{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:19:39Z","timestamp":1760239179063,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2020,9,27]],"date-time":"2020-09-27T00:00:00Z","timestamp":1601164800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China Innovation Group","award":["61521091"],"award-info":[{"award-number":["61521091"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61771030"],"award-info":[{"award-number":["61771030"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Global Navigation Satellite System Reflectometry (GNSS-R) technology is a new and promising remote sensing technology, especially satellite-based GNSS-R remote sensing, which has broad application prospects. In this work, the ionospheric impacts on space-borne GNSS-R sea surface altimetry were investigated. An analysis of optimal values for spatial filtering to remove ionospheric delays in space-borne GNSS-R altimetry was conducted. Considering that there are few satellite-borne GNSS-R orbit observations to date, simulated high-resolution space-borne GNSS-R orbital data were used for a comprehensive global and applicable study. The curves of absolute bias in relation to the bilateral filtering points were verified to achieve the minimum absolute bias. The optimal filtering points were evaluated in both statistical probability density and quantile analysis to show the reliability of the selected values. The proposed studies are helpful and valuable for the future implementation of high-accuracy space-borne GNSS-R sea surface altimetry.<\/jats:p>","DOI":"10.3390\/s20195535","type":"journal-article","created":{"date-parts":[[2020,9,28]],"date-time":"2020-09-28T08:02:58Z","timestamp":1601280178000},"page":"5535","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Space-Borne GNSS-R Ionospheric Delay Error Elimination by Optimal Spatial Filtering"],"prefix":"10.3390","volume":"20","author":[{"given":"Qiuyang","family":"Zhang","sequence":"first","affiliation":[{"name":"School of Instrumentation and Opto-Electronic Engineering, Beihang University, Beijing 100191, China"}]},{"given":"Yang","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Instrumentation and Opto-Electronic Engineering, Beihang University, Beijing 100191, China"}]},{"given":"Junming","family":"Xia","sequence":"additional","affiliation":[{"name":"National Space Science Center, Chinese Academy of Science, Beijing 1001901, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1728","DOI":"10.1109\/PROC.1968.6718","article-title":"Relationship between slope probability density function and the physical optics integral in rough surface scattering","volume":"56","author":"Barrick","year":"1968","journal-title":"Proc. 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