{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T11:52:00Z","timestamp":1777981920054,"version":"3.51.4"},"reference-count":26,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2019,7,22]],"date-time":"2019-07-22T00:00:00Z","timestamp":1563753600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2017R1D1A1B03029992"],"award-info":[{"award-number":["2017R1D1A1B03029992"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002613","name":"Ulsan National Institute of Science and Technology","doi-asserted-by":"publisher","award":["1.190011.01"],"award-info":[{"award-number":["1.190011.01"]}],"id":[{"id":"10.13039\/501100002613","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a detailed experimental assessment of Gaussian Process (GP) regression for air-to-ground communication channel prediction for relay missions in urban environment. Considering restrictions from outdoor urban flight experiments, a way to simulate complex urban environments at an indoor room scale is introduced. Since water significantly absorbs wireless communication signal, water containers are utilized to replace buildings in a real-world city. To evaluate the performance of the GP-based channel prediction approach, several indoor experiments in an artificial urban environment were conducted. The performance of the GP-based and empirical model-based prediction methods for a relay mission was evaluated by measuring and comparing the communication signal strength at the optimal relay position obtained from each method. The GP-based prediction approach shows an advantage over the model-based one as it provides a reasonable performance without a need for a priori information of the environment (e.g., 3D map of the city and communication model parameters) in dynamic urban environments.<\/jats:p>","DOI":"10.3390\/s19143221","type":"journal-article","created":{"date-parts":[[2019,7,22]],"date-time":"2019-07-22T11:07:28Z","timestamp":1563793648000},"page":"3221","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Experimental Validation of Gaussian Process-Based Air-to-Ground Communication Quality Prediction in Urban Environments"],"prefix":"10.3390","volume":"19","author":[{"given":"Pawel","family":"Ladosz","sequence":"first","affiliation":[{"name":"Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jongyun","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Mechanical, Aerospace and Nuclear Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1051-9477","authenticated-orcid":false,"given":"Hyondong","family":"Oh","sequence":"additional","affiliation":[{"name":"School of Mechanical, Aerospace and Nuclear Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wen-Hua","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,22]]},"reference":[{"key":"ref_1","unstructured":"Shin, H.S., and Segui Gasco, P. (2016). UAV swarms: Decision-making paradigms. Encyclopedia of Aerospace Engineering, John Wiley & Sons, Ltd."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Ho, D.T., Gr\u00f8tli, E.I., Sujit, P., Johansen, T.A., and De Sousa, J.B. (2013, January 9\u201313). Performance evaluation of cooperative relay and particle swarm optimization path planning for UAV and wireless sensor network. Proceedings of the IEEE Globecom Workshops (GC Wkshps), Atlanta, GA, USA.","DOI":"10.1109\/GLOCOMW.2013.6825191"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.conengprac.2014.04.003","article-title":"Coordinated trajectory planning for efficient communication relay using multiple UAVs","volume":"29","author":"Kim","year":"2014","journal-title":"Control. Eng. Pract."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"498","DOI":"10.1109\/LCOMM.2019.2894696","article-title":"Joint Blocklength and Location Optimization for URLLC-Enabled UAV Relay Systems","volume":"23","author":"Pan","year":"2019","journal-title":"IEEE Commun. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"883","DOI":"10.1109\/JSAC.2012.120605","article-title":"Optimizing cascaded chains of unmanned aircraft acting as communication relays","volume":"30","author":"Dixon","year":"2012","journal-title":"IEEE J. Sel. Areas Commun."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"101","DOI":"10.5772\/10577","article-title":"Hybrid control of long-endurance aerial robotic vehicles for wireless sensor networks","volume":"8","author":"Lee","year":"2011","journal-title":"Int. J. Adv. Robot. Syst."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Carfang, A.J., Wagle, N., and Frew, E.W. (2014, January 14\u201318). Improving data ferrying by iteratively learning the radio frequency environment. Proceedings of the IEEE\/RSJ International Conference on Intelligent Robots and Systems (IROS), Chicago, IL, USA.","DOI":"10.1109\/IROS.2014.6942707"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Chen, J., Yatnalli, U., and Gesbert, D. (2017, January 21\u201325). Learning radio maps for UAV-aided wireless networks: A segmented regression approach. Proceedings of the 2017 IEEE International Conference on Communications (ICC), Paris, France.","DOI":"10.1109\/ICC.2017.7997333"},{"key":"ref_9","unstructured":"Watza, S., Kanlapuli, R., and Frew, E. (2017, January 12\u201316). Hybrid RF Propagation Model using ITM and Gaussian processes for Communication-Aware Planning. Proceedings of the Robotics: Science and Systems XIII, Cambridge, MA, USA."