{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T15:16:14Z","timestamp":1784301374092,"version":"3.55.0"},"reference-count":36,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,5,22]],"date-time":"2023-05-22T00:00:00Z","timestamp":1684713600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31971781"],"award-info":[{"award-number":["31971781"]}],"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":["ZR2021MD082"],"award-info":[{"award-number":["ZR2021MD082"]}],"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":["SAST2020-075"],"award-info":[{"award-number":["SAST2020-075"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Natural Science Foundation Project of Shandong Province","award":["31971781"],"award-info":[{"award-number":["31971781"]}]},{"name":"Natural Science Foundation Project of Shandong Province","award":["ZR2021MD082"],"award-info":[{"award-number":["ZR2021MD082"]}]},{"name":"Natural Science Foundation Project of Shandong Province","award":["SAST2020-075"],"award-info":[{"award-number":["SAST2020-075"]}]},{"DOI":"10.13039\/501100019082","name":"Shanghai Aerospace Science and Technology Innovation Fund","doi-asserted-by":"publisher","award":["31971781"],"award-info":[{"award-number":["31971781"]}],"id":[{"id":"10.13039\/501100019082","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019082","name":"Shanghai Aerospace Science and Technology Innovation Fund","doi-asserted-by":"publisher","award":["ZR2021MD082"],"award-info":[{"award-number":["ZR2021MD082"]}],"id":[{"id":"10.13039\/501100019082","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100019082","name":"Shanghai Aerospace Science and Technology Innovation Fund","doi-asserted-by":"publisher","award":["SAST2020-075"],"award-info":[{"award-number":["SAST2020-075"]}],"id":[{"id":"10.13039\/501100019082","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Global navigation satellite system reflectometry (GNSS-R) is a remote sensing technology of soil moisture measurement using signals of opportunity from GNSS, which has the advantages of low cost, all-weather detection, and multi-platform application. An in situ GNSS-R and radiometer fusion soil moisture retrieval model based on LSTM (long\u2013short term memory) is proposed to improve accuracy and robustness as to the impacts of vegetation cover and soil surface roughness. The Oceanpal GNSS-R data obtained from the experimental campaign at the Valencia Anchor Station are used as the main input data, and the TB (brightness temperature) and TR (soil roughness and vegetation integrated attenuation coefficient) outputs of the ELBARA-II radiometer are used as auxiliary input data, while field measurements with a Delta-T ML2x ThetaProbe soil moisture sensor were used for reference and validation. The results show that the LSTM model can be used to retrieve soil moisture, and that it performs better in the data fusion scenario with GNSS-R and radiometer. The STD of the multi-satellite fusion model is 0.013. Among the single-satellite models, PRN13, 20, and 32 gave the best retrieval results with STD = 0.011, 0.012, and 0.007, respectively.<\/jats:p>","DOI":"10.3390\/rs15102693","type":"journal-article","created":{"date-parts":[[2023,5,23]],"date-time":"2023-05-23T01:36:48Z","timestamp":1684805808000},"page":"2693","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["In-Situ GNSS-R and Radiometer Fusion Soil Moisture Retrieval Model Based on LSTM"],"prefix":"10.3390","volume":"15","author":[{"given":"Tianlong","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Information Science and Engineering, Shandong Agricultural University, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5702-5474","authenticated-orcid":false,"given":"Lei","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Information Science and Engineering, University of Jinan, Jinan 250022, China"},{"name":"Shandong Provincial Key Laboratory of Network-Based Intelligent Computing, Jinan 250022, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongtao","family":"Nan","sequence":"additional","affiliation":[{"name":"Beijing Institute of Spacecraft System Engineering, Beijing 100094, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cong","family":"Yin","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Sciences (NSSC\/CAS), Beijing 100190, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bo","family":"Sun","sequence":"additional","affiliation":[{"name":"College of Information Science and Engineering, Shandong Agricultural University, Tai\u2019an 271018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dongkai","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuebao","family":"Hong","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2044-2194","authenticated-orcid":false,"given":"Ernesto","family":"Lopez-Baeza","sequence":"additional","affiliation":[{"name":"Environmental Remote Sensing Group (Climatology from Satellites), Earth Physics & Thermodynamics Department, Faculty of Physics, University of Valencia, 46100 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/0034-4257(91)90013-V","article-title":"Applications of microwave remote sensing of soil moisture for water resources and agriculture","volume":"35","author":"Engman","year":"1991","journal-title":"Remote Sens. 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