Abstract:

In the airborne synthetic aperture radar (SAR) system, the echo with low signaltoclutternoise ratio (SCNR) is caused by the beam pointing deviation, partial aperture effect, and the internal system increased noise. A new method of recursive variational diagonal loading is presented to improve the performance of suppressing the clutter and noise. The conventional imaging method often requires the high correlation for radar returns, which is fail at the low SCNR level.  By the recursive variational diagonal loading at the continuous subaperture echo after range compression, the clutter and noise are suppressed, and the information of target have been maintained and sufficiently protected. The quality of image is improved by selffocusing processing at lowSCNR condition. The results of the raw data have proved the validity of the proposed method.