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Fink, J., Michael, N., Kushleyev, A., and Kumar, V. (2009, January 11\u201315). Experimental characterization of radio signal propagation in indoor environments with application to estimation and control. Proceedings of the IEEE\/RSJ International Conference on Intelligent Robots and Systems, St. Louis, MO, USA.","DOI":"10.1109\/IROS.2009.5354194"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2532","DOI":"10.1109\/TMECH.2017.2751149","article-title":"Autonomous Wi-Fi Relay Placement With Mobile Robots","volume":"22","author":"Gao","year":"2017","journal-title":"IEEE\/ASME Trans. Mechatron."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Caccamo, S., Parasuraman, R., Freda, L., Gianni, M., and \u00d6gren, P. (2017, January 24\u201328). RCAMP: A resilient communication-aware motion planner for mobile robots with autonomous repair of wireless connectivity. Proceedings of the 2017 IEEE\/RSJ International Conference on Intelligent Robots and Systems (IROS), Vancouver, BC, Canada.","DOI":"10.1109\/IROS.2017.8206020"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Ladosz, P., Oh, H., and Chen, W.H. (2017, January 24\u201328). Prediction of air-to-ground communication strength for relay UAV trajectory planner in urban environments. Proceedings of the IEEE\/RSJ International Conference on Intelligent Robots and Systems (IROS), Vancouver, BC, Canada.","DOI":"10.1109\/IROS.2017.8206603"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Ladosz, P., Oh, H., Zheng, G., and Chen, W. (2019). Gaussian Process-Based Channel Prediction for Communication Relay UAV in Urban Environments. IEEE Trans. Aerosp. Electron. Syst., in press.","DOI":"10.1109\/TAES.2019.2917989"},{"key":"ref_15","unstructured":"Meador, B. (2019, June 30). A Survey of Computer Network Topology and Analysis Examples. Available online: https:\/\/www.cse.wustl.edu\/~jain\/cse567-08\/ftp\/topology\/index.html."},{"key":"ref_16","unstructured":"Paciorek, C.J., and Schervish, M.J. (2004). Nonstationary covariance functions for Gaussian process regression. Advances in Neural Information Processing Systems, MIT Press."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Qureshi, U.M., Shaikh, F.K., Aziz, Z., Shah, S.M.Z.S., Sheikh, A.A., Felemban, E., and Qaisar, S.B. (2016). RF path and absorption loss estimation for underwater wireless sensor networks in different water environments. Sensors, 16.","DOI":"10.3390\/s16060890"},{"key":"ref_18","unstructured":"Open Mesh.net, B.A.T.M.A.N (2019, June 28). (Better Approach to Mobile Ad-Hoc Networking). Available online: http:\/\/www.open-mesh.net\/."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1109\/MWC.2010.5416357","article-title":"IEEE 802.11 s: The WLAN Mesh Standard","volume":"17","author":"Hiertz","year":"2010","journal-title":"IEEE Wirel. Commun."},{"key":"ref_20","unstructured":"IEEE 802 LAN\/MAN Standards Committee (2019, June 28). IEEE Standard for Low-Rate Wireless Networks\u2014Amendment 5: Enabling\/Updating the Use of Regional Sub-GHz Bands. Available online: https:\/\/ieeexplore.ieee.org\/document\/7964803."},{"key":"ref_21","unstructured":"Voinov, I.A., Cede\u00f1o, A.C., Chung, J., and Gonz\u00e1lez, G. (2014, January 6\u20139). A Performance Analysis of Wireless Mesh Networks Implementations Based on Open Source Software. Proceedings of the IFIP International Conference on Open Source Systems, San Jose, Costa Rica."},{"key":"ref_22","unstructured":"Stambler, A. (2019, June 28). rosserial_xbee. Available online: http:\/\/wiki.ros.org\/rosserial_xbee."},{"key":"ref_23","unstructured":"Ermakov, V. (2019, June 28). mavros. Available online: http:\/\/wiki.ros.org\/mavros."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Ladosz, P., Coombes, M., Smith, J., and Hutchinson, M. (2019). A generic ROS based system for rapid development and testing of algorithms for autonomous ground and aerial vehicles. Robot Operating System (ROS), Springer.","DOI":"10.1007\/978-3-319-91590-6_4"},{"key":"ref_25","first-page":"3011","article-title":"Gaussian processes for machine learning (GPML) toolbox","volume":"11","author":"Rasmussen","year":"2010","journal-title":"J. Mach. Learn. Res."},{"key":"ref_26","unstructured":"Rasmussen, C.E., and Ghahramani, Z. (2002). Infinite mixtures of Gaussian process experts. Advances in Neural Information Processing Systems, MIT Press."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/14\/3221\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:08:20Z","timestamp":1760188100000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/14\/3221"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,7,22]]},"references-count":26,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2019,7]]}},"alternative-id":["s19143221"],"URL":"https:\/\/doi.org\/10.3390\/s19143221","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,7,22]]}}}