{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,22]],"date-time":"2025-10-22T22:28:20Z","timestamp":1761172100935,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T00:00:00Z","timestamp":1760918400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012164","name":"National High-tech Research and Development Program","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100012164","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62201012"],"award-info":[{"award-number":["62201012"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>Time and frequency standards constitute fundamental requirements for diverse applications spanning daily life technologies to advanced scientific research. Among precision time dissemination methods, microwave-clock-based dual comb time transfer has emerged as a promising approach that achieves ultra-precise time interval measurements through linear optical sampling. However, conventional peak detection methodologies employed in such systems exhibit critical limitations: vulnerability to amplitude noise interference and inherent accuracy constraints imposed by analog sampling rates. To address these challenges, we present a novel digital time differential measurement paradigm integrating three key algorithmic innovations: (1) adaptive signal detection and extraction protocols, (2) multi-stage noise suppression processing, and (3) optimized centroid determination techniques. This comprehensive digital processing framework significantly enhances both measurement stability and operational efficiency, demonstrating single-shot temporal resolution at 17.6 fs stability levels. Our method establishes new capabilities for high-precision time-frequency transfer applications requiring robust noise immunity and enhanced sampling dynamics.<\/jats:p>","DOI":"10.3390\/sym17101769","type":"journal-article","created":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T09:23:34Z","timestamp":1760952214000},"page":"1769","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["High-Precision Digital Time-Interval Measurement in Dual-Comb Systems via Adaptive Signal Processing and Centroid Localization"],"prefix":"10.3390","volume":"17","author":[{"given":"Ganbin","family":"Lu","sequence":"first","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"given":"Dongrui","family":"Yu","sequence":"additional","affiliation":[{"name":"School of Electronics, Institute of Quantum Electronics, State Key Laboratory of Photonics and Communications, and Center for Quantum Information Technology, Peking University, Beijing 100871, China"}]},{"given":"Ziyue","family":"Zhang","sequence":"additional","affiliation":[{"name":"China Academy of Aerospace System and Innovation, Beijing 100048, China"}]},{"given":"Yang","family":"Xie","sequence":"additional","affiliation":[{"name":"China Academy of Aerospace System and Innovation, Beijing 100048, China"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-8723-1683","authenticated-orcid":false,"given":"Yufei","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Electronics, Institute of Quantum Electronics, State Key Laboratory of Photonics and Communications, and Center for Quantum Information Technology, Peking University, Beijing 100871, China"}]},{"given":"Zhongyuan","family":"Fu","sequence":"additional","affiliation":[{"name":"China Academy of Aerospace System and Innovation, Beijing 100048, China"}]},{"given":"Sifei","family":"Chen","sequence":"additional","affiliation":[{"name":"China Academy of Aerospace System and Innovation, Beijing 100048, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3678-5271","authenticated-orcid":false,"given":"Lin","family":"Xiao","sequence":"additional","affiliation":[{"name":"China Academy of Aerospace System and Innovation, Beijing 100048, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8343-8029","authenticated-orcid":false,"given":"Ziyang","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electronics, Institute of Quantum Electronics, State Key Laboratory of Photonics and Communications, and Center for Quantum Information Technology, Peking University, Beijing 100871, China"}]},{"given":"Bin","family":"Luo","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0644-6698","authenticated-orcid":false,"given":"Hong","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Electronics, Institute of Quantum Electronics, State Key Laboratory of Photonics and Communications, and Center for Quantum Information Technology, Peking University, Beijing 100871, China"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"nwaf236","DOI":"10.1093\/nsr\/nwaf236","article-title":"Time-Frequency Transfer over Optical Fiber","volume":"12","author":"Chen","year":"2025","journal-title":"Natl. 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