Authors:
Chenxi Tian
and
Guoman Huang
Affiliation:
Chinese Academy of Surveying and Mapping, Haidian District, Beijing, China
Keyword(s):
Interferometric Synthetic Aperture Radar (InSAR), Single-Baseline (SB), Multi-Baseline (MB), Phase Unwrapping (PU).
Abstract:
The precision of phase unwrapping (PU), one of the primary methods used in interferometric synthetic aperture radar (InSAR), has a direct impact on the accuracy of the digital elevation model (DEM) that InSAR produces. The phase continuity assumption restricts single-baseline (SB) PU, and it is frequently hard to achieve optimal PU results in complex terrain areas with significant gradient variations. Fortunately, by utilizing numerous InSAR interferograms, or the elevation changes corresponding to each interference fringe in the interferogram, multi-baseline (MB) PU can totally overcome the restriction of the phase continuity assumption. Therefore, this paper proposes a virtual-baseline (VB) PU based on the two-stage programming (TSPA) MB PU approach to transform the SB PU problem into a MB PU problem. The novel method can be referred to as VB-TSPA. First, the effect of baseline length on MB PU is comprehensively considered to determine the virtual baseline length. Then a correspond
ing interferogram is simulated according to the length. Finally, the TSPA method is used for the MB PU. The experimental results from simulated and real data demonstrate that the novel PU method has a better effect than the traditional SB PU algorithm and can obtain higher precision DEM.
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