{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T23:33:19Z","timestamp":1768433599687,"version":"3.49.0"},"reference-count":46,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,15]],"date-time":"2018-10-15T00:00:00Z","timestamp":1539561600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000923","name":"Australian Research Council","doi-asserted-by":"publisher","award":["DP140101488"],"award-info":[{"award-number":["DP140101488"]}],"id":[{"id":"10.13039\/501100000923","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We investigate footprint geolocation uncertainties of a spectroradiometer mounted on an unmanned aircraft system (UAS). Two microelectromechanical systems-based inertial measurement units (IMUs) and global navigation satellite system (GNSS) receivers were used to determine the footprint location and extent of the spectroradiometer. Errors originating from the on-board GNSS\/IMU sensors were propagated through an aerial data georeferencing model, taking into account a range of values for the spectroradiometer field of view (FOV), integration time, UAS flight speed, above ground level (AGL) flying height, and IMU grade. The spectroradiometer under nominal operating conditions (8     \u2218     FOV, 10 m AGL height, 0.6 s integration time, and 3 m\/s flying speed) resulted in footprint extent of 140 cm across-track and 320 cm along-track, and a geolocation uncertainty of 11 cm. Flying height and orientation measurement accuracy had the largest influence on the geolocation uncertainty, whereas the FOV, integration time, and flying speed had the biggest impact on the size of the footprint. Furthermore, with an increase in flying height, the rate of increase in geolocation uncertainty was found highest for a low-grade IMU. To increase the footprint geolocation accuracy, we recommend reducing flying height while increasing the FOV which compensates the footprint area loss and increases the signal strength. The disadvantage of a lower flying height and a larger FOV is a higher sensitivity of the footprint size to changing distance from the target. To assist in matching the footprint size to uncertainty ratio with an appropriate spatial scale, we list the expected ratio for a range of IMU grades, FOVs and AGL heights.<\/jats:p>","DOI":"10.3390\/s18103465","type":"journal-article","created":{"date-parts":[[2018,10,16]],"date-time":"2018-10-16T02:52:53Z","timestamp":1539658373000},"page":"3465","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Error Budget for Geolocation of Spectroradiometer Point Observations from an Unmanned Aircraft System"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2852-4204","authenticated-orcid":false,"given":"Deepak","family":"Gautam","sequence":"first","affiliation":[{"name":"Discipline of Geography and Spatial Sciences, School of Technology, Environments and Design, University of Tasmania, Hobart TAS 7005, Australia"},{"name":"School of Agriculture, Food and Wine, Faculty of Sciences, University of Adelaide, Adelaide SA 5064, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christopher","family":"Watson","sequence":"additional","affiliation":[{"name":"Discipline of Geography and Spatial Sciences, School of Technology, Environments and Design, University of Tasmania, Hobart TAS 7005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9468-4516","authenticated-orcid":false,"given":"Arko","family":"Lucieer","sequence":"additional","affiliation":[{"name":"Discipline of Geography and Spatial Sciences, School of Technology, Environments and Design, University of Tasmania, Hobart TAS 7005, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1271-8103","authenticated-orcid":false,"given":"Zbyn\u011bk","family":"Malenovsk\u00fd","sequence":"additional","affiliation":[{"name":"Discipline of Geography and Spatial Sciences, School of Technology, Environments and Design, University of Tasmania, Hobart TAS 7005, Australia"},{"name":"Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong NSW 2522, Australia"},{"name":"Department of Remote Sensing, Global Change Research Institute CAS, B\u011blidla 986\/4a, CZ-60300 Brno, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"281","DOI":"10.14358\/PERS.81.4.281","article-title":"Overview and Current Status of Remote Sensing Applications Based on Unmanned Aerial Vehicles (UAVs)","volume":"81","author":"Pajares","year":"2015","journal-title":"Photogramm. 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