{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T08:17:07Z","timestamp":1761293827861,"version":"build-2065373602"},"reference-count":47,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,10,25]],"date-time":"2018-10-25T00:00:00Z","timestamp":1540425600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["642332"],"award-info":[{"award-number":["642332"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Road traffic and its impacts affect various aspects of wellbeing with safety, congestion and pollution being of significant concern in cities. Although there have been a large number of works done in the field of traffic data collection, there are several barriers which restrict the collection of traffic data at higher resolution in the cities. Installation and maintenance costs can act as a disincentive to use existing methods (e.g., loop detectors, video analysis) at a large scale and hence limit their deployment to only a few roads of the city. This paper presents an approach for vehicle counting using a low cost, simple and easily installable system. In the proposed system, vehicles (i.e., bicycles, cars, trucks) are counted by means of variations in the WiFi signals. Experiments with the developed hardware in two different scenarios\u2014low traffic (i.e., 400 objects) and heavy traffic roads (i.e., 1000 objects)\u2014demonstrate its ability to detect cars and trucks. The system can be used to provide estimates of vehicle numbers for streets not covered by official traffic monitoring techniques in future smart cities.<\/jats:p>","DOI":"10.3390\/s18113623","type":"journal-article","created":{"date-parts":[[2018,10,26]],"date-time":"2018-10-26T03:16:16Z","timestamp":1540523776000},"page":"3623","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Low-Cost Open Hardware System for Collecting Traffic Data Using Wi-Fi Signal Strength"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1450-5435","authenticated-orcid":false,"given":"Shivam","family":"Gupta","sequence":"first","affiliation":[{"name":"Institute For Geoinformatics, Westf\u00e4lische Wilhelms-Universit\u00e4t, 48149 M\u00fcnster, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6096-4707","authenticated-orcid":false,"given":"Albert","family":"Hamzin","sequence":"additional","affiliation":[{"name":"Institute For Geoinformatics, Westf\u00e4lische Wilhelms-Universit\u00e4t, 48149 M\u00fcnster, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5087-8776","authenticated-orcid":false,"given":"Auriol","family":"Degbelo","sequence":"additional","affiliation":[{"name":"Institute For Geoinformatics, Westf\u00e4lische Wilhelms-Universit\u00e4t, 48149 M\u00fcnster, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Lord, D., and Washington, S. (2018). Introduction. Safe Mobility: Challenges, Methodology and Solutions, Emerald Publishing Limited.","DOI":"10.1108\/S2044-9941201811"},{"key":"ref_2","unstructured":"Birgitta, B., Thomas, L., and Dietrich, H. (1999). Guidelines for community noise. The WHO Expert Task Force Meeting on Guidelines for Community Noise, WHO."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2290","DOI":"10.1093\/eurheartj\/ehx263","article-title":"Long-term exposure to road traffic noise, ambient air pollution, and cardiovascular risk factors in the HUNT and lifelines cohorts","volume":"38","author":"Cai","year":"2017","journal-title":"Eur. Heart J."},{"key":"ref_4","first-page":"1","article-title":"Quantify Effects of Traffic, Grasslands and Water Bodies on Urban Heat Islands: Kent Vale Case Study","volume":"1","author":"Xu","year":"2017","journal-title":"J. Environ. Bio Res."},{"key":"ref_5","unstructured":"Agency, E.E. (2018, August 18). Air Pollution Sources. Available online: https:\/\/www.eea.europa.eu\/themes\/air\/air-pollution-sources."},{"key":"ref_6","unstructured":"Mertens, M., Kerkweg, A., Grewe, V., and J\u00f6ckel, P. (2016, January 17\u201322). Impact of road traffic emissions on tropospheric ozone in Europe for present day and future scenarios. Proceedings of the 2016 EGU General Assembly Conference, Vienna, Austria."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1097\/EDE.0000000000000555","article-title":"Impact of road traffic pollution on pre-eclampsia and pregnancy-induced hypertensive disorders","volume":"28","author":"Pedersen","year":"2017","journal-title":"Epidemiology (Camb. MA)"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.envres.2017.03.019","article-title":"Long-term residential road traffic noise and NO2 exposure in relation to risk of incident myocardial infarction\u2014A Danish cohort study","volume":"156","author":"Roswall","year":"2017","journal-title":"Environ. Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/j.envres.2017.10.002","article-title":"Land use regression models for the oxidative potential of fine particles (PM 2.5) in five European areas","volume":"160","author":"Gulliver","year":"2018","journal-title":"Environ. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"775","DOI":"10.1016\/j.envpol.2018.06.019","article-title":"Review of modelling air pollution from traffic at street-level-The state of the science","volume":"241","author":"Forehead","year":"2018","journal-title":"Environ. Pollut."},{"key":"ref_11","unstructured":"Polk, A., Kranig, J., and Minge, E. (1996). Field test of non-intrusive traffic detection technologies. Intelligent Transportation: Realizing the Benefits. Proceedings of the 1996 Annual Meeting of ITS America, ITS America."