General adaptive-neighborhood technique for improving synthetic aperture radar interferometric coherence estimation

Abstract

A new method for filtering the coherence map issued from synthetic aperture radar (SAR) interferometric data is presented. For each pixel of the interferogram, an adaptive neighborhood is determined by a region-growing technique driven by the information provided by the amplitude images. Then pixels in the derived adaptive neighborhood are complex averaged to yield the filtered value of the coherence, after a phase-compensation step is performed. An extension of the algorithm is proposed for polarimetric interferometric SAR images. The proposed method has been applied to both European Remote Sensing (ERS) satellite SAR images and airborne high-resolution polarimetric interferometric SAR images. Both subjective and objective performance analysis, including coherence edge detection, shows that the proposed method provides better results than the standard phase-compensated fixed multilook filter and the Lee adaptive coherence filter.

Smart Filtering of Interferometric Phases for Enhancing Building Reconstruction

“…For this reason interferometric amplitudes are used to specify filter weights, which are finally determined by utilizing a MonteCarlo scheme. Approaches on adaptive complex Multilooking motivated by coherence filtering are published by Ciuc et al 2002 andVasile et al 2004. Both start with a statistical analysis of SAR amplitude data, followed by a twostage region growing on the same data.…”

Towards an Urban Dem Generation With Satellite Sar Interferometry

“…In particular, adaptive algorithms making use of amplitude statistics to fuse pixels with the same features are here analyzed. The algorithm in (Vasile et al, 2004), connecting pixels with a region growing technique, and the one in (Deledalle et al, 2011), connecting also not consecutive pixels inside a search window, are tested. The need to employ adaptive methods is clear looking at Fig.…”

“…An example of Raw DEM over Berlin, processed with the region growing algorithm (Vasile et al, 2004), with a theoretical resolution of 2 meters, is shown in Fig. 12.…”

High Resolution SAR Interferometry: Influence of Local Topography in the Context of Glacier Monitoring

“…The proposed procedure consists in gathering only the pixels which belong to the same HR spatial feature and respect the "local stationarity" hypothesis [6]. Under the assumption that small homogeneous regions within the two intensity images correspond to ground areas with an homogeneous cover which should respect the stationarity hypothesis, the multi-resolution technique employed in this paper is the Amplitude-Driven-AdaptiveNeighborhood (ADAN) [3].…”

“…The next generation of SAR satellites should provide meter resolution images and fully polarimetric data, which will be very useful to detect different features and backscattering mechanisms and to improve the extraction of the geometric deterministic component of the interferometric phase by adaptive techniques [3]. The two main limitations of the glacier InSAR measurements are the temporal decorrelation and the need to separate the topographical fringes from the displacement fringes.…”