Preliminary study on the evaluation of atmospheric effect to Interferometric SAR measurement 

作成者 Saito, Kazuya, 高村, 民雄, Takimoto, Kunihisa, Yamamoto, Jyouta
作成者の別表記 Takamura, Tamio
日本十進分類法 (NDC) 451, 512.75
内容 研究概要:Interferogram from a pair of complex SAR images enables to measure with the accuracy of several meter in elevation and several centimeter in surface displacement. Its measurement precision is actually reduced by some error factors. One of the most important error factors is the atmospheric propagation path delay effect. Because there is a large temporal and spatial variation of water vapor in wet region like Japan, and because its influence is not negligible for INSAR measurement. Our final objective is to quantitatively evaluate the atmospheric delay effect (especially wet delay by water vapor) included in interferogram of JERS-1 repeat pass SAR data (L-band). In atmospheric information for its evaluation, it is most efficient to use water vapor information database being provided by GPS network system of Japan Geographical Survey Institute (GSI). GPS employs same microwave L-band as SAR data, and GSI daily provides GPS water vapor information. Therefore we have started the ground based observation as a preliminary study since June 1997 in Izu peninsula where is one of the most active tectonic field. This observation has been done by using water vapor radiometer (WVR) at GPS station of GSI on SAR pass date. The acquisition data was analyzed to compare the wet delay of GPS and WVR, and to verify the usefulness of GPS for the quantitative evaluation of atmospheric effect. These observation results indicate that the wet delay of GPS corresponds well with WVR delay (correlation coefficient is 0.996, rms delay is about 1.8cm), and that GPS database is very useful in the quantitative evaluation of atmospheric delay effect. The difference of wet delay between summer and autumn observation using GPS becomes very large (more than 20 cm), and moreover its spatial distribution reveals a large variation. This suggests that a local variation in water vapor content often bring the severe height and surface displacement error for INSAR measurement.
コンテンツの種類 研究報告書 Research Paper
DCMI資源タイプ text
掲載誌情報 Proceedings of the international symposium on the atmospheric correction of satellite data and its application to global environment page.270-275 (1998)
言語 英語

Total Access Count:

480 times.

Related Materials in