{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,11]],"date-time":"2026-04-11T04:10:00Z","timestamp":1775880600237,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,4,30]],"date-time":"2025-04-30T00:00:00Z","timestamp":1745971200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, within the Research Unit CTS\u2014Center of Technology and Systems","award":["UIDB\/00066\/2023"],"award-info":[{"award-number":["UIDB\/00066\/2023"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, within the Research Unit CTS\u2014Center of Technology and Systems","award":["IPL\/2024\/INUTRAM_ISEL"],"award-info":[{"award-number":["IPL\/2024\/INUTRAM_ISEL"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Airports are complex environments where efficient localization and intelligent traffic management are essential for ensuring smooth navigation and operational efficiency for both pedestrians and Autonomous Guided Vehicles (AGVs). This study presents an Artificial Intelligence (AI)-driven airport traffic management system that integrates Visible Light Communication (VLC), rerouting techniques, and adaptive reward mechanisms to optimize traffic flow, reduce congestion, and enhance safety. VLC-enabled luminaires serve as transmission points for location-specific guidance, forming a hybrid mesh network based on tetrachromatic LEDs with On-Off Keying (OOK) modulation and SiC optical receivers. AI agents, driven by Deep Reinforcement Learning (DRL), continuously analyze traffic conditions, apply adaptive rewards to improve decision-making, and dynamically reroute agents to balance traffic loads and avoid bottlenecks. Traffic states are encoded and processed through Q-learning algorithms, enabling intelligent phase activation and responsive control strategies. Simulation results confirm that the proposed system enables more balanced green time allocation, with reductions of up to 43% in vehicle-prioritized phases (e.g., Phase 1 at C1) to accommodate pedestrian flows. These adjustments lead to improved route planning, reduced halting times, and enhanced coordination between AGVs and pedestrian traffic across multiple intersections. Additionally, traffic flow responsiveness is preserved, with critical clearance phases maintaining stability or showing slight increases despite pedestrian prioritization. Simulation results confirm improved route planning, reduced halting times, and enhanced coordination between AGVs and pedestrian flows. The system also enables accurate indoor localization without relying on a Global Positioning System (GPS), supporting seamless movement and operational optimization. By combining VLC, adaptive AI models, and rerouting strategies, the proposed approach contributes to safer, more efficient, and human-centered airport mobility.<\/jats:p>","DOI":"10.3390\/s25092842","type":"journal-article","created":{"date-parts":[[2025,5,1]],"date-time":"2025-05-01T09:16:12Z","timestamp":1746090972000},"page":"2842","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Enhancing Airport Traffic Flow: Intelligent System Based on VLC, Rerouting Techniques, and Adaptive Reward Learning"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1150-9895","authenticated-orcid":false,"given":"Manuela","family":"Vieira","sequence":"first","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"UNINOVA-CTS and LASI, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"},{"name":"DEE NOVA School of Science and Technology, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"given":"Manuel Augusto","family":"Vieira","sequence":"additional","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"UNINOVA-CTS and LASI, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-4267-0389","authenticated-orcid":false,"given":"Gon\u00e7alo","family":"Galv\u00e3o","sequence":"additional","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"DEE NOVA School of Science and Technology, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"given":"Paula","family":"Louro","sequence":"additional","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"UNINOVA-CTS and LASI, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-0351","authenticated-orcid":false,"given":"Alessandro","family":"Fantoni","sequence":"additional","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"UNINOVA-CTS and LASI, Quinta da Torre, Monte da Caparica, 2829-516 Caparica, Portugal"}]},{"given":"Pedro","family":"Vieira","sequence":"additional","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, Instituto Superior T\u00e9cnico, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8556-4507","authenticated-orcid":false,"given":"M\u00e1rio","family":"V\u00e9stias","sequence":"additional","affiliation":[{"name":"Electronics Telecommunication and Computer Department, Instituto Superior de Engenharia de Lisboa-Instituto Polit\u00e9cnico de Lisboa, 1949-014 Lisboa, Portugal"},{"name":"INESC-INOV, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1000-029 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1109\/MCOM.2015.7060497","article-title":"WiFi-based indoor positioning","volume":"53","author":"Yang","year":"2015","journal-title":"IEEE Commun. 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