{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T18:58:53Z","timestamp":1771700333366,"version":"3.50.1"},"reference-count":42,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,6,9]],"date-time":"2023-06-09T00:00:00Z","timestamp":1686268800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Jiangsu University Student Innovation Training Program","award":["2022111117070Z"],"award-info":[{"award-number":["2022111117070Z"]}]},{"name":"Jiangsu University Student Innovation Training Program","award":["61401387"],"award-info":[{"award-number":["61401387"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2022111117070Z"],"award-info":[{"award-number":["2022111117070Z"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61401387"],"award-info":[{"award-number":["61401387"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Vehicular ad hoc network (VANET) communications face severe fading problems due to the signal reflections and diffractions within tunnels. Unlike the open road, the space of a tunnel is very limited, so VANET communication performance in a tunnel is seriously affected. In the process of signal transmission, the reflected signal is symmetrical with the incident signal after it is reflected by the road and the wall. In this paper, we establish a mathematical model of path loss for V2V (Vehicle-to-Vehicle) communication based on the principle of signal reflection symmetry in tunnels and considering several factors, such as the tunnel surface and the color of the tunnel wall. In addition, we use cooperative communication to form a virtual multiple-input multiple-output (V-MIMO) system, to improve the communication quality in tunnels. In the proposed system, the OBU (On-Board-unit) and RSU (Road-Side-Unit) share each other\u2019s antennas, so that wireless cooperative communication can be employed, without increasing the number of antennas in a one-way tunnel. Therefore, this multipath fading internal electromagnetic wave propagation model can be used to improve performance. A deep reinforcement learning algorithm was used to solve the pairing problem to obtain a more accurate OBU and RSU pair, to form a V-MIMO system. Here, the RSU is regarded as an agent and interacts with the OBU in the tunnel. The optimal strategy was learned in a real-time changing simulation environment, and the experiment verified the convergence of the algorithm. The simulation results showed that, compared with the Q-learning based scheme, the optimal matching algorithm based on V-MIMO and a DQN (Deep Q-network) could effectively reduce the probability of transmission outages and improve the communication efficiency in tunnels.<\/jats:p>","DOI":"10.3390\/sym15061230","type":"journal-article","created":{"date-parts":[[2023,6,9]],"date-time":"2023-06-09T08:37:33Z","timestamp":1686299853000},"page":"1230","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Path Loss and Auxiliary Communication Analysis of VANET in Tunnel Environments"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7830-2848","authenticated-orcid":false,"given":"Chunxiao","family":"Li","sequence":"first","affiliation":[{"name":"School of Information Engineering, Yangzhou University, Yangzhou 225000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Honghui","family":"Jin","sequence":"additional","affiliation":[{"name":"School of Information Engineering, Yangzhou University, Yangzhou 225000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wen","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Information Engineering, Yangzhou University, Yangzhou 225000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mei","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Information Engineering, Yangzhou University, Yangzhou 225000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qingyue","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Information Engineering, Yangzhou University, Yangzhou 225000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuanpeng","family":"Pei","sequence":"additional","affiliation":[{"name":"School of Information Engineering, Yangzhou University, Yangzhou 225000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1109\/MVT.2017.2777259","article-title":"Connected Roads of the Future: Use Cases, Requirements, and Design Considerations for Vehicle-to-Everything Communications","volume":"13","author":"Boban","year":"2018","journal-title":"IEEE Veh. Technol. Mag."