{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:35:15Z","timestamp":1760240115390,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2019,3,20]],"date-time":"2019-03-20T00:00:00Z","timestamp":1553040000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"European Commission","doi-asserted-by":"publisher","award":["0246-LIMUS-4-E"],"award-info":[{"award-number":["0246-LIMUS-4-E"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Spanish Ministry of Economy and Competitiveness","award":["TIN2015-71564-C4-4-R"],"award-info":[{"award-number":["TIN2015-71564-C4-4-R"]}]},{"DOI":"10.13039\/501100014181","name":"Regional Government of Extremadura","doi-asserted-by":"publisher","award":["GR18038"],"award-info":[{"award-number":["GR18038"]}],"id":[{"id":"10.13039\/501100014181","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Self-calibrated Acoustic Local Positioning Systems (ALPS) generally require a high consumption of hardware and software resources to obtain the user\u2019s position at an acceptable update rate. To address this limitation, this work proposes a self-calibrated ALPS based on a software\/hardware co-design approach. This working architecture allows for efficient communications, signal processing tasks, and the running of the positioning algorithm on low-cost devices. This fact also enables the real-time system operation. The proposed system is composed of a minimum of four RF-synchronized active acoustic beacons, which emit spread-spectrum modulated signals to position an unlimited number of receiver nodes. Each receiver node estimates the beacons\u2019 position by means of an auto-calibration process and then computes its own position by means of a 3D multilateration algorithm. A set of experimental tests has been carried out where the feasibility of the proposed system is demonstrated. In these experiments, accuracies below 0.1 m are obtained in the determination of the receptor node position with respect to the set of previously-calibrated beacons.<\/jats:p>","DOI":"10.3390\/s19061385","type":"journal-article","created":{"date-parts":[[2019,3,21]],"date-time":"2019-03-21T04:11:56Z","timestamp":1553141516000},"page":"1385","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Easily-Deployable Acoustic Local Positioning System Based on Auto-Calibrated Wireless Beacons"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9213-7642","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Moreno","sequence":"first","affiliation":[{"name":"Sensory System Research Group, University of Extremadura, 06006 Badajoz, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7610-1452","authenticated-orcid":false,"given":"Fernando J.","family":"\u00c1lvarez","sequence":"additional","affiliation":[{"name":"Sensory System Research Group, University of Extremadura, 06006 Badajoz, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9436-5999","authenticated-orcid":false,"given":"Teodoro","family":"Aguilera","sequence":"additional","affiliation":[{"name":"Sensory System Research Group, University of Extremadura, 06006 Badajoz, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0412-0179","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Paredes","sequence":"additional","affiliation":[{"name":"Sensory System Research Group, University of Extremadura, 06006 Badajoz, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,20]]},"reference":[{"key":"ref_1","unstructured":"Misra, P., and Enge, P. 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