Potential of Topographic Measurement by Time-Series Loose Distributed SAR Interferometry

The development of distributed synthetic aperture radar interferometry (InSAR) brings further prospects for future Earth observation, especially for high-resolution topographic measurement. However, it is difficult and costly to control tight formation flying, so considering loose distributed InSAR is significant. Then, multiple phase error and atmospheric phase, which cannot be eliminated by loose formation flying and have non-stationary and non-Gaussian features, should be disposed properly to retrieve accurate digital elevation models (DEM). With respect to the foregoing, utilizing spatiotemporal joint estimation, a new DEM retrieval method based on the particle filter (PF) is proposed. It has been validated by simulation experiments that the proposed method is capable of retrieving high-accuracy and high-resolution topographic measurement even under non-stationary and non-Gaussian atmospheric phase and other multiple phase errors, proving the potential of high-quality topographic measurement in time-series loose distributed InSAR.