{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,20]],"date-time":"2026-06-20T07:46:53Z","timestamp":1781941613616,"version":"3.54.5"},"reference-count":56,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2017,4,27]],"date-time":"2017-04-27T00:00:00Z","timestamp":1493251200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Thanks to their flexibility and availability at reduced costs, Unmanned Aerial Vehicles (UAVs) have been recently used on a wide range of applications and conditions. Among these, they can play an important role in monitoring critical events (e.g., disaster monitoring) when the presence of humans close to the scene shall be avoided for safety reasons, in precision farming and surveying. Despite the very large number of possible applications, their usage is mainly limited by the availability of the Global Navigation Satellite System (GNSS) in the considered environment: indeed, GNSS is of fundamental importance in order to reduce positioning error derived by the drift of (low-cost) Micro-Electro-Mechanical Systems (MEMS) internal sensors. In order to make the usage of UAVs possible even in critical environments (when GNSS is not available or not reliable, e.g., close to mountains or in city centers, close to high buildings), this paper considers the use of a low cost Ultra Wide-Band (UWB) system as the positioning method. Furthermore, assuming the use of a calibrated camera, UWB positioning is exploited to achieve metric reconstruction on a local coordinate system. Once the georeferenced position of at least three points (e.g., positions of three UWB devices) is known, then georeferencing can be obtained, as well. The proposed approach is validated on a specific case study, the reconstruction of the fa\u00e7ade of a university building. Average error on 90 check points distributed over the building fa\u00e7ade, obtained by georeferencing by means of the georeferenced positions of four UWB devices at fixed positions, is 0.29 m. For comparison, the average error obtained by using four ground control points is 0.18 m.<\/jats:p>","DOI":"10.3390\/rs9050414","type":"journal-article","created":{"date-parts":[[2017,4,27]],"date-time":"2017-04-27T13:01:15Z","timestamp":1493298075000},"page":"414","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["A Low Cost UWB Based Solution for Direct Georeferencing UAV Photogrammetry"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8028-2815","authenticated-orcid":false,"given":"Andrea","family":"Masiero","sequence":"first","affiliation":[{"name":"Interdepartmental Research Center of Geomatics (CIRGEO), University of Padova, via dell\u2019Universit\u00e0 16, 35020 Legnaro (PD), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Fissore","sequence":"additional","affiliation":[{"name":"Interdepartmental Research Center of Geomatics (CIRGEO), University of Padova, via dell\u2019Universit\u00e0 16, 35020 Legnaro (PD), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Vettore","sequence":"additional","affiliation":[{"name":"Interdepartmental Research Center of Geomatics (CIRGEO), University of Padova, via dell\u2019Universit\u00e0 16, 35020 Legnaro (PD), Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,4,27]]},"reference":[{"key":"ref_1","first-page":"C22","article-title":"UAV photogrammetry for mapping and 3d modeling\u2013Current status and future perspectives","volume":"38","author":"Remondino","year":"2011","journal-title":"Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s12518-013-0120-x","article-title":"UAV for 3D mapping applications: A review","volume":"6","author":"Nex","year":"2014","journal-title":"Appl. Geomat."},{"key":"ref_3","first-page":"1373","article-title":"Low cost UAV for post-disaster assessment","volume":"37","author":"Bendea","year":"2008","journal-title":"Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.isprsjprs.2014.02.013","article-title":"Unmanned aerial systems for photogrammetry and remote sensing: A review","volume":"92","author":"Colomina","year":"2014","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_5","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. Eng. Remote Sens."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"6560","DOI":"10.3390\/s150306560","article-title":"New Calibration Method Using Low Cost MEM IMUs to Verify the Performance of UAV-Borne MMS Payloads","volume":"15","author":"Chiang","year":"2015","journal-title":"Sensors"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1002\/j.2161-4296.1998.tb02387.x","article-title":"Navigating urban areas by VISAT\u2013A mobile mapping system integrating GPS\/INS\/digital cameras for GIS applications","volume":"45","author":"Schwarz","year":"1998","journal-title":"Navigation"},{"key":"ref_8","unstructured":"Barbarella, M., Gandolfi, S., Meffe, A., and Burchi, A. (2011, January 20\u201323). Improvement of an MMS Trajectory, in Presence of GPS Outage, Using Virtual Positions. Proceedings of the ION GNSS 24th International Technical Meeting of the Satellite Division, Portland, OR, USA."},{"key":"ref_9","unstructured":"(2017, April 24). Javad. Available online: https:\/\/www.javad.com\/."},{"key":"ref_10","unstructured":"(2017, April 24). Topcon. Available online: http:\/\/global.topcon.com\/."},{"key":"ref_11","unstructured":"(2017, April 24). Maxtena. Available online: https:\/\/www.maxtena.com\/."},{"key":"ref_12","unstructured":"(2017, April 24). SenseFly eBee. Available online: https:\/\/www.sensefly.com\/drones\/ebee.html."