{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T04:59:19Z","timestamp":1773723559352,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,5,24]],"date-time":"2020-05-24T00:00:00Z","timestamp":1590278400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R &amp; D Program of China","award":["2018YFC1407400"],"award-info":[{"award-number":["2018YFC1407400"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41704010"],"award-info":[{"award-number":["41704010"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection","award":["STKF201923"],"award-info":[{"award-number":["STKF201923"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Tide data plays a key role in many marine scientific research fields such as seafloor topography measurement and navigation safety. To obtain reliable tide data, various methods have been proposed, e.g., tide station measurement, satellite altimeter measurement, and differential global positioning system (GPS) buoy measurement. However, these methods suffer from the limitation that continuous observations at different areas might not be always available. In order to provide high-precision as well as continuous real-time tide data, we propose a method based on real-time precise point positioning (RT-PPP) by using International GNSS Service (IGS) real-time service (RTS) products. Firstly, compared with the IGS final products, the accuracy of the RTS satellite orbit and clock is evaluated. Secondly, the positioning performance of RT-PPP is compared with the IGS ultra-fast products. Finally, a robust Vondrak filter is proposed to eliminate the influence of high-frequency noise and errors and to obtain tide results. Experimental results show that three-dimensional (3D) accuracy of the RTS orbit is better than 0.05 m, and also has 0.22 ns less clock bias. An improvement of 60% is achieved for positioning accuracy using RTS products compared to IGS ultra-fast products. Compared with the post-processing PPP method, the double difference (DD) method and tide gauge data, the root mean square (RMS) values of RT-PPP tide are 0.090, 0.194 and 0.167 m, respectively.<\/jats:p>","DOI":"10.3390\/s20102968","type":"journal-article","created":{"date-parts":[[2020,5,25]],"date-time":"2020-05-25T11:42:02Z","timestamp":1590406922000},"page":"2968","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Evaluation of Real-Time PPP-Based Tide Measurement Using IGS Real-Time Service"],"prefix":"10.3390","volume":"20","author":[{"given":"Mingwei","family":"Di","sequence":"first","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anmin","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China"},{"name":"Tianjin Port Environmental Monitoring Engineering Center, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4042-8955","authenticated-orcid":false,"given":"Bofeng","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China"},{"name":"First Monitoring and Application Center, China Earthquake Administration, 7 Naihuo Road, Tianjin 300180, China"},{"name":"Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection, College of Resources and Environment, Linyi University, Linyi 276000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiali","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rongxia","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mengyuan","family":"Li","sequence":"additional","affiliation":[{"name":"School of Marine Science and Technology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/S0074-6142(01)80006-1","article-title":"Sea level change in the era of the recording tide gauge","volume":"Volume 75","author":"Douglas","year":"2001","journal-title":"International Geophysics"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1029\/2009JC005997","article-title":"Changes in extreme high water levels based on a quasi-global tide-gauge data set","volume":"115","author":"Menendez","year":"2010","journal-title":"J. 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