{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T10:10:11Z","timestamp":1766139011364,"version":"build-2065373602"},"reference-count":51,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2024,12,20]],"date-time":"2024-12-20T00:00:00Z","timestamp":1734652800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61971163","62201612","62371170","6240011408","62401615","2024M754185"],"award-info":[{"award-number":["61971163","62201612","62371170","6240011408","62401615","2024M754185"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["61971163","62201612","62371170","6240011408","62401615","2024M754185"],"award-info":[{"award-number":["61971163","62201612","62371170","6240011408","62401615","2024M754185"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A bistatic synthetic aperture radar (BiSAR) system with a Medium-Earth-Orbit (MEO) SAR transmitter and high-maneuvering receiver (MEO\/HM-BiSAR) can achieve a wide swath and high resolution. However, due to the complex orbit characteristics and the nonlinear trajectory of the receiver, MEO\/HM-BiSAR high-resolution imaging faces two major challenges. First, the complex geometric configuration of the BiSAR platforms is difficult to model accurately, and the \u2018non-stop-go\u2019 effects should also be considered. Second, non-negligible wavefront curvature caused by the nonlinear trajectories introduces residual phase errors. The existing spaceborne BiSAR imaging algorithms often suffer from image defocusing if applied to MEO\/HM-BiSAR. To address these problems, a novel high-resolution imaging algorithm named MSSWCC (Modified Second-Order Space-Variant Wavefront Curvature Correction) is proposed. First, a high-precision range model is established based on an analysis of MEO SAR\u2019s orbital characteristics and the receiver\u2019s curved trajectory. Based on the echo model, the wavefront curvature error is then addressed by two-dimensional Taylor expansion to obtain the analytical expressions for the high-order phase errors. By analyzing the phase errors in the wavenumber domain, the compensation functions can be designed. The MSSWCC algorithm not only corrects the geometric distortion through reverse projection, but it also compensates for the second-order residual spatial-variant phase errors by the analytical expressions for the two-dimensional phase errors. It can achieve high-resolution imaging ability in large imaging scenes with low computational load. Simulations and real experiments validate the high-resolution imaging capabilities of the proposed MSSWCC algorithm in MEO\/HM-BiSAR.<\/jats:p>","DOI":"10.3390\/rs16244768","type":"journal-article","created":{"date-parts":[[2024,12,23]],"date-time":"2024-12-23T09:13:38Z","timestamp":1734945218000},"page":"4768","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["A High-Resolution Spotlight Imaging Algorithm via Modified Second-Order Space-Variant Wavefront Curvature Correction for MEO\/HM-BiSAR"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9069-8235","authenticated-orcid":false,"given":"Hang","family":"Ren","sequence":"first","affiliation":[{"name":"School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zheng","family":"Lu","sequence":"additional","affiliation":[{"name":"Institute of Remote Sensing Satellite, China Academy of Space Technology, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gaopeng","family":"Li","sequence":"additional","affiliation":[{"name":"School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yun","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xueying","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yalin","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Mathematics and Statistics, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Long","family":"Li","sequence":"additional","affiliation":[{"name":"School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0009-4428","authenticated-orcid":false,"given":"Xin","family":"Qi","sequence":"additional","affiliation":[{"name":"Beijing Institute of Astronautical Systems Engineering, Beijing 100076, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qinglong","family":"Hua","sequence":"additional","affiliation":[{"name":"School of Electronics and Information Engineering, Harbin Institute of Technology, Harbin 150001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chang","family":"Ding","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Artificially Structured Functional Materials, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huilin","family":"Mu","sequence":"additional","affiliation":[{"name":"Air Defense and Antimissile School, Air Force Engineering University, Xi\u2019an 710051, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong","family":"Du","sequence":"additional","affiliation":[{"name":"China Mobile Chengdu Institute of Research and Development, Chengdu 610213, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,20]]},"reference":[{"key":"ref_1","unstructured":"Matar, J., Lopez-Dekker, P., and Krieger, G. (2016, January 6\u20139). Potentials and Limitations of MEO SAR. Proceedings of the European Conference on Synthetic Aperture Radar, Hamburg, Germany."