A Network Optimized Ridge Estimator for Robust PSI Parameter Estimation and Its Application on Deformation Monitoring of Urban Area

Persistent scatterer (PS) interferometry (PSI) has the ability to achieve submeter-scale digital elevation model and millimeter-scale deformation. However, it is difficult maintain good performance under long baseline large phase gradient. In this article, we develop a network optimized ridge estimator for two-tier PSI. Such method can increase parameter estimation robustness spatial continuity in single-prime mode urban build environments. First, construct an first-tier by outlier detection subsets construction. On basis, utilize as substitute weighted least squares (WLS) improve accuracy adjustment. second-tier network, detect remaining PSs constructing local star networks, thus increasing density of measurements network. The effectiveness proposed demonstrated using 2016–2018 TerraSAR-X dataset acquired Shenzhen Metropolis, China. addition, stress deformation two typical buildings, i.e., CITIC Building Convention Exhibition Center, are monitored analyzed.