{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:57:36Z","timestamp":1760241456523,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,3,12]],"date-time":"2018-03-12T00:00:00Z","timestamp":1520812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>For accurate motion compensation (MOCO) in airborne synthetic aperture radar (SAR) imaging, a high-precision inertial navigation system (INS) is required. However, an INS is not always precise enough or is sometimes not even included in airborne SAR systems. In this paper, a new, raw, data-based range-invariant motion compensation approach, which can effectively extract the displacements in the line-of-sight (LOS) direction, is proposed for high-resolution sliding spotlight SAR mode. In this approach, the sub-aperture radial accelerations of the airborne platform are estimated via a well-developed weighted total least square (WTLS) method considering the time-varying beam direction. The effectiveness of the proposed approach is validated by two airborne sliding spotlight C band SAR raw datasets containing different types of terrain, with a high spatial resolution of about 0.15 m in azimuth.<\/jats:p>","DOI":"10.3390\/s18030842","type":"journal-article","created":{"date-parts":[[2018,3,12]],"date-time":"2018-03-12T13:13:48Z","timestamp":1520860428000},"page":"842","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Raw Data-Based Motion Compensation for High-Resolution Sliding Spotlight Synthetic Aperture Radar"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4358-6449","authenticated-orcid":false,"given":"Ning","family":"Li","sequence":"first","affiliation":[{"name":"School of Computer and Information Engineering, Henan University, Kaifeng 475004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shilin","family":"Niu","sequence":"additional","affiliation":[{"name":"School of Computer and Information Engineering, Henan University, Kaifeng 475004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhengwei","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Computer and Information Engineering, Henan University, Kaifeng 475004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yabo","family":"Liu","sequence":"additional","affiliation":[{"name":"Space Microwave Remote Sensing System Department, Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiaqi","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Computer and Information Engineering, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,3,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"611","DOI":"10.1109\/36.581976","article-title":"Signal properties of spaceborne squint mode SAR","volume":"35","author":"Davidson","year":"1997","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_2","first-page":"17","article-title":"A new algorithm for processing hybrid strip-map\/spotlight mode synthetic aperture radar data","volume":"4173","author":"Fornaro","year":"2000","journal-title":"Proc. SPIE Int. Soc. Opt. Eng."},{"key":"ref_3","unstructured":"Mittermayer, J., Lord, R.T., and Boerner, E. (2003, January 21\u201325). Sliding spotlight SAR processing for TerraSAR-X using a new formulation of the extended chirp scaling algorithm. Proceedings of the 2003 IEEE International Geoscience and Remote Sensing Symposium, IGARSS 2003, Toulouse, France."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"770","DOI":"10.1109\/TGRS.2009.2027701","article-title":"Processing of sliding spotlight and TOPS SAR data using baseband azimuth scaling","volume":"48","author":"Prats","year":"2010","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1993","DOI":"10.1109\/36.951090","article-title":"Spotlight SAR data focusing based on a two-step processing approach","volume":"39","author":"Lanari","year":"2001","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1049\/ip-rsn:20010662","article-title":"New approach for hybrid strip-map\/spotlight SAR data focusing","volume":"148","author":"Lanari","year":"2001","journal-title":"IEE Proc.-Radar Sonar Navig."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2889","DOI":"10.1109\/TGRS.2011.2174460","article-title":"Extended two-step focusing approach for squinted spotlight SAR imaging","volume":"50","author":"An","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"4596","DOI":"10.1109\/TGRS.2013.2282863","article-title":"Full-aperture SAR data focusing in the spaceborne squinted sliding-spotlight mode","volume":"52","author":"Xu","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"997","DOI":"10.1109\/7.784069","article-title":"Trajectory deviations in airborne SAR: Analysis and compensation","volume":"35","author":"Fornaro","year":"1999","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1338","DOI":"10.1109\/TAES.2005.1561888","article-title":"Motion compensation errors: Effects on the accuracy of airborne SAR images","volume":"41","author":"Fornaro","year":"2005","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1109\/36.312891","article-title":"Airborne SAR processing of highly squinted data using a chirp scaling approach with integrated motion compensation","volume":"32","author":"Moreira","year":"1994","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"952","DOI":"10.1109\/TGRS.2008.2006275","article-title":"Chirp-scaling algorithm for bistatic SAR data in the constant-offset configuration","volume":"47","author":"Wang","year":"2009","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1109\/7.272285","article-title":"Subaperture autofocus for synthetic aperture radar","volume":"30","author":"Calloway","year":"1994","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1109\/7.303752","article-title":"Phase gradient autofocus\u2014A robust tool for high resolution SAR phase correction","volume":"30","author":"Wahl","year":"1994","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1185","DOI":"10.1109\/7.532282","article-title":"Autofocusing of inverse synthetic aperture radar images using contrast optimization","volume":"32","author":"Berizzi","year":"1996","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1240","DOI":"10.1109\/7.805442","article-title":"Autofocusing of ISAR images based on entropy minimization","volume":"35","author":"Li","year":"1999","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2870","DOI":"10.1109\/TGRS.2009.2015657","article-title":"Motion compensation for UAV SAR based on raw radar data","volume":"47","author":"Xing","year":"2009","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"083664","DOI":"10.1117\/1.JRS.8.083664","article-title":"Motion error correction approach for high-resolution synthetic aperture radar imaging","volume":"8","author":"Jia","year":"2014","journal-title":"J. Appl. Remote Sens."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3202","DOI":"10.1109\/TGRS.2011.2180392","article-title":"A robust motion compensation approach for UAV SAR imagery","volume":"50","author":"Zhang","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2780","DOI":"10.1109\/TGRS.2011.2175737","article-title":"robust motion error estimation method based on raw data","volume":"50","author":"Li","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"468","DOI":"10.1109\/TAES.2013.6404115","article-title":"Multi-subaperture PGA for SAR autofocusing","volume":"49","author":"Zhu","year":"2013","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_22","first-page":"317","article-title":"Motion compensation using sub-strip PGA","volume":"31","author":"Zhang","year":"2014","journal-title":"J. Electron."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/3\/842\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T14:56:45Z","timestamp":1760194605000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/3\/842"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,3,12]]},"references-count":22,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2018,3]]}},"alternative-id":["s18030842"],"URL":"https:\/\/doi.org\/10.3390\/s18030842","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2018,3,12]]}}}