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1313","DOI":"10.1109\/TGRS.2019.2945875","article-title":"MEO SAR: System Concepts and Analysis","volume":"58","author":"Matar","year":"2020","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"9188","DOI":"10.1109\/TGRS.2019.2925385","article-title":"Highly Squinted MEO SAR Focusing Based on Extended Omega-K Algorithm and Modified Joint Time and Doppler Resampling","volume":"57","author":"Liu","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3963","DOI":"10.1109\/TGRS.2018.2818262","article-title":"Focusing of Medium-Earth-Orbit SAR Using an ASE-Velocity Model Based on MOCO Principle","volume":"56","author":"Chen","year":"2018","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"5477","DOI":"10.1109\/TGRS.2020.2966581","article-title":"Focusing of MEO SAR Data Based on Principle of Optimal Imaging Coordinate System","volume":"58","author":"Liu","year":"2020","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"8500205","DOI":"10.1109\/LGRS.2023.3337042","article-title":"On the Equivalence of LEO-SAR Constellations and Complex High-Orbit SAR Systems for the Monitoring of Large-Scale Processes","volume":"21","author":"Matar","year":"2024","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"5227522","DOI":"10.1109\/TGRS.2024.3493614","article-title":"Focusing of Highly Squinted Bistatic SAR With MEO Transmitter and High Maneuvering Platform Receiver in Curved Trajectory","volume":"62","author":"Zhang","year":"2024","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Song, X., Li, Y., Wu, C., Sun, Z., Cen, X., and Zhang, T. (2021, January 15\u201319). A New Frenquency-Domain Imaging for High-maneuverability Bistatic Forward-looking SAR. Proceedings of the 2021 CIE International Conference on Radar (Radar), Haikou, China.","DOI":"10.1109\/Radar53847.2021.10028581"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.3390\/rs16071131","article-title":"An Improved NLCS Algorithm Based on Series Reversion and Elliptical Model Using Geosynchronous Spaceborne\u2014Airborne UHF UWB Bistatic SAR for Oceanic Scene Imaging","volume":"16","author":"Hu","year":"2024","journal-title":"Remote Sens."},{"key":"ref_10","first-page":"5205813","article-title":"A Novel Motion Compensation Algorithm Based on Motion Sensitivity Analysis for Mini-UAV-Based BiSAR System","volume":"60","author":"Wang","year":"2022","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Zhang, S., Liu, F., Wang, Z., Wang, C., Lv, R., and Yao, D. (2022, January 19\u201322). A LEO Spaceborne-Airborne Bistatic SAR Imaging Experiment. Proceedings of the IEEE International Conference on Signal Processing, Communications and Computing, ICSPCC, Bali, Indonesia.","DOI":"10.1109\/ICSPCC55723.2022.9984341"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"346","DOI":"10.3390\/rs11030346","article-title":"Modeling and precise processing for spaceborne transmitter\/missile-borne receiver SAR signals","volume":"11","author":"Tang","year":"2019","journal-title":"Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1214","DOI":"10.1109\/TGRS.2020.3002900","article-title":"Geosynchronous Spaceborne\u2013Airborne Bistatic SAR Data Focusing Using a Novel Range Model Based on One-Stationary Equivalence","volume":"59","author":"Sun","year":"2021","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"5976","DOI":"10.1109\/TGRS.2020.2974531","article-title":"A Novel Azimuth Spectrum Reconstruction and Imaging Method for Moving Targets in Geosynchronous Spaceborne\u2013Airborne Bistatic Multichannel SAR","volume":"58","author":"Zhang","year":"2020","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"5207714","DOI":"10.1109\/TGRS.2021.3081099","article-title":"Geosynchronous Spaceborne\u2013Airborne Bistatic SAR Imaging Based on Fast Low-Rank and Sparse Matrices Recovery","volume":"60","author":"An","year":"2022","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Tang, W., Huang, B., Wang, W.Q., Zhang, S., Liu, W., and Wang, Y. (2019, January 26\u201329). A Novel Imaging Algorithm for Forward-looking GEO\/Missile-borne Bistatic SAR. Proceedings of the Asia-Pacific Conference on Synthetic Aperture Radar APSAR, Xiamen, China.","DOI":"10.1109\/APSAR46974.2019.9048524"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"5072","DOI":"10.1109\/JSTARS.2021.3077003","article-title":"Ground Moving Target Indication for the Geosynchronous-Low Earth Orbit Bistatic Multichannel SAR System","volume":"14","author":"Zhang","year":"2021","journal-title":"IEEE J. Sel. Topics Appl. Earth Observ. Remote Sens."