{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:27:17Z","timestamp":1760243237826,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2014,12,12]],"date-time":"2014-12-12T00:00:00Z","timestamp":1418342400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, the characterization of the radio channel for ISM 2.4GHz Wireless Sensor Networks (WSNs) for judo applications is presented. The environments where judo activity is held are usually complex indoor scenarios in terms of radiopropagation due to their morphology, the presence of humans and the electromagnetic interference generated by personal portable devices, wireless microphones and other wireless systems used by the media. For the assessment of the impact that the topology and the morphology of these environments have on electromagnetic propagation, an in-house developed 3D ray-launching software has been used in this study. Time domain results as well as estimations of received power level have been obtained for the complete volume of a training venue of a local judo club\u2019s facilities with a contest area with the dimensions specified by the International Judo Federation (IJF) for international competitions. The obtained simulation results have been compared with measurements, which have been carried out deploying ZigBee-compliant XBee Pro modules at presented scenario, using approved Judogis (jacket, trousers and belt). The analysis is completed with the inclusion of an in-house human body computational model. Such analysis has allowed the design and development of an in house application devoted to monitor the practice of judo, in order to aid referee activities, training routines and to enhance spectator experience.<\/jats:p>","DOI":"10.3390\/s141224004","type":"journal-article","created":{"date-parts":[[2014,12,12]],"date-time":"2014-12-12T10:06:43Z","timestamp":1418378803000},"page":"24004-24028","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Radio Characterization for ISM 2.4 GHz Wireless Sensor Networks for Judo Monitoring Applications"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8411-1928","authenticated-orcid":false,"given":"Peio","family":"Lopez-Iturri","sequence":"first","affiliation":[{"name":"Electrical and Electronic Engineering Department, Public University of Navarre, Pamplona 31006, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erik","family":"Aguirre","sequence":"additional","affiliation":[{"name":"Electrical and Electronic Engineering Department, Public University of Navarre, Pamplona 31006, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leire","family":"Azpilicueta","sequence":"additional","affiliation":[{"name":"Electrical and Electronic Engineering Department, Public University of Navarre, Pamplona 31006, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7792-6317","authenticated-orcid":false,"given":"Jos\u00e9","family":"Astrain","sequence":"additional","affiliation":[{"name":"Computer and Mathematics Engineering Department, Public University of Navarre,  Pamplona 31006, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7341-9529","authenticated-orcid":false,"given":"Jes\u00fas","family":"Villadangos","sequence":"additional","affiliation":[{"name":"Computer and Mathematics Engineering Department, Public University of Navarre,  Pamplona 31006, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4911-9753","authenticated-orcid":false,"given":"Francisco","family":"Falcone","sequence":"additional","affiliation":[{"name":"Electrical and Electronic Engineering Department, Public University of Navarre, Pamplona 31006, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2014,12,12]]},"reference":[{"key":"ref_1","unstructured":"Zhong, X., Chan, H.-H., Rogers, T.J., Rosenberg, C.P., and Coyle, E.J. (2006, January 1\u20133). The development and eStadium testbeds for research and development of wireless services for large-scale sports venues. Barcelona, Spain."},{"key":"ref_2","unstructured":"Chen, C., Wei, B., and Zhang, F. (2011, January 20\u201321). Design and realization of wireless environmental monitoring system based on ZigBee for stadium. Xi'an, China."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1109\/MPRV.2005.67","article-title":"Introducing wearable force sensors in martial arts","volume":"4","author":"Chi","year":"2005","journal-title":"IEEE Pervasive Comput."