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Ferreira, M., Damas, L., Conceic\u00e3o, H., d\u2019Orey, P.M., Fernandes, R., Steenkiste, P., and Gomes, P. (2014, January 8\u201311). Self-automated parking lots for autonomous vehicles based on vehicular ad hoc networking. Proceedings of the 2014 IEEE Intelligent Vehicles Symposium, Dearborn, MI, USA.","DOI":"10.1109\/IVS.2014.6856561"},{"key":"ref_3","unstructured":"3GPP (2015). Study on LTE Support for V2X Services (Release 14), 3rd Generation Partnership Project. Tech. Rep. 3GPP TR 22.885 V1.0.0."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1109\/MCOMSTD.2019.1800049","article-title":"Supporting Enhanced Vehicle-to-Everything Services by LTE Release 15 Systems","volume":"3","author":"Fodor","year":"2019","journal-title":"IEEE Commun. Stand. Mag."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1109\/MITS.2010.938166","article-title":"Emergency Services in Future Intelligent Transportation Systems Based on Vehicular Communication Networks","volume":"2","author":"Martinez","year":"2010","journal-title":"IEEE Intell. Transp. Syst. Mag."},{"key":"ref_6","unstructured":"3GPP (2016). Study Enhancement of 3GPP Support for 5G V2X Services (Release 15), 3rd Generation Partnership Project. Tech. Rep. 3GPP TR 22.886 V1.0.0."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1109\/MCOMSTD.2017.1700015","article-title":"Vehicle-to-Everything (v2x) Services Supported by LTE-Based Systems and 5G","volume":"1","author":"Chen","year":"2017","journal-title":"IEEE Commun. Stand. Mag."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"e09336","DOI":"10.1016\/j.heliyon.2022.e09336","article-title":"High Gain Modified Vivaldi Vehicular Antenna for IoV Communications in 5G Network","volume":"8","author":"Kapoor","year":"2022","journal-title":"Heliyon"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"931","DOI":"10.1109\/LAWP.2014.2322261","article-title":"Path Loss Characterization for Vehicular Communications at 700 MHz and 5.9 GHz Under LOS and NLOS Conditions","volume":"13","author":"Rubio","year":"2014","journal-title":"IEEE Antennas Wirel. Propag. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"658","DOI":"10.1109\/SURV.2013.091213.00175","article-title":"A Survey of Radio Propagation Modeling for Tunnels","volume":"16","author":"Hrovat","year":"2014","journal-title":"IEEE Commun. Surv. Tutorials"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Klozar, L., and Prokopec, J. (2011, January 19\u201320). Propagation path loss models for mobile communication. Proceedings of the 21st International Conference Radioelektronika, Brno, Czech Republic.","DOI":"10.1109\/RADIOELEK.2011.5936478"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Tian, J., and Meng, F. (2020, January 20\u201322). Comparison Survey of Mobility Models in Vehicular Ad-Hoc Network (VANET). Proceedings of the 2020 IEEE 3rd International Conference on Automation, Electronics and Electrical Engineering (AUTEEE), Shenyang, China.","DOI":"10.1109\/AUTEEE50969.2020.9315583"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Li, H., Zhou, Y., Shen, B., Ling, L., Xia, J., Yang, T., Lu, Q., Zhou, Y., and Liu, Y. (2020, January 12\u201314). Research on Tunnel Wireless Communication Technology. Proceedings of the 2020 International Conference on Wireless Communications and Smart Grid (ICWCSG), Qingdao, China.","DOI":"10.1109\/ICWCSG50807.2020.00024"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Shakhobiddinov, A., Shamsiev, A., Narzullaev, I., and Shoniyozov, G. (2019, January 4\u20136). About Organization of Mobile Communications in Long Car Tunnels. Proceedings of the 2019 International Conference on Information Science and Communications Technologies (ICISCT), Tashkent, Uzbekistan.","DOI":"10.1109\/ICISCT47635.2019.9011958"},{"key":"ref_15","unstructured":"Rashdi, M.A., Nadir, Z., and Al-Lawati, H. (2020, January 9\u201312). Applicability of Okumura\u2013Hata Model for Wireless Communication Systems in Oman. Proceedings of the 2020 IEEE International IOT, Electronics and Mechatronics Conference (IEMTRONICS), Vancouver, BC, Canada."