The echoes of the nadir and the range ambiguity point will degrade the quality of high-resolution wide mapping band satellite-based synthetic aperture radar (SAR) imaging, and the use of digital beam forming (DBF) can make the antenna directional map to form a null in the corresponding direction for suppression. It is difficult to implement the existing multi-zero-points DBF processing technology on the satellite. In order to engineer DBF-SAR imaging technology, this paper proposes a set of improved engineering-achievable real-time multi-zero DBF processing method in elevation, which weights the echo signals in real time, and solves the inverse line velocity matrix problem faced in the real-time multi-zero weight generation by using the LDLT decomposition iteration to inhibit the Nadir echoes and range ambiguity in order to increase the range of the wave-position selection. The effectiveness of this real-time processing scheme is verified by multi-point target simulation.
CUI Zekai
,
XIAO Dengjun
,
QIU Jinsong
. An improved on-satellite-processing real-time digital formation technique of multi-zero beams for satellite-based SAR in elevation[J]. Journal of University of Chinese Academy of Sciences, 2025
, 42(6)
: 781
-791
.
DOI: 10.7523/j.ucas.2024.013
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