Critical baseline analysis in GEO repeat pass InSAR

Compared with LEO SAR, the orbital altitude of GEO SAR is higher and the orbital eccentricity is larger, so the spatial decorrelation model of traditional LEO repeat pass InSAR can not be applicable for the GEO repeat pass InSAR. Considering the special problems of GEO repeat pass InSAR, a spatial decorrelation model is established which is applicable for the GEO repeat pass InSAR and the expressions of spatial decorrelation coefficient and the critical baseline are derived. Finally, the critical baseline in GEO repeat pass InSAR is simulated when J2 perturbation is considered.