caa a22 4500 528783157 20200430031142.0 cr unu---uuuuu 180924e201807 xx s 000 0 eng 10.3929/ethz-b-000280017 doi 10.3390/rs10071014 doi (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/280017 SAR tomography as an add-On to PSI: Detection of coherent scatterers in the presence of phase instabilities [Elektronische Daten] [Muhammad Adnan Siddique, id_orcid 0000-0003-1695-7694, Urs Wegmüller, Irena Hajnsek, Othmar; id_orcid 0000-0003-1795-6087 Frey] Remote sens. Open access ethresearch The estimation of deformation parameters using persistent scatterer interferometry (PSI) is limited to single dominant coherent scatterers. As such, it rejects layovers wherein multiple scatterers are interfering in the same range-azimuth resolution cell. Differential synthetic aperture radar (SAR) tomography can improve deformation sampling as it has the ability to resolve layovers by separating the interfering scatterers. In this way, both PSI and tomography inevitably require a means to detect coherent scatterers, i.e., to perform hypothesis testing to decide whether a given candidate scatterer is coherent. This paper reports the application of a detection strategy in the context of "tomography as an add-on to PSI”. As the performance of a detector is typically linked to the statistical description of the underlying mathematical model, we investigate how the statistics of the phase instabilities in the PSI analysis are carried forward to the subsequent tomographic analysis. While phase instabilities in PSI are generally modeled as an additive noise term in the interferometric phase model, their impact in SAR tomography manifests as a multiplicative disturbance. The detection strategy proposed in this paper allows extending the same quality considerations as used in the prior PSI processing (in terms of the dispersion of the residual phase) to the subsequent tomographic analysis. In particular, the hypothesis testing for the detection of coherent scatterers is implemented such that the expected probability of false alarm is consistent between PSI and tomography. The investigation is supported with empirical analyses on an interferometric data stack comprising 50 TerraSAR-X acquisitions in stripmap mode, over the city of Barcelona, Spain, from 2007-2012. Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0 ethresearch synthetic aperture radar (SAR) ethresearch SAR tomography ethresearch Deformation monitoring ethresearch Persistent scatterer interferometry (PSI) ethresearch urban deformation monitoring ethresearch Radar interferometry ethresearch displacement mapping ethresearch Spaceborne SAR ethresearch Differential interferometry ethresearch differential tomography ethresearch Siddique Muhammad Adnan joint author id_orcid 0000-0003-1695-7694 joint author Wegmüller Urs joint author Hajnsek Irena joint author Frey Othmar; id_orcid 0000-0003-1795-6087 joint author Remote Sensing Basel : MDPI 10 (7), p. 1014 2072-4292 http://hdl.handle.net/20.500.11850/280017 text/html WWW-Backlink auf das Repository (Open access) 1 Journal Article ethresearch ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/280017 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 700 1- Siddique Muhammad Adnan joint author ETHRESEARCH 700 -- id_orcid 0000-0003-1695-7694 joint author ETHRESEARCH 700 1- Wegmüller Urs joint author ETHRESEARCH 700 1- Hajnsek Irena joint author ETHRESEARCH 700 1- Frey Othmar; id_orcid 0000-0003-1795-6087 joint author ETHRESEARCH 773 0- Remote Sensing Basel : MDPI 10 (7), p. 1014 2072-4292 BK010053 XK010053 XK010000 ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access