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"809","DOI":"10.1016\/j.trd.2018.06.026","article-title":"A practical model for predicting road traffic carbon dioxide emissions using Inductive Loop Detector data","volume":"63","author":"Grote","year":"2018","journal-title":"Transp. Res. Part D Transp. Environ."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"393","DOI":"10.3390\/s130100393","article-title":"The role of advanced sensing in smart cities","volume":"13","author":"Hancke","year":"2013","journal-title":"Sensors"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Degbelo, A., Granell, C., Trilles, S., Bhattacharya, D., Casteleyn, S., and Kray, C. (2016). Opening up smart cities: Citizen-centric challenges and opportunities from GIScience. ISPRS Int. J. Geo-Inf., 5.","DOI":"10.3390\/ijgi5020016"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Nellore, K., and Hancke, G. (2016). A survey on urban traffic management system using wireless sensor networks. Sensors, 16.","DOI":"10.3390\/s16020157"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"98","DOI":"10.3141\/1804-14","article-title":"Real-time traffic measurement from single loop inductive signatures","volume":"1804","author":"Oh","year":"2002","journal-title":"Transp. Res. Rec. J. Transp. Res. Board"},{"key":"ref_17","unstructured":"Mimbela, L.E.Y., and Klein, L.A. (2000). Summary of Vehicle Detection and Surveillance Technologies Used in Intelligent Transportation Systems, Federal Highway Administration, Intelligent Transportation Systems Joint Program Office."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1784","DOI":"10.1109\/TITS.2017.2741507","article-title":"Intelligent Vehicle Counting and Classification Sensor for Real-Time Traffic Surveillance","volume":"19","author":"Balid","year":"2018","journal-title":"IEEE Trans. Intell. Transp. Syst."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"920","DOI":"10.1109\/TITS.2011.2119372","article-title":"A review of computer vision techniques for the analysis of urban traffic","volume":"12","author":"Buch","year":"2011","journal-title":"IEEE Trans. Intell. Transp. Syst."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5817","DOI":"10.1007\/s11042-015-2520-x","article-title":"Vehicle detection and recognition for intelligent traffic surveillance system","volume":"76","author":"Tang","year":"2017","journal-title":"Multimed. Tools Appl."},{"key":"ref_21","unstructured":"Martin, P.T., Feng, Y., and Wang, X. (2003). Detector Technology Evaluation, Utah Department of Transportation, Research Division. Technical Report."},{"key":"ref_22","unstructured":"Cheung, S.Y., and Varaiya, P.P. (2006). Traffic Surveillance by Wireless Sensor Networks. [Ph.D. Thesis, University of California]."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"4455","DOI":"10.1098\/rsta.2010.0205","article-title":"Traffic jams: Dynamics and control","volume":"368","author":"Orosz","year":"2010","journal-title":"Philos. Trans. R. Soc. A Math. Phys. Eng. Sci."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1016\/j.trc.2007.10.004","article-title":"Wireless magnetic sensors for traffic surveillance","volume":"16","author":"Haoui","year":"2008","journal-title":"Transp. Res. Part C Emerg. Technol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Fang, J., Meng, H., Zhang, H., and Wang, X. (October, January 30). A low-cost vehicle detection and classification system based on unmodulated continuous-wave radar. Proceedings of the ITSC 2007 Intelligent Transportation Systems Conference, Seattle, WA, USA.","DOI":"10.1109\/ITSC.2007.4357739"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"741","DOI":"10.1007\/s11554-014-0411-4","article-title":"A low-cost vehicle counter for next-generation ITS","volume":"10","author":"Salvadori","year":"2015","journal-title":"J. Real-Time Image Process."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1381","DOI":"10.1109\/JSAC.2015.2430272","article-title":"Occupancy estimation using only WiFi power measurements","volume":"33","author":"Depatla","year":"2015","journal-title":"IEEE J. Sel. Areas Commun."},{"key":"ref_28","unstructured":"Wang, Y., Yang, J., Liu, H., Chen, Y., Gruteser, M., and Martin, R.P. (October, January 30). Measuring human queues using WiFi signals. Proceedings of the 19th Annual International Conference on Mobile Computing & Networking, Miami, FL, USA."},{"key":"ref_29","unstructured":"Hong, F., Wang, X., Yang, Y., Zong, Y., Zhang, Y., and Guo, Z. (December, January 28). WFID: Passive device-free human identification using WiFi signal. Proceedings of the 13th International Conference on Mobile and Ubiquitous Systems: Computing, Networking and Services, Hiroshima, Japan."},{"key":"ref_30","unstructured":"Pu, Q., Gupta, S., Gollakota, S., and Patel, S. (October, January 30). Whole-home gesture recognition using wireless signals. Proceedings of the 19th Annual International Conference on Mobile Computing & Networking, Miami, FL, USA."