{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T19:29:49Z","timestamp":1776281389649,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2024,12,11]],"date-time":"2024-12-11T00:00:00Z","timestamp":1733875200000},"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":["2021YFC3090203"],"award-info":[{"award-number":["2021YFC3090203"]}]},{"name":"National Key R&amp;D Program of China","award":["SCSF202205"],"award-info":[{"award-number":["SCSF202205"]}]},{"name":"National Key R&amp;D Program of China","award":["NMICJY202304"],"award-info":[{"award-number":["NMICJY202304"]}]},{"name":"Hainan Province South China Sea Meteorological Disaster Prevention and Reduction Key Laboratory","award":["2021YFC3090203"],"award-info":[{"award-number":["2021YFC3090203"]}]},{"name":"Hainan Province South China Sea Meteorological Disaster Prevention and Reduction Key Laboratory","award":["SCSF202205"],"award-info":[{"award-number":["SCSF202205"]}]},{"name":"Hainan Province South China Sea Meteorological Disaster Prevention and Reduction Key Laboratory","award":["NMICJY202304"],"award-info":[{"award-number":["NMICJY202304"]}]},{"name":"National Meteorological Information Center surplus fund project","award":["2021YFC3090203"],"award-info":[{"award-number":["2021YFC3090203"]}]},{"name":"National Meteorological Information Center surplus fund project","award":["SCSF202205"],"award-info":[{"award-number":["SCSF202205"]}]},{"name":"National Meteorological Information Center surplus fund project","award":["NMICJY202304"],"award-info":[{"award-number":["NMICJY202304"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This study investigates the application of an improved multi-threshold method based on the K-means algorithm for clutter filtering in W-band cloud and fog radar observations. Utilizing W-band millimeter-wave cloud and fog radar data collected from March to July 2023 in the Qingdao area, a dataset of cloud and fog echo of different types was constructed and statistically analyzed. Subsequently, a multi-threshold clutter filtering method was proposed to identify and eliminate abnormal interferences such as noise spikes, radial interference, and suspended matter clutter. This method employs the basic data and spatiotemporal information from the cloud radar as feature variables for K-means clustering and dynamically adjusts thresholds based on the clustering results. The clutter-filtered data were further used for the verification analysis of cloud and fog identification. The results demonstrate that the proposed multi-threshold method effectively removes clutter and significantly reduces its impact on cloud and fog echo under weather conditions of clouds, fog, and coexisting cloud\u2013fog, while controlling the loss of cloud and fog echo within the required accuracy range.<\/jats:p>","DOI":"10.3390\/rs16244640","type":"journal-article","created":{"date-parts":[[2024,12,11]],"date-time":"2024-12-11T06:44:05Z","timestamp":1733899445000},"page":"4640","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["An Improved Multi-Threshold Clutter Filtering Algorithm for W-Band Cloud Radar Based on K-Means Clustering"],"prefix":"10.3390","volume":"16","author":[{"given":"Zhao","family":"Shi","sequence":"first","affiliation":[{"name":"College of Atmospheric Sounding, Chengdu University of Information Technology, Chengdu 610225, China"},{"name":"Key Laboratory of Atmospheric Sounding, China Meteorological Administration, Chengdu 610225, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-5229-2166","authenticated-orcid":false,"given":"Lingjiang","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Atmospheric Sounding, Chengdu University of Information Technology, Chengdu 610225, China"},{"name":"Key Laboratory of Atmospheric Sounding, China Meteorological Administration, Chengdu 610225, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fengyuan","family":"Wu","sequence":"additional","affiliation":[{"name":"College of Atmospheric Sounding, Chengdu University of Information Technology, Chengdu 610225, China"},{"name":"Key Laboratory of Atmospheric Sounding, China Meteorological Administration, Chengdu 610225, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong","family":"Lei","sequence":"additional","affiliation":[{"name":"Meteorological Observation Center of CMA, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huiying","family":"Wang","sequence":"additional","affiliation":[{"name":"National Meteorological Information Center of CMA, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiya","family":"Tang","sequence":"additional","affiliation":[{"name":"College of Atmospheric Sounding, Chengdu University of Information Technology, Chengdu 610225, China"},{"name":"Key Laboratory of Atmospheric Sounding, China Meteorological Administration, Chengdu 610225, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,11]]},"reference":[{"key":"ref_1","first-page":"378","article-title":"Millimeter-wave meteorological radar\u2019s capability in cloud measurement","volume":"3","author":"Wei","year":"1985","journal-title":"Acta Meteorol. 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