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Traditional methods to improve signal quality, such as adding access points, often fall short in dynamic environments where user movement and physical obstructions affect signal behavior. In this work, we propose a system that leverages existing Internet of Things (IoT) devices to perform real-time user localization and network adaptation using fine-grained Channel State Information (CSI) and Received Signal Strength Indicator (RSSI) measurements. We deploy multiple ESP-32 microcontroller-based receivers in fixed positions to capture wireless signal characteristics and process them through a pipeline that includes filtering, segmentation, and feature extraction. Using supervised machine learning, we accurately predict the user\u2019s location within a defined indoor grid. Our system achieves over 82% accuracy in a realistic laboratory setting and shows improved performance when excluding redundant sensors. The results demonstrate the potential of communication-based sensing to enhance both user tracking and wireless connectivity without requiring additional infrastructure.<\/jats:p>","DOI":"10.3390\/fi17090395","type":"journal-article","created":{"date-parts":[[2025,9,2]],"date-time":"2025-09-02T08:23:38Z","timestamp":1756801418000},"page":"395","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["From CSI to Coordinates: An IoT-Driven Testbed for Individual Indoor Localization"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-2904-078X","authenticated-orcid":false,"given":"Diana","family":"Macedo","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es (IT), 3810-193 Aveiro, Portugal"},{"name":"Department of Electrical and Computer Engineering (DEEC), University of Coimbra, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-1154-2628","authenticated-orcid":false,"given":"Miguel","family":"Loureiro","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es (IT), 3810-193 Aveiro, Portugal"},{"name":"Department of Electrical and Computer Engineering (DEEC), University of Coimbra, 3030-290 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5165-6905","authenticated-orcid":false,"given":"\u00d3scar G.","family":"Martins","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es (IT), 3810-193 Aveiro, Portugal"},{"name":"CRACS\/INESCTEC, CISUC and Department of Computer Science, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6418-2312","authenticated-orcid":false,"given":"Joana Coutinho","family":"Sousa","sequence":"additional","affiliation":[{"name":"NOS Inova\u00e7\u00e3o, 1000-029 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5337-0430","authenticated-orcid":false,"given":"David","family":"Belo","sequence":"additional","affiliation":[{"name":"NOS Inova\u00e7\u00e3o, 1000-029 Lisboa, Portugal"},{"name":"Safe AI [4U], 2485-201 Mira de Aire, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1124-525X","authenticated-orcid":false,"given":"Marco","family":"Gomes","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es (IT), 3810-193 Aveiro, Portugal"},{"name":"Department of Electrical and Computer Engineering (DEEC), University of Coimbra, 3030-290 Coimbra, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Adame, T., Carrascosa, M., and Bellalta, B. 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