},{"key":"ref_13","unstructured":"Toth, C., Jozkow, G., Ostrowski, S., and Grejner-Brzezinska, D. (2015, January 9\u201311). Positioning Slow Moving Platforms by UWB Technology in GPS\u2013Challenged Areas. Proceedings of the 9th International Symposium on Mobile Mapping Technology, MMT, Sydney, Australia."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Tiemann, J., Schweikowski, F., and Wietfeld, C. (2015, January 13\u201316). Design of an UWB Indoor-Positioning System for UAV Navigation in GNSS-Denied Environments. Proceedings of the 2015 International Conference on Indoor Positioning and Indoor Navigation (IPIN), Banff, AB, Canada.","DOI":"10.1109\/IPIN.2015.7346960"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1017\/S0373463312000331","article-title":"Effective adaptive Kalman filter for MEMS-IMU\/magnetometers integrated attitude and heading reference systems","volume":"66","author":"Li","year":"2013","journal-title":"J. Navig."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"5742","DOI":"10.3390\/s140405742","article-title":"Context-Aware Personal Navigation Using Embedded Sensor Fusion in Smartphones","volume":"14","author":"Saeedi","year":"2014","journal-title":"Sensors"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1012","DOI":"10.3390\/mi5041012","article-title":"A Particle Filter for Smartphone-Based Indoor Pedestrian Navigation","volume":"5","author":"Masiero","year":"2014","journal-title":"Micromachines"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1109\/MSP.2005.1458289","article-title":"Localization via ultra-wideband radios: A look at positioning aspects for future sensor networks","volume":"22","author":"Gezici","year":"2005","journal-title":"IEEE Signal Process. Mag."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Sahinoglu, Z., Gezici, S., and Guvenc, I. (2008). Ultra-Wideband Positioning Systems, Cambridge University Press.","DOI":"10.1017\/CBO9780511541056"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Hol, J.D., Sch\u00f6n, T.B., and Gustafsson, F. (2010, January 20\u201323). Ultra-wideband calibration for indoor positioning. Proceedings of the IEEE International Conference on Ultra-Wideband, Nanjing, China.","DOI":"10.1109\/ICUWB.2010.5616867"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Merkl, B., Fathy, A., and Mahfouz, M. (2008, January 10\u201312). Base Station Orientation Calibration in 3-D Indoor UWB Positioning. Proceedings of the 2008 IEEE International Conference on Ultra-Wideband, Hannover, Germany.","DOI":"10.1109\/ICUWB.2008.4653292"},{"key":"ref_22","unstructured":"(2017, April 24). Pozyx Labs, Pozyx Positioning System. Available online: https:\/\/www.pozyx.io\/."},{"key":"ref_23","first-page":"1345","article-title":"Analysis of glacial and periglacial processes using structure from motion","volume":"3","author":"Piermattei","year":"2015","journal-title":"Earth Surf. Dyn. Discuss."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1891","DOI":"10.1002\/esp.3767","article-title":"Bank erosion in agricultural drainage networks: New challenges from structure-from-motion photogrammetry for post-event analysis","volume":"40","author":"Prosdocimi","year":"2015","journal-title":"Earth Surf. Process. Landf."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"487","DOI":"10.5194\/isprsarchives-XXXIX-B7-487-2012","article-title":"Direct georeferencing with on board navigation components of light weight UAV platforms","volume":"XXXIX-B7","author":"Pfeifer","year":"2012","journal-title":"Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"9161","DOI":"10.3390\/s120709161","article-title":"The development of an UAV borne direct georeferenced photogrammetric platform for ground control point free applications","volume":"12","author":"Chiang","year":"2012","journal-title":"Sensors"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2738","DOI":"10.1109\/TGRS.2013.2265295","article-title":"Direct georeferencing of ultrahigh-resolution UAV imagery","volume":"52","author":"Turner","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"151","DOI":"10.5194\/isprsarchives-XL-1-W4-151-2015","article-title":"The Direct Georeferencing Application and Performance Analysis of UAV Helicopter in GCP-Free Area","volume":"40","author":"Lo","year":"2015","journal-title":"Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"380","DOI":"10.1016\/j.ifacol.2015.07.064","article-title":"The Use of Direct Georeferencing in Aerial Photogrammetry with Micro UAV","volume":"48","author":"Gabrlik","year":"2015","journal-title":"IFAC-PapersOnLine"},{"key":"ref_30","first-page":"198","article-title":"Direct georeferencing using GPS\/inertial exterior orientations for photogrammetric applications","volume":"33","author":"Cramer","year":"2000","journal-title":"Int. Arch. Photogramm. Remote Sens."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"5005","DOI":"10.1029\/96JB03860","article-title":"Precise point positioning for the efficient and robust analysis of GPS data from large networks","volume":"102","author":"Zumberge","year":"1997","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/S0924-2716(97)00005-1","article-title":"Digital camera self-calibration","volume":"52","author":"Fraser","year":"1997","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"948","DOI":"10.1117\/1.1555732","article-title":"Automatic calibration of low-cost digital cameras","volume":"42","author":"Habib","year":"2003","journal-title":"Opt. Eng."