Title
Coherence Improvement Of Cross-Interferometric Pair By A Block Azimuth Filtering
Abstract
ERS-ENVISAT cross-interferometry with a small height ambiguity is useful to measure the topography in the regions of low slope. Azimuth common-band filtering is a key pre-processing for the cross-interferometry. An adaptive block azimuth filtering was designed and applied to the ERS-ENVISAT tandem pair. As range bin increases, the Doppler centroid of the ERS increases while that of the ENVISAT decreases. It results in systematic increment of the Doppler centroid differences as range bin increases. The coherence of 0.7 in the near range reduced to 0.2 in the far ranges. The block azimuth filter estimates Doppler centroids of at each block, and adjusts band width of the filter. The coherence degradation caused by range-dependent Doppler centroid can be compensated by this method. The coherence is better than conventional azimuth filtering about 0.1 in far range. The resulting interferogram shows improved coherences between 0.8 to 0.4 in near and far range, respectively. However there is still gap of coherence in near and far ranges, it is resulted from inherent problem of less overlapped bandwidth at far range. Although the total improvement wits not significant, it is valuable for selection of permanent scatterers in the far range. Test results are discussed in this paper.
Year
DOI
Venue
2006
10.1109/IGARSS.2006.322
2006 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM, VOLS 1-8
Keywords
Field
DocType
Cross-interferometry, Doppler centroids, black azimuth filtering, coherence
Continuous-wave radar,Doppler radar,Computer science,Remote sensing,Optics,Azimuth,Filter (signal processing),Interferometry,Coherence (physics),Doppler effect,Centroid
Conference
ISSN
Citations 
PageRank 
2153-6996
0
0.34
References 
Authors
1
2
Name
Order
Citations
PageRank
Sang-Hoon Hong1399.33
Joong-Sun Won28016.84