{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T22:26:51Z","timestamp":1767652011996,"version":"build-2065373602"},"reference-count":68,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2022,10,18]],"date-time":"2022-10-18T00:00:00Z","timestamp":1666051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Second Tibetan Plateau Scientific Expedition and Research Program","award":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"],"award-info":[{"award-number":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"]}]},{"name":"National Natural Science Foundation of China","award":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"],"award-info":[{"award-number":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"]}]},{"name":"Foundation of the State Key Laboratory of Frozen Soil Engineering","award":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"],"award-info":[{"award-number":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"]}]},{"name":"Foundation of the State Key Laboratory for Geomechanics and Deep Underground Engineering","award":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"],"award-info":[{"award-number":["2019QZKK0905","U1703244","SKLFSE-ZY-20","SKLGDUEK 1904"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Accurate and error-free digital elevation model (DEM) data are a basic guarantee for the safe flight of unmanned aerial vehicles (UAVs) during surveys in the wild, especially in moun-tainous areas with large topographic undulations. Existing free and open-source DEM data gen-erally cover large areas, with relatively high spatial resolutions (~90, 30, and even 12.5 m), but they do not have the advantage of timeliness and cannot accurately reflect current and up-to-date topographical information in the survey area. UAV pre-scanning missions can provide highly accurate and recent terrain data as a reference for UAV route planning and ensure security for subsequent aerial survey missions; however, they are time consuming. In addition, being limited to the electric charge of the UAV, pre-scanning increases the human, financial, and time consumption of field missions, and it is not applicable for field aerial survey missions in reality, unless otherwise specified, especially in harsh environments. In this paper, we used interferometric synthetic aper-ture radar (InSAR) technology to process Sentinel-1a data to obtain the DEMs of the survey area, which were used for route planning, and other free and open-source DEMs were also used for flightline plans. The digital surface models (DSMs) were obtained from the structure of the UAV pre-scan mission images, applying structure for motion (SfM) technology as the elevation reference. Comparing the errors between the InSAR-derived DEMs and the four open-source DEMs based on the reference DSM to analyze the practicability of flight route planning, the results showed that among the four DEMs, the SRTM DEM with a spatial resolution of 30 m performed best, which was considered as the first reference for UAV route plans when the survey area in complex mountainous regions is covered with a poor or inoperative network. The InSAR-derived DEMs from the Sentinel-1 images have great potential value for UAV flight planning, with a large perpendicular baseline and short temporal baseline. This work quantitatively analyzed the errors among the different DEMs and provided a discussion regarding UAV flightline plans based on external DEMs. This can not only effectively reduce the manpower, materials, and time consumption of field operations, improving the efficiency of UAV survey tasks, but it also broadens the use of InSAR technology. Furthermore, with the launch of high-resolution SAR satellites, InSAR-derived DEMs with high spatial and temporal resolutions provide an optimistic and credible strategy for UAV route planning with small errors.<\/jats:p>","DOI":"10.3390\/rs14205215","type":"journal-article","created":{"date-parts":[[2022,10,19]],"date-time":"2022-10-19T00:58:51Z","timestamp":1666141131000},"page":"5215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Route Plans for UAV Aerial Surveys according to Different DEMs in Complex Mountainous Surroundings: A Case Study in the Zheduoshan Mountains, China"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3652-3957","authenticated-orcid":false,"given":"Qingsong","family":"Du","sequence":"first","affiliation":[{"name":"State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China"},{"name":"Da Xing\u2019anling Observation and Research Station of Frozen-Ground Engineering and Environment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Jagdaqi 165000, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4651-6251","authenticated-orcid":false,"given":"Guoyu","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China"},{"name":"Da Xing\u2019anling Observation and Research Station of Frozen-Ground Engineering and Environment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Jagdaqi 165000, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Yu","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China"},{"name":"Da Xing\u2019anling Observation and Research Station of Frozen-Ground Engineering and Environment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Jagdaqi 165000, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5357-2681","authenticated-orcid":false,"given":"Dun","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China"},{"name":"Da Xing\u2019anling Observation and Research Station of Frozen-Ground Engineering and Environment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Jagdaqi 165000, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology, Xuzhou 221116, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3913-2636","authenticated-orcid":false,"given":"Mingtang","family":"Chai","sequence":"additional","affiliation":[{"name":"School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4760-7892","authenticated-orcid":false,"given":"Shunshun","family":"Qi","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China"},{"name":"Da Xing\u2019anling Observation and Research Station of Frozen-Ground Engineering and Environment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Jagdaqi 165000, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Yapeng","family":"Cao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China"},{"name":"Da Xing\u2019anling Observation and Research Station of Frozen-Ground Engineering and Environment, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Jagdaqi 165000, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}]},{"given":"Liyun","family":"Tang","sequence":"additional","affiliation":[{"name":"School of Architecture and Civil Engineering, Xi\u2019an University of Science and Technology, Xi\u2019an 710064, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8253-234X","authenticated-orcid":false,"given":"Hailiang","family":"Jia","sequence":"additional","affiliation":[{"name":"School of Architecture and Civil Engineering, Xi\u2019an University of Science and Technology, Xi\u2019an 710064, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"936","DOI":"10.1080\/15481603.2022.2083791","article-title":"Multi-Sensor and Multi-Platform Consistency and Interoperability between UAV, Planet CubeSat, Sentinel-2, and Landsat Reflectance Data","volume":"59","author":"Jiang","year":"2022","journal-title":"GIsci. 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