Open AccessThis article is
- freely available
A Phase-Offset Estimation Method for InSAR DEM Generation Based on Phase-Offset Functions
National Institute for Space Research (INPE), São José dos Campos, 12227-010 SP, Brazil
Orbisat da Amazônia S. A (ORBISAT), São José dos Campos, 12244-000 SP, Brazil
* Author to whom correspondence should be addressed.
Received: 9 January 2012; in revised form: 5 March 2012 / Accepted: 6 March 2012 / Published: 20 March 2012
Abstract: This paper presents a novel method for estimating the absolute phase offset in interferometric synthetic aperture radar (SAR) measurements for digital elevation model (DEM) generation. The method is based on “phase-offset functions (POF),” relating phase offset to topographic height, and are computed for two different overlapping interferometric data acquisitions performed with considerably different incidence angles over the same area of interest. For the purpose of extended mapping, opposite viewing directions are preferred. The two “phase-offset functions” are then linearly combined, yielding a “combined phase-offset function (CPOF)”. The intersection point of several straight lines (CPOFs), corresponding to different points in the overlap area allows for solving the phase offset for both acquisitions. Aiming at increasing performance and stability, this intersection point is found by means of averaging many points and applying principal component analysis. The method is validated against traditional phase offset estimation with corner reflectors (CR) using real OrbiSAR-1 data in X- and P-band.
Keywords: SAR Interferometry; phase offset estimation; absolute phase; DEM
Citations to this Article
Cite This Article
MDPI and ACS Style
Mura, J.C.; Pinheiro, M.; Rosa, R.; Moreira, J.R. A Phase-Offset Estimation Method for InSAR DEM Generation Based on Phase-Offset Functions. Remote Sens. 2012, 4, 745-761.
Mura JC, Pinheiro M, Rosa R, Moreira JR. A Phase-Offset Estimation Method for InSAR DEM Generation Based on Phase-Offset Functions. Remote Sensing. 2012; 4(3):745-761.
Mura, José Claudio; Pinheiro, Muriel; Rosa, Rafael; Moreira, João Roberto. 2012. "A Phase-Offset Estimation Method for InSAR DEM Generation Based on Phase-Offset Functions." Remote Sens. 4, no. 3: 745-761.