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Akhpashev, R.V., and Andreev, A.V. (July, January 30). COST 231 Hata adaptation model for urban conditions in LTE networks. Proceedings of the 2016 17th International Conference of Young Specialists on Micro\/Nanotechnologies and Electron Devices (EDM), Erlagol, Russia.","DOI":"10.1109\/EDM.2016.7538693"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Galvan-Tejada, G.M. (2010, January 8\u201310). WiMAX urban coverage based on the Lee model and the Deygout diffraction method. Proceedings of the 2010 7th International Conference on Electrical Engineering Computing Science and Automatic Control, Tuxtla Gutierrez, Mexico.","DOI":"10.1109\/ICEEE.2010.5608571"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Wang, W., Zhang, Y., Yao, W., and Wang, S. (2009, January 16\u201318). The propagation model of RFID systems in ETC. Proceedings of the 2009 IEEE International Conference on Communications Technology and Applications, Beijing, China.","DOI":"10.1109\/ICCOMTA.2009.5349238"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Onipe, J.A., Alenoghena, C.O., Salawu, N., and Numan, P.E. (2020, January 18\u201321). Optimal Propagation Models for Path-loss Prediction in a Mountainous Environment at 2100MHz. Proceedings of the 2020 International Conference in Mathematics, Computer Engineering and Computer Science (ICMCECS), Ayobo, Nigeria.","DOI":"10.1109\/ICMCECS47690.2020.246994"},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Prior, P., and Cota, N. (2021, January 1\u20133). Railways Communications Propagation Prediction over Irregular Terrain using Longley-Rice Model. Proceedings of the 2021 28th International Conference on Telecommunications (ICT), London, UK.","DOI":"10.1109\/ICT52184.2021.9511515"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Abdulrasheed, I.Y., Faruk, N., Surajudeen-Bakinde, N.T., Olawoyin, L.A., Oloyede, A.A., and Popoola, S.I. (2017, January 7\u201310). Kriging based model for path loss prediction in the VHF band. Proceedings of the 2017 IEEE 3rd International Conference on Electro-Technology for National Development (NIGERCON), Owerri, Nigeria.","DOI":"10.1109\/NIGERCON.2017.8281892"},{"key":"ref_22","first-page":"88","article-title":"\u201cSoft Ribs\u201d of Tunnel Asphalt Pavement","volume":"22","author":"Zhi","year":"2006","journal-title":"China Highw."},{"key":"ref_23","first-page":"337","article-title":"The characteristic and damage of fire accidents in road tunnel","volume":"30","author":"Wang","year":"2011","journal-title":"Fire Sci. Technol."},{"key":"ref_24","first-page":"156","article-title":"On features and hazards of fire accidents in road tunnels","volume":"39","author":"Zhou","year":"2013","journal-title":"Shanxi Archit."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1753","DOI":"10.4028\/www.scientific.net\/KEM.336-338.1753","article-title":"Design and Properties of Fire-Proof Coating for Tunnels","volume":"40","author":"Yao","year":"2007","journal-title":"Key Eng. Mater."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1343","DOI":"10.1109\/JPROC.2011.2148150","article-title":"Near-Capacity Wireless Transceivers and Cooperative Communications in the MIMO Era: Evolution of Standards, Waveform Design, and Future Perspectives","volume":"99","author":"Hanzo","year":"2011","journal-title":"Proc. IEEE"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1451","DOI":"10.1109\/49.730453","article-title":"A simple transmit diversity technique for wireless communications","volume":"16","author":"Alamouti","year":"1998","journal-title":"IEEE J. Sel. Areas Commun."