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Won, M., Zhang, S., and Son, S.H. (August, January 31). WiTraffic: Low-cost and non-intrusive traffic monitoring system using WiFi. Proceedings of the 2017 26th International Conference on Computer Communication and Networks (ICCCN), Vancouver, BC, Canada.","DOI":"10.1109\/ICCCN.2017.8038380"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Roy, S., Sen, R., Kulkarni, S., Kulkarni, P., Raman, B., and Singh, L.K. (2011, January 4\u20138). Wireless across road: RF based road traffic congestion detection. Proceedings of the 2011 Third International Conference on Communication Systems and Networks (COMSNETS), Bangalore, India.","DOI":"10.1109\/COMSNETS.2011.5716525"},{"key":"ref_33","unstructured":"Horvat, G., \u0160o\u0161tari\u0107, D., and \u017dagar, D. (2012, January 21\u201325). Using radio irregularity for vehicle detection in adaptive roadway lighting. Proceedings of the MIPRO 2012: 35th International Convention, Opatija, Croatia."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Haferkamp, M., Al-Askary, M., Dorn, D., Sliwa, B., Habel, L., Schreckenberg, M., and Wietfeld, C. (2017, January 4\u20137). Radio-based traffic flow detection and vehicle classification for future smart cities. Proceedings of the 2017 IEEE 85th Vehicular Technology Conference (VTC Spring), Sydney, Australia.","DOI":"10.1109\/VTCSpring.2017.8108633"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"3251598","DOI":"10.1155\/2018\/3251598","article-title":"Road Traffic Monitoring System Based on Mobile Devices and Bluetooth Low Energy Beacons","volume":"2018","author":"Lewandowski","year":"2018","journal-title":"Wirel. Commun. Mob. Comput."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1669","DOI":"10.1109\/JSEN.2010.2103937","article-title":"Wireless magnetic sensor node for vehicle detection with optical wake-up","volume":"11","author":"Sifuentes","year":"2011","journal-title":"IEEE Sens. J."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1109\/MIS.2013.56","article-title":"A lightweight conditional privacy-preservation protocol for vehicular traffic-monitoring systems","volume":"28","author":"Lu","year":"2013","journal-title":"IEEE Intell. Syst."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"849","DOI":"10.1109\/TMC.2011.116","article-title":"Enhancing Privacy and Accuracy in Probe Vehicle-Based Traffic Monitoring via Virtual Trip Lines","volume":"11","author":"Hoh","year":"2012","journal-title":"IEEE Trans. Mob. Comput."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Yang, C., Qin, B., Zhou, X., Sun, Y., He, S., and Wu, Q. (2015, January 25\u201327). Privacy-Preserving Traffic Monitoring in Vehicular Ad Hoc Networks. Proceedings of the 2015 IEEE 29th International Conference on Advanced Information Networking and Applications Workshops (WAINA), Gwangju, Korea.","DOI":"10.1109\/WAINA.2015.31"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Cote, M., and Albu, A.B. (2017, January 21\u201326). Teaching Computer Vision and Its Societal Effects: A Look at Privacy and Security Issues From the Students\u2019 Perspective. Proceedings of the 2017 IEEE Conference on Computer Vision and Pattern Recognition Workshops (CVPRW), Honolulu, HI, USA.","DOI":"10.1109\/CVPRW.2017.180"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Lu, R., Lin, X., Zhu, H., Ho, P.H., and Shen, X. (2008, January 13\u201318). ECPP: Efficient conditional privacy preservation protocol for secure vehicular communications. Proceedings of the INFOCOM 2008: 27th Conference on Computer Communications, Phoenix, AZ, USA.","DOI":"10.1109\/INFOCOM.2008.179"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"3442","DOI":"10.1109\/TVT.2007.906878","article-title":"GSIS: A secure and privacy-preserving protocol for vehicular communications","volume":"56","author":"Lin","year":"2007","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"39","DOI":"10.3233\/JCS-2007-15103","article-title":"Securing vehicular ad hoc networks","volume":"15","author":"Raya","year":"2007","journal-title":"J. Comput. Secur."},{"key":"ref_44","unstructured":"Gupta, S. (2018, August 27). WiFi-Traffic-Videotool. Available online: https:\/\/github.com\/Albertios\/Bachelor-Thesis."},{"key":"ref_45","unstructured":"European Commission (2018, August 19). Free Wireless Internet Hotspots in Public Spaces. Available online: https:\/\/ec.europa.eu\/commission\/news\/free-wireless-internet-hotspots-public-spaces-2018-mar-20_en."},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Ho, T.J., and Chung, M.J. (2016, January 26\u201330). An approach to traffic flow detection improvements of non-contact microwave radar detectors. Proceedings of the 2016 International Conference on Applied System Innovation (ICASI), Okinawa, Japan.","DOI":"10.1109\/ICASI.2016.7539785"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"694545","DOI":"10.1155\/2014\/694545","article-title":"An intelligent traffic flow control system based on radio frequency identification and wireless sensor networks","volume":"10","author":"Chao","year":"2014","journal-title":"Int. J. Distrib. Sens. Netw."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/11\/3623\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:26:09Z","timestamp":1760196369000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/11\/3623"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,10,25]]},"references-count":47,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2018,11]]}},"alternative-id":["s18113623"],"URL":"https:\/\/doi.org\/10.3390\/s18113623","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2018,10,25]]}}}