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1861","DOI":"10.1109\/TGRS.2018.2869835","article-title":"Azimuth Signal Multichannel Reconstruction and Channel Configuration Design for Geosynchronous Spaceborne\u2013Airborne Bistatic SAR","volume":"57","author":"Wu","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2476","DOI":"10.1109\/JSTARS.2022.3153824","article-title":"Focusing High Maneuvering Bistatic Forward-Looking SAR With Stationary Transmitter Using Extended Keystone Transform and Modified Frequency Nonlinear Chirp Scaling","volume":"15","author":"Ding","year":"2022","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5240814","DOI":"10.1109\/TGRS.2022.3228803","article-title":"Focusing High-Maneuverability Bistatic Forward-Looking SAR Using Extended Azimuth Nonlinear Chirp Scaling Algorithm","volume":"60","author":"Song","year":"2022","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"3757","DOI":"10.1109\/JSTARS.2020.2999966","article-title":"A Generalized Wavefront-Curvature-Corrected Polar Format Algorithm to Focus Bistatic SAR Under Complicated Flight Paths","volume":"13","author":"Miao","year":"2020","journal-title":"IEEE J. Sel. Topics Appl. Earth Observ. Remote Sens."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"31143","DOI":"10.1109\/ACCESS.2020.2971660","article-title":"High-Efficiency and High-Precision Reconstruction Strategy for P-Band Ultra-Wideband Bistatic Synthetic Aperture Radar Raw Data Including Motion Errors","volume":"8","author":"Xie","year":"2020","journal-title":"IEEE Access"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2380","DOI":"10.1109\/LGRS.2017.2765675","article-title":"High-Resolution Wide-Swath Imaging of Spaceborne Multichannel Bistatic SAR with Inclined Geosynchronous Illuminator","volume":"14","author":"Wang","year":"2017","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"3949","DOI":"10.1109\/JSTARS.2019.2945118","article-title":"Fast Factorized Backprojection Imaging Algorithm Integrated With Motion Trajectory Estimation for Bistatic Forward-Looking SAR","volume":"12","author":"Pu","year":"2019","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1508","DOI":"10.1109\/JSTARS.2019.2907138","article-title":"A New Fast Factorized Back Projection Algorithm for Bistatic Forward-Looking SAR Imaging Based on Orthogonal Elliptical Polar Coordinate","volume":"12","author":"Zhou","year":"2019","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2215","DOI":"10.3390\/rs15082215","article-title":"Fast Factorized Backprojection Algorithm in Orthogonal Elliptical Coordinate System for Ocean Scenes Imaging Using Geosynchronous Spaceborne\u2014Airborne VHF UWB Bistatic SAR","volume":"15","author":"Hu","year":"2023","journal-title":"Remote Sens."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1152","DOI":"10.3390\/s17051152","article-title":"An Improved RD Algorithm for Maneuvering Bistatic Forward-Looking SAR Imaging with a Fixed Transmitter","volume":"17","author":"Yuan","year":"2017","journal-title":"Sensors"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1109\/TGRS.2019.2936255","article-title":"Focusing the L-Band Spaceborne Bistatic SAR Mission Data Using a Modified RD Algorithm","volume":"58","author":"Li","year":"2020","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2493","DOI":"10.1109\/TGRS.2008.917599","article-title":"Focusing Bistatic SAR Data Using the Nonlinear Chirp Scaling Algorithm","volume":"46","author":"Wong","year":"2008","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1543","DOI":"10.1109\/JSTARS.2015.2507260","article-title":"A New Imaging Algorithm for Forward-Looking Missile-Borne Bistatic SAR","volume":"9","author":"Chen","year":"2016","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1916","DOI":"10.3390\/rs13101916","article-title":"Focus Improvement of Airborne High-Squint Bistatic SAR Data Using Modified Azimuth NLCS Algorithm Based on Lagrange Inversion Theorem","volume":"13","author":"Deng","year":"2021","journal-title":"Remote Sens."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1185","DOI":"10.1109\/TMTT.2019.2955126","article-title":"Millimeter-Wave Image Reconstruction Algorithm for One-Stationary Bistatic SAR","volume":"68","author":"Wang","year":"2020","journal-title":"IEEE Trans. Microw. Theory Tech."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"940","DOI":"10.1109\/TAES.2012.6178040","article-title":"Space-Variant Filtering for Wavefront Curvature Correction in Polar Formatted Bistatic SAR Image","volume":"48","author":"Wang","year":"2012","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"6018","DOI":"10.1109\/TGRS.2019.2903878","article-title":"PFA for Bistatic Forward-Looking SAR Mounted on High-Speed Maneuvering Platforms","volume":"57","author":"Zhang","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_35","first-page":"5213218","article-title":"High-Resolution Bistatic Spotlight SAR Imagery With General Configuration and Accelerated Track","volume":"61","author":"Wang","year":"2023","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"4008005","DOI":"10.1109\/LGRS.2020.3047617","article-title":"A Modified Space-Variant Phase Filtering Algorithm of PFA for Bistatic SAR","volume":"19","author":"Han","year":"2022","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"5221514","DOI":"10.1109\/TGRS.2023.3332759","article-title":"Efficient BiSAR PFA Wavefront Curvature Compensation for Arbitrary Radar Flight Trajectories","volume":"61","author":"Shi","year":"2023","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_38","unstructured":"Huang, L., Qiu, X., Hu, D., and Ding, C. (2009, January 26\u201330). An advanced 2-D spectrum for high-resolution and MEO spaceborne SAR. Proceedings of the 2009 2nd Asian-Pacific Conference on Synthetic Aperture Radar, Xi\u2019an, China."