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.isprsjprs.2015.10.006","article-title":"Sensor modelling and camera calibration for close-range photogrammetry","volume":"115","author":"Luhmann","year":"2015","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"17471","DOI":"10.3390\/s140917471","article-title":"Calibration of Action Cameras for Photogrammetric Purposes","volume":"14","author":"Balletti","year":"2014","journal-title":"Sensors"},{"key":"ref_36","first-page":"855","article-title":"Close-range camera calibration","volume":"37","author":"Brown","year":"1971","journal-title":"Photogramm. Eng."},{"key":"ref_37","unstructured":"(1970, January 01). Agisoft PhotoScan. Available online: http:\/\/www.agisoft.com\/."},{"key":"ref_38","unstructured":"Li, Z., Trappe, W., Zhang, Y., and Nath, B. (2005, January 25\u201327). Robust Statistical Methods for Securing Wireless Localization in Sensor Networks. Proceedings of the 4th International Symposium on Information Processing in Sensor Networks, Los Angeles, CA, USA."},{"key":"ref_39","unstructured":"Bertinato, M., Ortolan, G., Maran, F., Marcon, R., Marcassa, A., Zanella, F., Zambotto, M., Schenato, L., and Cenedese, A. (2008). RF Localization and Tracking of Mobile Nodes in Wireless Sensors Networks: Architectures, Algorithms and Experiments, University of Padova. Technical Report."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"5450","DOI":"10.1109\/TVT.2015.2481509","article-title":"GNSS Multipath-Resistant Cooperative Navigation in Urban Vehicular Networks","volume":"64","author":"Ko","year":"2015","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"219","DOI":"10.5194\/isprsarchives-XL-1-W4-219-2015","article-title":"UAV Positioning and Collision Avoidance Based on RSS Measurements","volume":"40","author":"Masiero","year":"2015","journal-title":"Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_42","unstructured":"Anderson, B.D., and Moore, J.B. (2012). Optimal Filtering, Courier Corporation."},{"key":"ref_43","unstructured":"Jazwinski, A.H. (2007). Stochastic Processes and Filtering Theory, Courier Corporation."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1017\/S0373463309990142","article-title":"A comparison of outlier detection procedures and robust estimation methods in GPS positioning","volume":"62","author":"Knight","year":"2009","journal-title":"J. Navig."},{"key":"ref_45","doi-asserted-by":"crossref","unstructured":"F\u00f6rstner, W., and Wrobel, B.P. (2016). Photogrammetric Computer Vision, Springer.","DOI":"10.1007\/978-3-319-11550-4"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Hartley, R., and Zisserman, A. (2003). Multiple View Geometry in Computer Vision, Cambridge University Press.","DOI":"10.1017\/CBO9780511811685"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Ma, Y., Soatto, S., Kosecka, J., and Sastry, S. (2004). An Invitation to 3-D Vision: From Images to Geometric Models, Interdisciplinary Applied Mathematics: Imaging, Vision, and Graphics, Springer.","DOI":"10.1007\/978-0-387-21779-6"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/j.imavis.2012.02.009","article-title":"Visual SLAM: why filter?","volume":"30","author":"Strasdat","year":"2012","journal-title":"Image Vis. Comput."},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Lowe, D. (1999, January 20\u201327). Object Recognition from Local Scale-Invariant Features. Proceedings of the Seventh IEEE International Conference on Computer Vision, Kerkyra, Greece.","DOI":"10.1109\/ICCV.1999.790410"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Leutenegger, S., Chli, M., and Siegwart, R.Y. (2011, January 6\u201313). BRISK: Binary Robust Invariant Scalable Keypoints. Proceedings of the 2011 IEEE International Conference on Computer Vision (ICCV), Barcelona, Spain.","DOI":"10.1109\/ICCV.2011.6126542"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"3745","DOI":"10.3390\/s90503745","article-title":"Performance analysis of the SIFT operator for automatic feature extraction and matching in photogrammetric applications","volume":"9","author":"Lingua","year":"2009","journal-title":"Sensors"},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Masiero, A., and Vettore, A. (2016). Improved Feature Matching for Mobile Devices with IMU. Sensors, 16.","DOI":"10.3390\/s16081243"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1109\/34.134043","article-title":"Fitting parameterized three-dimensional models to images","volume":"13","author":"Lowe","year":"1991","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1016\/j.isprsjprs.2016.11.009","article-title":"Time synchronization of consumer cameras on Micro Aerial Vehicles","volume":"123","author":"Rehak","year":"2017","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_55","unstructured":"Rothermel, M., Wenzel, K., Fritsch, D., and Haala, N. (2012, January 4\u20135). SURE: Photogrammetric Surface Reconstruction from Imagery. Proceedings of the LC3D Workshop, Berlin, Germany."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1109\/TPAMI.2007.1166","article-title":"Stereo processing by semiglobal matching and mutual information","volume":"30","author":"Hirschmuller","year":"2008","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/5\/414\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:34:00Z","timestamp":1760207640000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/5\/414"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,4,27]]},"references-count":56,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2017,5]]}},"alternative-id":["rs9050414"],"URL":"https:\/\/doi.org\/10.3390\/rs9050414","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,4,27]]}}}