{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,17]],"date-time":"2026-05-17T08:09:31Z","timestamp":1779005371841,"version":"3.51.4"},"reference-count":32,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T00:00:00Z","timestamp":1769990400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2014NextGenerationEU\u2013Project Title, \u201cTime Sensitive Networking for future enabling technologies: measurement methods and metrological characterization in hybrid wired\/wireless scenarios,\u201d","award":["D53D23016070001"],"award-info":[{"award-number":["D53D23016070001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>This paper examines precise timestamping of LoRaWAN messages (particularly beacons) to enable wide-area synchronization for end devices without GNSS. The need for accuracy demands hardware-level timestamping architectures, possibly using time-domain cross-correlation (matched filtering) against internally generated chirp references. Focusing on Time-of-Arrival (TOA) estimation from raw IQ samples, the authors analyze effects of non-idealities\u2014additive white Gaussian noise (AWGN), Carrier Frequency Offset (CFO), Sampling Phase and Frequency Offset (SPO and SFO, respectively), and radio parameters such as spreading factor (SF) and sampling rate of the baseband signals. A MATLAB (R2020) simulation mimics preamble detection and Start-of-Frame Delimiter (SFD) timestamping while sweeping SF (7, 9, 12), sampling rates (0.25\u201310 MSa\/s), SNR (\u221220 to +20 dB), and CFO\/SFO offsets (\u221210\u201310 ppm frequency deviation). Errors are evaluated in terms of mean and dispersion, the latter represented by the P95\u2013P5 range metric. Results show that oversampling not only improves temporal resolution, but sub-microsecond error dispersion can be achieved with high sampling rates in favorable SNR and SF cases. Indeed, SPO and SNR greatly contribute to error dispersion. On the other hand, higher SF values increase correlation robustness at the cost of longer chirps, making SFO a dominant error source; \u00b110 ppm SFO can induce roughly \u00b13 \u03bcs SFD bias for SF12. CFO largely cancels after up-\/down-chirp averaging. As a concluding remark, matched-filter hardware timestamping can ensure sub-\u03bcs errors thanks to oversampling but requires SFO compensation for accurate real-world synchronization in practice.<\/jats:p>","DOI":"10.3390\/fi18020080","type":"journal-article","created":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T10:48:01Z","timestamp":1770115681000},"page":"80","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["LoRa\/LoRaWAN Time Synchronization: A Comprehensive Analysis, Performance Evaluation, and Compensation of Frame Timestamping"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7300-1053","authenticated-orcid":false,"given":"Stefano","family":"Rinaldi","sequence":"first","affiliation":[{"name":"Department of Information Engineering, University of Brescia, via Branze 38, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elia","family":"Mondini","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Brescia, via Branze 38, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6349-4410","authenticated-orcid":false,"given":"Paolo","family":"Ferrari","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Brescia, via Branze 38, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2046-0720","authenticated-orcid":false,"given":"Alessandra","family":"Flammini","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Brescia, via Branze 38, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5012-443X","authenticated-orcid":false,"given":"Emiliano","family":"Sisinni","sequence":"additional","affiliation":[{"name":"Department of Information Engineering, University of Brescia, via Branze 38, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1145\/844128.844143","article-title":"Fine-grained network time synchronization using reference broadcasts","volume":"36","author":"Elson","year":"2002","journal-title":"SIGOPS Oper. 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