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"2272","DOI":"10.1109\/TVT.2013.2291435","article-title":"Energy-Efficiency Analysis and Optimization for Virtual-MIMO Systems","volume":"63","author":"Jiang","year":"2014","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Watanabe, I., Nishimori, K., Taniguchi, R., and Murakami, T. (2021, January 25\u201328). Effectiveness of the virtual massive MIMO in 5G with OFDM. Proceedings of the International Symposium on Antennas and Propagation (ISAP), Osaka, Japan.","DOI":"10.23919\/ISAP47053.2021.9391419"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Gong, Y., and Wang, X. (2009, January 24\u201326). Channel Capacity Analysis and Simulations of Distributed MIMO System. Proceedings of the 2009 5th International Conference on Wireless Communications, Networking and Mobile Computing, Beijing, China.","DOI":"10.1109\/WICOM.2009.5302898"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Khurana, M., and Krishna, C.R. (2015, January 4\u20135). MIMO-based spatial diversity scheme in VANET scenario. Proceedings of the 2015 1st International Conference on Next Generation Computing Technologies (NGCT), Dehradun, India.","DOI":"10.1109\/NGCT.2015.7375122"},{"key":"ref_32","unstructured":"Foerster, J., Nardelli, N., Farquhar, G., Afouras, T., Torr, P.H.S., Kohli, P., and Whiteson, S. (2017, January 6\u201311). Stabilising experience replay for deep multi-agent reinforcement learning. Proceedings of the 34th International Conference on Machine Learning, Sydney, Australia."},{"key":"ref_33","unstructured":"Mnih, V., Kavukcuoglu, K., Silver, D., Graves, A., Antonoglou, I., Wierstra, D., and Riedmiller, M. (2013). Playing Atari with Deep Reinforcement Learning. arXiv."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1038\/nature14236","article-title":"Human-level control through deep reinforcement learning","volume":"518","author":"Mnih","year":"2015","journal-title":"Nature"},{"key":"ref_35","first-page":"301","article-title":"A Path Loss Calculation Scheme for Highway ETC Charging Signal Propagation","volume":"10","author":"Li","year":"2014","journal-title":"Wseas Trans. Signal Process."},{"key":"ref_36","unstructured":"(2012). Propagation Data and Prediction Methods for the Planning of Indoor Radio Communication Systems and Radio Local Area Networks in the Frequency Range 900 MHz to 100 GHz (Standard No. ITU-R P.1238-7)."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"3949","DOI":"10.1109\/TWC.2016.2531652","article-title":"Unmanned Aerial Vehicle With Underlaid Device-to-Device Communications: Performance and Tradeoffs","volume":"15","author":"Mozaffari","year":"2016","journal-title":"IEEE Trans. Wirel. Commun."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"He, Z., Zhang, B., Wang, J., Wang, L., Ren, Y., and Han, Z. (2020, January 7\u201311). Performance Analysis and Optimization for V2V-assisted UAV Communications in Vehicular Networks. Proceedings of the IEEE International Conference on Communications (ICC), Dublin, Ireland.","DOI":"10.1109\/ICC40277.2020.9149341"},{"key":"ref_39","first-page":"276","article-title":"Correlated Channel Capacity of Virtual MIMO Based on Distributed Satellites","volume":"42","author":"Yang","year":"2015","journal-title":"Comput. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1179","DOI":"10.1109\/JAS.2019.1911732","article-title":"Path planning for intelligent robots based on deep Q-learning with experience replay and heuristic knowledge","volume":"7","author":"Jiang","year":"2020","journal-title":"IEEE\/CAA J. Autom. Sin."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"3163","DOI":"10.1109\/TVT.2019.2897134","article-title":"Deep Reinforcement Learning Based Resource Allocation for V2V Communications","volume":"68","author":"Ye","year":"2019","journal-title":"IEEE Trans. Veh. Technol."},{"key":"ref_42","first-page":"363","article-title":"Study on Reflection Coefficient of Tunnel Ceiling Materials to the Road Average Luminance","volume":"39","author":"Xiao","year":"2015","journal-title":"J. Wuhan Univ. Technol. (Transp. Sci. Eng.)"}],"container-title":["Symmetry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-8994\/15\/6\/1230\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:51:29Z","timestamp":1760125889000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-8994\/15\/6\/1230"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,6,9]]},"references-count":42,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2023,6]]}},"alternative-id":["sym15061230"],"URL":"https:\/\/doi.org\/10.3390\/sym15061230","relation":{},"ISSN":["2073-8994"],"issn-type":[{"value":"2073-8994","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,6,9]]}}}