{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:04:58Z","timestamp":1760058298223,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,3,28]],"date-time":"2025-03-28T00:00:00Z","timestamp":1743120000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\/MCTES","award":["UIDB\/EEA\/50008\/2020","2022.03897.PTDC."],"award-info":[{"award-number":["UIDB\/EEA\/50008\/2020","2022.03897.PTDC."]}]},{"name":"EU","award":["UIDB\/EEA\/50008\/2020","2022.03897.PTDC."],"award-info":[{"award-number":["UIDB\/EEA\/50008\/2020","2022.03897.PTDC."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>In Large Intelligent Surface (LIS) systems, achieving accurate channel estimation is essential for enhancing communication quality and system efficiency. The main focus of this study is on using the Least Squares (LS) method to estimate pilot-based channels. It also looks at more advanced methods, like using low-density parity-check (LDPC) codes, antenna selection, and optimized pilot design, to make the method more accurate and effective. We employ orthogonal pilot sequences to reduce signal interference and improve pilot power to enhance estimation performance. Additionally, LDPC codes play a crucial role in eliminating noise and interference effects, thereby improving system reliability. We also propose selective configurations of LIS antennas to balance high performance with reduced computational costs. Collectively, these strategies lead to a significant reduction in the Bit Error Rate (BER) and a remarkable improvement in the overall system performance, offering a practical solution for complex LIS deployments.<\/jats:p>","DOI":"10.3390\/app15073743","type":"journal-article","created":{"date-parts":[[2025,3,31]],"date-time":"2025-03-31T05:10:07Z","timestamp":1743397807000},"page":"3743","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Improved Low-Complexity, Pilot-Based Channel Estimation for Large Intelligent Surface Systems"],"prefix":"10.3390","volume":"15","author":[{"given":"Ali","family":"Gashtasbi","sequence":"first","affiliation":[{"name":"Faculty of Sciences and Technology, Universidade Nova, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5498-3220","authenticated-orcid":false,"given":"M\u00e1rio","family":"Marques da Silva","sequence":"additional","affiliation":[{"name":"Department of Sciences and Technologies, Universidade Aut\u00f3noma de Lisboa, 1169-023 Lisboa, Portugal"},{"name":"Autonoma TechLab, 1169-023 Lisboa, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 1049-001 Lisboa, Portugal"},{"name":"Ci2\u2014Centro de Investiga\u00e7\u00e3o em Cidades Inteligentes, 2300-313 Tomar, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8520-7267","authenticated-orcid":false,"given":"Rui","family":"Dinis","sequence":"additional","affiliation":[{"name":"Faculty of Sciences and Technology, Universidade Nova, 2829-516 Caparica, Portugal"},{"name":"Autonoma TechLab, 1169-023 Lisboa, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"40","DOI":"10.23919\/JCIN.2019.8917871","article-title":"Large Intelligent Surface\/Antennas (LISA): Making Reflective Radios Smart","volume":"4","author":"Liang","year":"2019","journal-title":"J. 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