platform of the satellite changes the relative position of the beam and the target during the advancing process, forming Equivalent linear array antenna, thus impro...

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Problems solved by technology

The azimuth LFM signal is weighted by the azimuth antenna pattern, but the antenna pattern has side lobes and is in a higher frequency band

[0004] "Radar Imaging Technology" published by Harbin Institute of Technology Press and edited by Liu Yongtan in October 1999 pointed out that the Doppler spectrum of synthetic aperture radar is non-band-limited, and the target echo spectrum is repeated at the pulse repetition frequency. Echo signals will fold into the main spectral region, causing azimuth ambiguity

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