{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:28:34Z","timestamp":1760059714608,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,3]],"date-time":"2025-07-03T00:00:00Z","timestamp":1751500800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Humanities and Social Science Fund of Ministry of Education","award":["23YJAZH122","62104208"],"award-info":[{"award-number":["23YJAZH122","62104208"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["23YJAZH122","62104208"],"award-info":[{"award-number":["23YJAZH122","62104208"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>With the rapid development of smart connected vehicles, vehicle network communications demand high-speed data transmission to support advanced automotive services. Millimeter Wave (mmWave) communication offers fast data rates, strong anti-interference capabilities, high precision localization and low-latency, making it suitable for high-speed in-vehicle communications. However, mmWave communication performance in vehicular networks is hindered by high path loss and frequent beam alignment updates, significantly degrading the coverage and connectivity of vehicle nodes (VNs). In addition, atmospheric propagation attenuation further deteriorates signal quality and limits system performance due to raindrop absorption and scattering. Therefore, the pure mmWave networks cannot meet the high requirements of highway vehicular communications. To address these challenges, this paper proposes a hybrid mmWave and microwave network architecture to improve VNs\u2019 coverage and connectivity performances through the strategic deployment of Roadside Units (RSUs). Using Radio Access Technology (RAT), mmWave and microwave RSUs are symmetrically deployed on both sides of the road to communicate with VNs located at the road center. This symmetric RSUs deployment significantly improves the network reliability. Analytical expressions for coverage and connectivity in the proposed hybrid networks are derived and compared with the pure mmWave networks, accounting for rainfall attenuation. The study results show that the proposed hybrid network shows better performance than the pure mmWave network in both coverage and connectivity.<\/jats:p>","DOI":"10.3390\/sym17071054","type":"journal-article","created":{"date-parts":[[2025,7,3]],"date-time":"2025-07-03T08:22:07Z","timestamp":1751530927000},"page":"1054","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Strategy for Improving Millimeter Wave Communication Reliability by Hybrid Network Considering Rainfall Attenuation"],"prefix":"10.3390","volume":"17","author":[{"given":"Jiaqing","family":"Sun","sequence":"first","affiliation":[{"name":"College of Information Engineering, Yangzhou University, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7830-2848","authenticated-orcid":false,"given":"Chunxiao","family":"Li","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Yangzhou University, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Junfeng","family":"Wei","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Yangzhou University, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiajun","family":"Shen","sequence":"additional","affiliation":[{"name":"College of Civil Science and Engineering, Yangzhou University, Yangzhou 225009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"829","DOI":"10.1109\/JIOT.2018.2812300","article-title":"A Survey of the State-of-the-Art Localization Techniques and Their Potentials for Autonomous Vehicle Applications","volume":"5","author":"Kuutti","year":"2018","journal-title":"IEEE Internet Things J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"760","DOI":"10.1109\/TITS.2018.2818888","article-title":"A Survey on Recent Advances in Vehicular Network Security, Trust, and Privacy","volume":"20","author":"Lu","year":"2019","journal-title":"IEEE Trans. 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