{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T20:59:52Z","timestamp":1781211592307,"version":"3.54.1"},"reference-count":48,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2023,9,27]],"date-time":"2023-09-27T00:00:00Z","timestamp":1695772800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["ED431C 2019\/26"],"award-info":[{"award-number":["ED431C 2019\/26"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["33.50.460A.752"],"award-info":[{"award-number":["33.50.460A.752"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministerio de Ciencia e Innovaci\u00f3n","award":["ED431C 2019\/26"],"award-info":[{"award-number":["ED431C 2019\/26"]}]},{"name":"Ministerio de Ciencia e Innovaci\u00f3n","award":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"]}]},{"name":"Ministerio de Ciencia e Innovaci\u00f3n","award":["33.50.460A.752"],"award-info":[{"award-number":["33.50.460A.752"]}]},{"name":"Ministerio de Universidades","award":["ED431C 2019\/26"],"award-info":[{"award-number":["ED431C 2019\/26"]}]},{"name":"Ministerio de Universidades","award":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"]}]},{"name":"Ministerio de Universidades","award":["33.50.460A.752"],"award-info":[{"award-number":["33.50.460A.752"]}]},{"name":"European Union NextGenerationEU\/PRTR with a Margarita Salas agreement from Universidade de Vigo","award":["ED431C 2019\/26"],"award-info":[{"award-number":["ED431C 2019\/26"]}]},{"name":"European Union NextGenerationEU\/PRTR with a Margarita Salas agreement from Universidade de Vigo","award":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"]}]},{"name":"European Union NextGenerationEU\/PRTR with a Margarita Salas agreement from Universidade de Vigo","award":["33.50.460A.752"],"award-info":[{"award-number":["33.50.460A.752"]}]},{"name":"Atlantic Research Center","award":["ED431C 2019\/26"],"award-info":[{"award-number":["ED431C 2019\/26"]}]},{"name":"Atlantic Research Center","award":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"],"award-info":[{"award-number":["PID2020-112545RB-C52\/AEI\/10.13039\/501100011033"]}]},{"name":"Atlantic Research Center","award":["33.50.460A.752"],"award-info":[{"award-number":["33.50.460A.752"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Radars in the W-band are being integrated into car bumpers for functionalities such as adaptive cruise control, collision avoidance, or lane-keeping. These Advanced Driving Assistance Systems (ADAS) enhance traffic security in coordination with Intelligent Transport Systems (ITS). This paper analyzes the attenuation effect that car bumpers cause on the signals passing through them. Using the free-space transmission technique inside an anechoic chamber, we measured the attenuation caused by car bumper samples with different material compositions. The results show level drops lower than 1.25 dB in all the samples analyzed. The signal attenuation triggered by the bumpers decreases with the frequency, with differences ranging from 0.55 dB to 0.86 dB when comparing the end frequencies within the radar band. Among the analyzed bumper samples, those with a thicker varnish layer or with talc in the composition seem to attenuate more. We also provide an estimation of the measurement uncertainty for the validation of the obtained results. Uncertainty analysis yields values below 0.21 dB with a 95% coverage interval in the measured frequency band. When comparing the measured value with its uncertainty, i.e., the relative uncertainty, the lower the frequency in the measured band, the more accurate the measurements seem to be.<\/jats:p>","DOI":"10.3390\/s23198113","type":"journal-article","created":{"date-parts":[[2023,9,28]],"date-time":"2023-09-28T07:50:26Z","timestamp":1695887426000},"page":"8113","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Car Bumper Effects in ADAS Sensors at Automotive Radar Frequencies"],"prefix":"10.3390","volume":"23","author":[{"given":"Isabel","family":"Exp\u00f3sito","sequence":"first","affiliation":[{"name":"atlanTTic Research Center, Signal Theory and Communications Department, Universidade de Vigo, 36310 Vigo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ingo","family":"Chin","sequence":"additional","affiliation":[{"name":"IDLab, Department of Information Technology, Ghent University-imec, 9052 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1881-681X","authenticated-orcid":false,"given":"Manuel","family":"Garc\u00eda S\u00e1nchez","sequence":"additional","affiliation":[{"name":"atlanTTic Research Center, Signal Theory and Communications Department, Universidade de Vigo, 36310 Vigo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8391-1947","authenticated-orcid":false,"given":"I\u00f1igo","family":"Cui\u00f1as","sequence":"additional","affiliation":[{"name":"atlanTTic Research Center, Signal Theory and Communications Department, Universidade de Vigo, 36310 Vigo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4003-0098","authenticated-orcid":false,"given":"Jo","family":"Verhaevert","sequence":"additional","affiliation":[{"name":"IDLab, Department of Information Technology, Ghent University-imec, 9052 Ghent, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3201","DOI":"10.1109\/TVT.2019.2895297","article-title":"Autonomous Vehicles: Autodriver Algorithm and Vehicle Dynamics","volume":"68","author":"Marzbani","year":"2019","journal-title":"IEEE Trans. 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