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"5222314","DOI":"10.1109\/TGRS.2023.3335908","article-title":"Analysis of Modeling and 2-D Resolution of Satellite\u2013Missile Borne Bistatic Forward-Looking SAR","volume":"61","author":"Qian","year":"2023","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Huo, T., Li, Y., Yang, C., Cao, C., and Wang, Y. (2022, January 17\u201322). A Novel Imaging Method for MEO SAR-GMTI Systems. Proceedings of the IGARSS 2022-2022 IEEE International Geoscience and Remote Sensing Symposium, Kuala Lumpur, Malaysia.","DOI":"10.1109\/IGARSS46834.2022.9883559"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1120","DOI":"10.1109\/JSTARS.2015.2399103","article-title":"Acceleration Model Analyses and Imaging Algorithm for Highly Squinted Airborne Spotlight-Mode SAR with Maneuvers","volume":"8","author":"Tang","year":"2015","journal-title":"IEEE J. Sel. Top. Appl. Earth Obs. Remote Sens."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"5211512","DOI":"10.1109\/TGRS.2024.3393758","article-title":"A Bidirectional Resampling Imaging Algorithm for High Maneuvering Bistatic Forward-Looking SAR Based on Chebyshev Orthogonal Decomposition","volume":"62","author":"Zheng","year":"2024","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1109\/TGRS.2020.2992744","article-title":"Nonambiguous Image Formation for Low-Earth-Orbit SAR with Geosynchronous Illumination Based on Multireceiving and CAMP","volume":"59","author":"An","year":"2021","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"3311","DOI":"10.1109\/JSEN.2018.2809508","article-title":"A Space-Variant Phase Filtering Imaging Algorithm for Missile-Borne BiSAR With Arbitrary Configuration and Curved Track","volume":"18","author":"Deng","year":"2018","journal-title":"IEEE Sens. J."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"10766","DOI":"10.1109\/JSEN.2020.2994752","article-title":"Focusing Spotlight-Mode Bistatic GEO SAR with a Stationary Receiver Using Time-Doppler Resampling","volume":"20","author":"Guo","year":"2020","journal-title":"IEEE Sens. J."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1590","DOI":"10.1109\/LGRS.2019.2902036","article-title":"Geosynchronous Spaceborne\u2013Airborne Multichannel Bistatic SAR Imaging Using Weighted Fast Factorized Backprojection Method","volume":"16","author":"An","year":"2019","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"2815","DOI":"10.1109\/TAES.2016.150589","article-title":"Fast corrections for polar format algorithm with a curved flight path","volume":"52","author":"Gorham","year":"2016","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"4765","DOI":"10.1109\/TGRS.2020.3011420","article-title":"Using an Equivalence-Based Approach to Derive 2-D Spectrum of BiSAR Data and Implementation Into an RDA Processor","volume":"59","author":"Xiong","year":"2021","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_49","first-page":"3122","article-title":"Research on Key Technique of Highly Squinted Sliding SpotlightSAR Imaging with Varied Receiving Range Bin","volume":"38","author":"Xin","year":"2016","journal-title":"J. Electron. Inf. Technol."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Xin, N., Shijian, S., Hui, Y., Ying, L., Long, Z., and Wanming, L. (2018, January 22\u201327). A wide-field SAR polar format algorithm based on quadtree sub-image segmentation. Proceedings of the IGARSS 2018-2018 IEEE International Geoscience and Remote Sensing Symposium, Valencia, Spain.","DOI":"10.1109\/IGARSS.2018.8651415"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"147682","DOI":"10.1109\/ACCESS.2020.3015437","article-title":"A Quadtree Beam-Segmenting Based Wide-Swath SAR Polar Format Algorithm","volume":"8","author":"Nie","year":"2020","journal-title":"IEEE Access"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/16\/24\/4768\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:57:11Z","timestamp":1760115431000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/16\/24\/4768"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,20]]},"references-count":51,"journal-issue":{"issue":"24","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["rs16244768"],"URL":"https:\/\/doi.org\/10.3390\/rs16244768","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2024,12,20]]}}}