DATA OPTIMALIZATION IN PERMANENT SCATTERER INTERFEROMETRIC SYNTHETIC APERTURE RADAR (PS-INSAR) TECHNIQUE FOR LAND SUBSIDENCE ESTIMATION

摘要

Since the introduction of the persistent scatterer technique (PS-InSAR) in the early 1999, the applicability of radar interferometry has increased considerably. In this research, PS-InSAR technique is proposed to retrieve the volume change of long-term continuously land deformation. This technique is used to analyze subsidence in Bandung City, West Java-Indonesia by assessing 19 ALOS PALSAR images (Japanese L band spaceborne) during the periods of July 2007-February 2011. In this research, data are optimized by reducing set data images with iterative PS-InSAR processing. This PS-InSAR processing chain based on a rigid quality assessment of the estimated parameter like minimum coherence (0.9) and PS density point (200), in order to get an optimum quality of light PS-InSAR (LPS-InSAR) concept technique. Moreover, a strict quality validation of PS-InSAR with other geodetic techniques such as DInSAR and GPS methods. The result of validation has resulted such as 1,4 ± 1,4 cm/year (PS InSAR-DInSAR) and 1,6 ± 0,7 cm/year (PS-InSAR-GPS). For land subsidence velocity in Bandung City has results between 0,6 ± 0,4 cm/year and 2,1 ± 1,2 cm/year. This research shows a capability of data optimalization in PS-InSAR technique as basic concept of LPS-InSAR processing.