{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:09:37Z","timestamp":1760231377012,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2022,9,14]],"date-time":"2022-09-14T00:00:00Z","timestamp":1663113600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"],"award-info":[{"award-number":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"]}]},{"name":"Chinese Academy of Sciences (CAS) programs of \u201cYouth Innovation Promotion Association\u201d","award":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"],"award-info":[{"award-number":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"]}]},{"name":"Western young scholars","award":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"],"award-info":[{"award-number":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"]}]},{"name":"China Postdoctoral Science Foundation","award":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"],"award-info":[{"award-number":["11903040","41674034","41974032","42030105","2022414","XAB2019B21","2020M683763"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Chinese BeiDou global satellite system (BDS-3) and regional system (BDS-2) are predicted to coexist over the next decade. Intersystem biases (ISBs) in BDS-2\/BDS-3 play a key role in maintaining the consistency and continuity from the BDS-2 to BDS-3 time transfer. Here, we discuss the temporal characteristics, parameter composition, generation mechanism, and the effect of ISBs in BDS-2\/BDS-3 on time and frequency transfer. The satellite orbits and clock products from three international GNSS service analysis centers, namely Wuhan University (WUM, China), GeoForschungsZentrum Potsdam (GFZ, Germany), and the Center for Orbit Determination in Europe (CODE), were employed to investigate the time-transfer stability of ISBs when BDS-2 and BDS-3 were used in combination. We analyzed the intrinsic characteristics of ISBs, the receiver types, antennas, and frequency standards. Our first results showed that ISBs are stable for different analysis center products, although the mean values of daily results differed markedly for the three analysis centers. With respect to the relationship between station attribution and ISB difference for a time link, the receiver type, antenna, and frequency standard influence the ISB differences in time and frequency transfer. The effect of three ISB stochastic models was evaluated with respect to time and frequency transfer. The \u201cwalk\u201d and \u201cconstant\u201d schemes were slightly superior to \u201cnoise\u201d, with the improvement in their frequency stability being approximately 5% compared with that of \u201cnoise\u201d.<\/jats:p>","DOI":"10.3390\/rs14184594","type":"journal-article","created":{"date-parts":[[2022,9,14]],"date-time":"2022-09-14T23:16:36Z","timestamp":1663197396000},"page":"4594","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Preliminary Analysis of Intersystem Biases in BDS-2\/BDS-3 Precise Time and Frequency Transfer"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9991-9310","authenticated-orcid":false,"given":"Pengfei","family":"Zhang","sequence":"first","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"Key Laboratory of Time and Frequency Primary Standards, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Yu Quan Road, Beijing 100049, China"},{"name":"State Key Laboratory of Geo-information Engineering, Xi\u2019an Research Institute of Surveying and Mapping, Xi\u2019an 710054, China"}]},{"given":"Rui","family":"Tu","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Yu Quan Road, Beijing 100049, China"},{"name":"Key Laboratory of Precision Navigation Positioning and Timing Technology, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]},{"given":"Linlin","family":"Tao","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Yu Quan Road, Beijing 100049, China"}]},{"given":"Bing","family":"Wang","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Yu Quan Road, Beijing 100049, China"}]},{"given":"Yuping","family":"Gao","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"Key Laboratory of Time and Frequency Primary Standards, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Yu Quan Road, Beijing 100049, China"}]},{"given":"Xiaochun","family":"Lu","sequence":"additional","affiliation":[{"name":"National Time Service Center, Chinese Academy of Sciences, Xi\u2019an 710600, China"},{"name":"University of Chinese Academy of Sciences, Yu Quan Road, Beijing 100049, China"},{"name":"Key Laboratory of Precision Navigation Positioning and Timing Technology, Chinese Academy of Sciences, Xi\u2019an 710600, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"56","DOI":"10.1007\/s10291-019-0847-x","article-title":"Performance of BDS-3: Satellite visibility and dilution of precision","volume":"23","author":"Wang","year":"2019","journal-title":"GPS Solut."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s43020-019-0006-0","article-title":"Basic performance and future developments of BeiDou global navigation satellite system","volume":"1","author":"Yang","year":"2020","journal-title":"Satell. 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