Error Propagation and Data Quality Assessment for ASAR Persistent Scatterer Interferometry

Abstract:
Quality control for Persistent Scatterer Interferometry (PSI) is currently still sub-optimal. This is a consequence of the fact that the estimated integer phase ambiguities are usually considered to be error-free, and of the underrated influence of the network of arcs between detected persistent scatterers. Internal error propagation in the network is in principle possible, and the choice of the reference point is arbitrary as long as covariances are taken into account. To test the influence of phase ambiguity estimation and network strength, a controlled experiment is performed using corner reflectors and varying network structures. It is shown that the quality of PSI results can be significantly degraded by incorrect estimation of the phase ambiguities and sub-optimal network design.