{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T00:04:14Z","timestamp":1770681854907,"version":"3.49.0"},"reference-count":29,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2024,11,2]],"date-time":"2024-11-02T00:00:00Z","timestamp":1730505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["2023YFC2205400"],"award-info":[{"award-number":["2023YFC2205400"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["U20A0193"],"award-info":[{"award-number":["U20A0193"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key R&amp;D Program of China","doi-asserted-by":"publisher","award":["2021RC3073"],"award-info":[{"award-number":["2021RC3073"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2023YFC2205400"],"award-info":[{"award-number":["2023YFC2205400"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U20A0193"],"award-info":[{"award-number":["U20A0193"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["2021RC3073"],"award-info":[{"award-number":["2021RC3073"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Innovation Program of Hunan Province","award":["2023YFC2205400"],"award-info":[{"award-number":["2023YFC2205400"]}]},{"name":"Science and Technology Innovation Program of Hunan Province","award":["U20A0193"],"award-info":[{"award-number":["U20A0193"]}]},{"name":"Science and Technology Innovation Program of Hunan Province","award":["2021RC3073"],"award-info":[{"award-number":["2021RC3073"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The time of a satellite navigation system is primarily generated by the main control station of the ground system. Consequently, when ground stations fail, there is a risk to the continuous provision of time services to the equipment and users. Furthermore, the anticipated launch of additional satellites will further strain the satellite\u2013ground link. Next-generation satellite navigation systems will rely on time deviation measurements from inter-satellite links to independently establish and maintain a space-based time reference, enhancing the system\u2019s reliability and robustness. The increasing number of low-Earth-orbit satellite navigation constellations provides ample resources for establishing a space-based time reference. However, this also introduces challenges, including extensive time scale computations, increased link noise, and low clock resource utilization. To address these issues, this paper proposes a Distributed Kalman Plus Weight (D-KPW) algorithm, which combines the benefits of Kalman filtering and the weighted average algorithm, balancing the performance with computational resources. Furthermore, an adaptive clock control algorithm, D-KPW (Control), is developed to account for both the short-term and long-term frequency stability of the time reference. The experimental results demonstrate that the frequency stability of the time reference established by the D-KPW (Control) algorithm reaches 7.40\u00d710\u221215 and 2.30\u00d710\u221215 for sampling intervals of 1000 s and 1,000,000 s, respectively, outperforming traditional algorithms such as ALGOS. The 20-day prediction error of the time reference is 1.55 ns. Compared to traditional algorithms such as AT1, ALGOS, Kalman, and D-KPW, the accuracy improves by 65%, 65%, 66%, and 67%, respectively.<\/jats:p>","DOI":"10.3390\/rs16214092","type":"journal-article","created":{"date-parts":[[2024,11,4]],"date-time":"2024-11-04T09:52:54Z","timestamp":1730713974000},"page":"4092","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Research on Distributed Autonomous Timekeeping Algorithm for Low-Earth-Orbit Constellation"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-7258-1586","authenticated-orcid":false,"given":"Shui","family":"Yu","sequence":"first","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha 410073, China"},{"name":"Key Laboratory of Satellite Navigation Technology, Changsha 410073, China"}]},{"given":"Jing","family":"Peng","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha 410073, China"},{"name":"Key Laboratory of Satellite Navigation Technology, Changsha 410073, China"}]},{"given":"Ming","family":"Ma","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha 410073, China"},{"name":"Key Laboratory of Satellite Navigation Technology, Changsha 410073, China"}]},{"given":"Hang","family":"Gong","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha 410073, China"},{"name":"Key Laboratory of Satellite Navigation Technology, Changsha 410073, China"}]},{"given":"Zongnan","family":"Li","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha 410073, China"},{"name":"Key Laboratory of Satellite Navigation Technology, Changsha 410073, China"}]},{"given":"Shaojie","family":"Ni","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology (NUDT), Changsha 410073, China"},{"name":"Key Laboratory of Satellite Navigation Technology, Changsha 410073, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1186\/s43020-020-00012-0","article-title":"Precise Time Scales and Navigation Systems: Mutual Benefits of Timekeeping and Positioning","volume":"1","author":"Tavella","year":"2020","journal-title":"Satell. 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