Improvement of the multi-temporal InSAR method using reliable arc solutions

ABSTRACT

In the multi-temporal interferometric synthetic aperture radar (MT-InSAR) technique, a deformation map is obtained through the integration of arc solutions. The reliability of the arc solutions directly influences the accuracy of the final deformation results. In this study, the influence of phase ambiguity on the arc solutions is analysed, and two indicators are proposed to identify the arcs with phase ambiguity. Precise variance–covariance estimation is implemented using the high-quality arcs, which are selected using four proposed indicators. The lambda method is used to perform phase unwrapping, and the low-quality arcs are removed according to the conditions of the indicators. In addition, the network is reconstructed based on a network search strategy to link as many coherent points as possible. Our improved MT-InSAR method is tested by processing 35 repeat COSMO-SkyMed (COnstellation of small Satellites for the Mediterranean basin Observation) SAR images covering Shanghai.

Acknowledgements

We greatly appreciate the constructive suggestions and comments from the anonymous reviewers. This research was supported by the State Key Development Program for Basic Research of China (No. 2013CB733304) and the National Science Foundation (No. 41674003). We thank the Beijing Vastitude Technology Co., Ltd. for providing the COSMO-SkyMed images.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the State Key Development Program for Basic Research of China [2013CB733304];the National Science Foundation [No. 41674003].