{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,18]],"date-time":"2025-11-18T12:30:08Z","timestamp":1763469008816,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2024,11,8]],"date-time":"2024-11-08T00:00:00Z","timestamp":1731024000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["2022YFC3003202","2023YFB3905004"],"award-info":[{"award-number":["2022YFC3003202","2023YFB3905004"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Key Research and Development Program of China","award":["2022YFC3003202","2023YFB3905004"],"award-info":[{"award-number":["2022YFC3003202","2023YFB3905004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The integration of ground-penetrating radar (GPR) with unmanned aerial vehicles (UAVs) enables efficient non-contact detection, performing exceptionally well in complex terrains and extreme environments. However, challenges in data processing and interpretation remain significant obstacles to fully utilizing this technology. To mitigate the effects of numerical dispersion, this paper develops a high-order finite-difference time-domain (FDTD(2,4)) three-dimensional code suitable for airborne GPR numerical simulations. The simulation results are compared with traditional FDTD methods, validating the accuracy of the proposed approach. Additionally, a Kirchhoff migration algorithm that considers the influence of the air layer is developed for airborne GPR. Different processing strategies are applied to flat and undulating terrain models, significantly improving the identification of shallowly buried targets. Particularly under undulating terrain conditions, the energy ratio method is introduced, effectively suppressing the interference of surface reflections caused by terrain variations. This innovative approach offers a new technical pathway for efficient GPR data processing in complex terrains. The study provides new insights and methods for the practical application of airborne GPR.<\/jats:p>","DOI":"10.3390\/rs16224174","type":"journal-article","created":{"date-parts":[[2024,11,12]],"date-time":"2024-11-12T03:53:14Z","timestamp":1731383594000},"page":"4174","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Research on Airborne Ground-Penetrating Radar Imaging Technology in Complex Terrain"],"prefix":"10.3390","volume":"16","author":[{"given":"Yuelong","family":"Chi","sequence":"first","affiliation":[{"name":"College of Geophysics, Chengdu University of Technology, Chengdu 610059, China"},{"name":"The Engineering & Technical College of Chengdu University of Technology, Leshan 614000, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-8621-4231","authenticated-orcid":false,"given":"Su","family":"Pang","sequence":"additional","affiliation":[{"name":"College of Geophysics, Chengdu University of Technology, Chengdu 610059, China"},{"name":"The Engineering & Technical College of Chengdu University of Technology, Leshan 614000, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9270-5969","authenticated-orcid":false,"given":"Lifeng","family":"Mao","sequence":"additional","affiliation":[{"name":"College of Geophysics, Chengdu University of Technology, Chengdu 610059, China"},{"name":"The School of Physics, Chemistry and Earth Sciences, The University of Adelaide, Adelaide, SA 5000, Australia"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-5587-5241","authenticated-orcid":false,"given":"Qiang","family":"Zhou","sequence":"additional","affiliation":[{"name":"College of Geophysics, Chengdu University of Technology, Chengdu 610059, China"},{"name":"The Engineering & Technical College of Chengdu University of Technology, Leshan 614000, China"}]},{"given":"Yuehua","family":"Chi","sequence":"additional","affiliation":[{"name":"College of Computer and Information Science College of Software, Southwest University, Chongqing 400700, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/0926-9851(95)90040-3","article-title":"Applications of ground penetrating radar in assessing some geological hazards: Examples of groundwater contamination, faults, cavities","volume":"33","author":"Benson","year":"1995","journal-title":"J. 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