{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:56:20Z","timestamp":1760230580492,"version":"build-2065373602"},"reference-count":13,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,27]],"date-time":"2022-07-27T00:00:00Z","timestamp":1658880000000},"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>The 6G wireless systems are expected to have higher capacity, reliability, and energy efficiency than the existing cellular systems. Millimeter-wave (mmWave) frequencies offer high capacity at the cost of high attenuation and blockage losses. Reconfigurable intelligent surface (RIS) assisted mmWave networks consist of smaller antenna elements that control the propagation channel between the base station (BS) and the user by appropriately tuning the phase and the reflection of the incident electromagnetic signal. The deployment of RIS is considered to be an energy efficient solution to improve the coverage of regions with high blocking probability. However, if every BS is associated with one or more dedicated RIS, then the density of RIS increases proportionally with the density of BSs. Hence in this work, we propose RIS sharing mechanisms where multiple BSs share one RIS. We formulate resource allocation of RIS sharing in terms of time and the RIS elements as an optimization problem, and we propose heuristics to solve both. Further, we present detailed simulation results to compare time and the element based RIS sharing methods for various scenarios with the benchmark and the RIS system without sharing. The proposed time and element based RIS sharing methods improve throughput upto 53% and 25%, respectively, compared to the RIS system without sharing in specific scenarios.<\/jats:p>","DOI":"10.3390\/s22155619","type":"journal-article","created":{"date-parts":[[2022,7,28]],"date-time":"2022-07-28T03:21:16Z","timestamp":1658978476000},"page":"5619","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Resource Allocation and Sharing Methodologies When Reconfigurable Intelligent Surfaces Meet Multiple Base Stations"],"prefix":"10.3390","volume":"22","author":[{"given":"Yoghitha","family":"Ramamoorthi","sequence":"first","affiliation":[{"name":"NTT Access Network Service Systems Laboratories, Nippon Telegraph and Telephone Corporation, Yokosuka 239-0847, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Riku","family":"Ohmiya","sequence":"additional","affiliation":[{"name":"NTT Access Network Service Systems Laboratories, Nippon Telegraph and Telephone Corporation, Yokosuka 239-0847, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masashi","family":"Iwabuchi","sequence":"additional","affiliation":[{"name":"NTT Access Network Service Systems Laboratories, Nippon Telegraph and Telephone Corporation, Yokosuka 239-0847, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomoaki","family":"Ogawa","sequence":"additional","affiliation":[{"name":"NTT Access Network Service Systems Laboratories, Nippon Telegraph and Telephone Corporation, Yokosuka 239-0847, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yasushi","family":"Takatori","sequence":"additional","affiliation":[{"name":"NTT Access Network Service Systems Laboratories, Nippon Telegraph and Telephone Corporation, Yokosuka 239-0847, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,27]]},"reference":[{"unstructured":"(2022). 5G Evolution and 6G, Japan, NTT DOCOMO, Inc.. White Paper.","key":"ref_1"},{"doi-asserted-by":"crossref","unstructured":"Di, B. (2021, January 10\u201313). Sharing the Surface: RIS-aided Distributed Mechanism Design for Hybrid Beamforming in Multi-cell Multi-user Networks. Proceedings of the IEEE INFOCOM 2021\u2014IEEE Conference on Computer Communications Workshops (INFOCOM WKSHPS), Vancouver, BC, Canada.","key":"ref_2","DOI":"10.1109\/INFOCOMWKSHPS51825.2021.9484464"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"740","DOI":"10.1109\/LWC.2020.3042189","article-title":"Delay-Optimal Scheduling for IRS-Aided Mobile Edge Computing","volume":"10","author":"Zhou","year":"2021","journal-title":"IEEE Wirel. Commun. Lett."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4522","DOI":"10.1109\/TCOMM.2020.2981458","article-title":"Intelligent Reflecting Surface Meets OFDM: Protocol Design and Rate Maximization","volume":"68","author":"Yang","year":"2020","journal-title":"IEEE Trans. Commun."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"163086","DOI":"10.1109\/ACCESS.2021.3133139","article-title":"IRS-Aided Physical Layer Network Slicing for URLLC and eMBB","volume":"9","author":"Souto","year":"2021","journal-title":"IEEE Access"},{"doi-asserted-by":"crossref","unstructured":"Zhu, Y., Liu, Y., Zhao, J., Li, M., and Wu, Q. (2021, January 7\u201311). Joint Time Allocation and Beamforming Design for IRS-Aided Coexistent Cellular and Sensor Networks. Proceedings of the IEEE Global Communications Conference (GLOBECOM), Madrid, Spain.","key":"ref_6","DOI":"10.1109\/GLOBECOM46510.2021.9685970"},{"doi-asserted-by":"crossref","unstructured":"Kassem, M., Hassan, H.A.H., Nasser, A., Mansour, A., and Yao, K.-C. (2021, January 11\u201313). Users Selection and Resource Allocation in Intelligent Reflecting Surfaces Assisted Cellular Networks. Proceedings of the 17th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), Bologna, Italy.","key":"ref_7","DOI":"10.1109\/WiMob52687.2021.9606350"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1667","DOI":"10.1109\/JSAC.2022.3143216","article-title":"Mobility-aware User Association Strategy for IRS-aided mm-wave Multibeam Transmission Towards 6G","volume":"40","author":"Hashida","year":"2022","journal-title":"IEEE J. Sel. Areas Commun."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"83","DOI":"10.52953\/GSCS6789","article-title":"Massive distributed IRS aided wireless communication with ON\/OFF selection","volume":"2","author":"Ohmiya","year":"2021","journal-title":"ITU J. Future Evol. Technol."},{"doi-asserted-by":"crossref","unstructured":"Ramamoorthi, Y., Iwabuchi, M., Murakami, T., Ogawa, T., and Takatori, Y. (2022, June 25). 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Available online: https:\/\/portal.3gpp.org\/desktopmodules\/Specifications\/SpecificationDetails.aspx?specificationId=3173.","key":"ref_13"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/15\/5619\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:57:32Z","timestamp":1760140652000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/15\/5619"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,7,27]]},"references-count":13,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2022,8]]}},"alternative-id":["s22155619"],"URL":"https:\/\/doi.org\/10.3390\/s22155619","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2022,7,27]]}}}