{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T15:43:36Z","timestamp":1783352616155,"version":"3.54.6"},"reference-count":50,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,9,21]],"date-time":"2018-09-21T00:00:00Z","timestamp":1537488000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The neutral atmospheric delay has a great impact on synthetic aperture radar (SAR) absolute ranging and on differential interferometry. In this paper, we demonstrate its effective mitigation by means of the direction integration method using two products from the European Centre for Medium-Range Weather Forecast: ERA-Interim and operational data. Firstly, we shortly review the modeling of the neutral atmospheric delay for the direct integration method, focusing on the different refractivity models and constant coefficients available. Secondly, a thorough validation of the method is performed using two approaches. In the first approach, numerical weather prediction (NWP) derived zenith path delay (ZPD) is validated against ZPD from permanent GNSS (global navigation satellite system) stations on a global scale, demonstrating a mean accuracy of 14.5 mm for ERA-Interim. Local analysis shows a 1 mm improvement using operational data. In the second approach, NWP derived slant path delay (SPD) is validated against SAR SPD measured on corner reflectors in more than 300 TerraSAR-X High Resolution SpotLight acquisitions, demonstrating an accuracy in the centimeter range for both ERA-Interim and operational data. Finally, the application of this accurate delay estimate for the mitigation of the impact of the neutral atmosphere on SAR absolute ranging and on differential interferometry, both for individual interferograms and multi-temporal processing, is demonstrated.<\/jats:p>","DOI":"10.3390\/rs10101515","type":"journal-article","created":{"date-parts":[[2018,9,21]],"date-time":"2018-09-21T11:00:25Z","timestamp":1537527625000},"page":"1515","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Mitigation of Tropospheric Delay in SAR and InSAR Using NWP Data: Its Validation and Application Examples"],"prefix":"10.3390","volume":"10","author":[{"given":"Xiaoying","family":"Cong","sequence":"first","affiliation":[{"name":"Previously with Technische Universit\u00e4t M\u00fcnchen, Arcisstr. 21, D-80333 Munich, Germany"},{"name":"Currently with ADC Automotive Distance Control Systems GmbH, Peter-Dornier-Str. 10, D-88131 Lindau, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ulrich","family":"Balss","sequence":"additional","affiliation":[{"name":"DLR, Remote Sensing Technology Institute, Muenchener Str. 20, D-82234 Wessling, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernando","family":"Rodriguez Gonzalez","sequence":"additional","affiliation":[{"name":"DLR, Remote Sensing Technology Institute, Muenchener Str. 20, D-82234 Wessling, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Eineder","sequence":"additional","affiliation":[{"name":"DLR, Remote Sensing Technology Institute, Muenchener Str. 20, D-82234 Wessling, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Balss, U., Cong, X.Y., Brcic, R., Rexer, M., Minet, C., Breit, H., and Fritz, T. 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