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Yin, Z., Ning, H., Inoue, Y., Han, M., and Liu, T. (2013, January 3\u20136). A Novel Wireless Motion Sensor for analyzing Golf Swing. Baltimore, MD, USA.","DOI":"10.1109\/ICSENS.2013.6688446"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Heinz, E.A., Kunze, K.S., Gruber, M., Bannach, D., and Lukowicz, P. (2006, January 22\u201324). Using Wearable Sensors for Real-Time Recognition Tasks in Games of Martial Arts - An Initial Experiment. Reno, NV, USA.","DOI":"10.1109\/CIG.2006.311687"},{"key":"ref_6","unstructured":"Cheng, L., and Hailes, S. (December, January 30). Analysis of Wireless Inertial Sensing for Athlete Coaching Support. New Orleans, LO, USA."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Wei, P., Morey, B., Dyson, T., McMahon, N., Hsu, Y.-Y., Gazman, S., Klinker, L., Ives, B., Dowling, K., and Rafferty, C. (2013, January 3\u20136). A conformal sensor for wireless sweat level monitoring. Baltimore, MD, USA.","DOI":"10.1109\/ICSENS.2013.6688376"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Kuznietsov, A., and Neubauer, D. (2012, January 20\u201323). A wireless framework for movement activity monitoring of sprinters. Chemnitz, Germany.","DOI":"10.1109\/SSD.2012.6198028"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Stamm, A., James, D.A., Hagem, R.M., and Thiel, D.V. (2012, January 28\u201331). Investigating arm symmetry in swimming using inertial sensors. Taipei, China.","DOI":"10.1109\/ICSENS.2012.6411436"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1109\/TSMC.2012.2235428","article-title":"Design and Implementation of an Integrated Performance Monitoring Tool for Swimming to Extract Stroke Information at Real Time","volume":"43","author":"Chakravorti","year":"2013","journal-title":"IEEE Trans. Human-Machine Syst."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Vales-Alonso, J., Lopez-Matencio, P., Veiga-Gontan, J., Banos Guirao, P., and Alcaraz, J.J. (2013, January 6\u20138). An effort control system for training elite team-sport athletes. Sopot, Poland.","DOI":"10.1109\/HSI.2013.6577836"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2864","DOI":"10.1109\/JSEN.2014.2318897","article-title":"A Novel Complimentary Filter for Tracking Hip Angles During Cycling Using Wireless Inertial Sensors and Dynamic Acceleration Estimation","volume":"14","author":"Cockcroft","year":"2014","journal-title":"IEEE Sens. J."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"16065","DOI":"10.3390\/s131216065","article-title":"Detection of Illegal Race Walking: A Tool to Assist Coaching and Judging","volume":"13","author":"Lee","year":"2013","journal-title":"Sensors"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Rowlands, D.D., McNab, T., Laakso, L., and James, D.A. (2012, January 10\u201315). Cloud based activity monitoring system for health and sport. Brisbane, Australia.","DOI":"10.1109\/IJCNN.2012.6252502"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2359","DOI":"10.3390\/s100302359","article-title":"Ambient Intelligence Systems for Personalized Sport Training","volume":"10","year":"2010","journal-title":"Sensors"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1787","DOI":"10.3390\/s130201787","article-title":"Combining Wireless Sensor Networks and Semantic Middleware for an Internet of Things-Based Sportsman\/Woman Monitoring Application","volume":"13","author":"Castillejo","year":"2013","journal-title":"Sensors"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Wada, S., Fukase, M., Nakanishi, Y., and Tatsuta, L. (2013, January 23\u201325). In search of a usability of Kinect in the training of traditional Japanese \u201cKATA\u201d \u2014Stylized gestures and movements. Lodz, Poland.","DOI":"10.1109\/ICeLeTE.2013.6644369"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Ambekar, D., Al-Deneh, Z., Dao, T., Dziech, A.L., Subbian, V., and Beyette, F.R. (2013, January 3\u20137). Development of a Point-of-Care Medical Device to Measure Head Impact in Contact Sports. Osaka, Japan.","DOI":"10.1109\/EMBC.2013.6610463"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Zulkifli, N.S.A., Harun, F.K.C., and Azahar, N.S. (2012, January 27\u201328). XBee Wireless Sensor Networks for Heart