A Spaceborne SAR Array Element Distance Estimation Method Based on Ground Radar Data

It is one of the main tasks of the space situational awareness to estimate the structure of spaceborne synthetic aperture radar (SAR) satellite, especially the estimation of array element distance. Research on the estimation of spaceborne SAR array element distance of microstrip antenna is carried out in this paper, formulas are derived by using the radar cross section (RCS) data, while the influence of distance over the RCS "ring" is also stimulated and verified by electromagnetic simulation and measured data. The influence of both planer inclination and array inclination over RCS is analyzed. Centimeter level estimation accuracy is approached by attitude transformation based on the measured data of S and X band radars, and the estimation accuracy error is better than 5 % in the multiple tracks situation. The result of this paper is helpful for improving the ability of space situational awareness.