Rate Monitoring in Sport Training. Penang, Malaysia.","DOI":"10.1109\/ICoBE.2012.6179054"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Gong, M., Zhang, L., Ding, Z., Dong, F., and Wang, L. (2012, January 19\u201320). Research and development of swimming training information system based on ZigBee technology. Yantai, China.","DOI":"10.1109\/ICSAI.2012.6223170"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"189","DOI":"10.2528\/PIERB12070904","article-title":"Evaluation of electromagnetic dosimetry of wireless systems in complex indoor scenarios with human body interaction","volume":"43","author":"Aguirre","year":"2012","journal-title":"Prog. Electromagn. Res. B"},{"key":"ref_22","unstructured":"Miyu, M., and Shinsuke, H. (2013, January 6\u20138). A Cooperative Relaying Scheme for Real-Time Vital Data Gathering in a Wearable Wireless Body Area Network. Tokyo, Japan."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Mazumder, O., Kundu, A.S., and Bhaumik, S. (2012, January 28\u201329). Development of wireless insole foot pressure data acquisition device. Kolkata, India.","DOI":"10.1109\/CODIS.2012.6422198"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"9884","DOI":"10.3390\/s120709884","article-title":"Foot Plantar Pressure Measurement System: A Review","volume":"12","author":"Zayegh","year":"2012","journal-title":"Sensors"},{"key":"ref_25","first-page":"256","article-title":"Convergence Analysis in Deterministic 3D Ray Launching Radio Channel Estimation in Complex Environments","volume":"29","author":"Azpilicueta","year":"2014","journal-title":"ACES J."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2777","DOI":"10.1109\/TAP.2014.2308518","article-title":"A Ray Launching-Neural Network Approach for Radio Wave Propagation Analysis in Complex Indoor Environments","volume":"62","author":"Azpilicueta","year":"2014","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"8003","DOI":"10.3390\/s140508003","article-title":"Ubiquitous Connected Train based on Train-to-Ground and Intra-Wagon Communications Capable of Providing On Trip Customized Digital Services for Passengers","volume":"14","author":"Salaberria","year":"2014","journal-title":"Sensors"},{"key":"ref_28","first-page":"412","article-title":"Analysis of Topological Impact on Wireless Channel Performance on Intelligent Street Lighting System","volume":"23","author":"Azpilicueta","year":"2014","journal-title":"Radioengineering"},{"key":"ref_29","first-page":"47","article-title":"Ontology Based Road Traffic Management","volume":"1\u20132","author":"Bermejo","year":"2014","journal-title":"Ad Hoc Sens. Wirel. Netw."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Aguirre, E., Lopez-Iturri, P., Azpilicueta, L., de Miguel-Bilbao, S., Ramos, V., G\u00e1rate, U., and Falcone, F. (2014). Analysis of Estimation of Electromagnetic Dosimetric Values from Non-Ionizing Radiofrequency Fields in Conventional Road Vehicle Environments. Electromag. Biol. Med.","DOI":"10.3109\/15368378.2013.863782"},{"key":"ref_31","first-page":"240","article-title":"Characterization and Consideration of Topological Impact of Wireless Propagation in a Commercial Aircraft Environment","volume":"5","author":"Aguirre","year":"2013","journal-title":"IEEE Antennas Propag. Mag."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"2126","DOI":"10.1002\/mop.27010","article-title":"Measurement and modeling of a UHF-RFID system in a metallic closed vehicle","volume":"54","author":"Azpilicueta","year":"2012","journal-title":"Microw. Opt. Technol. Lett."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1109\/8.18707","article-title":"A Heuristic UTD Slope Diffraction Coefficient for Rough Lossy Wedges","volume":"37","author":"Luebbers","year":"1989","journal-title":"IEEE Trans. Antennas Propag."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/12\/24004\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:10:55Z","timestamp":1760217055000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/12\/24004"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,12,12]]},"references-count":33,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2014,12]]}},"alternative-id":["s141224004"],"URL":"https:\/\/doi.org\/10.3390\/s141224004","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2014,12,12]]}}}