{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T14:49:06Z","timestamp":1740149346862,"version":"3.37.3"},"reference-count":42,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T00:00:00Z","timestamp":1580169600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"By using multi-satellite observations of the L1 signal-to-noise ratio (SNR) from the Cyclone Global Navigation Satellite System (CYGNSS) taken in 2017, we present the occurrence of nighttime topside ionospheric irregularities in low-latitude and equatorial regions. The most significant finding of this study is the existence of longitudinal structures with a wavenumber 4 pattern in the topside irregularities. This suggests that lower atmospheric waves, especially a daytime diurnal eastward-propagating zonal wave number-3 nonmigrating tide (DE3), might play an important role in the generation of topside plasma bubbles during the low solar minimum. Observations of scintillation events indicate that the maximum occurrence of nighttime topside ionospheric irregularities occurs on the magnetic equator during the equinoxes. The current work, which could be regarded as an important update of the previous investigations, would be readily for the further global analysis of the topside ionospheric irregularities.<\/jats:p>","DOI":"10.3390\/s20030708","type":"journal-article","created":{"date-parts":[[2020,1,28]],"date-time":"2020-01-28T14:37:09Z","timestamp":1580222229000},"page":"708","source":"Crossref","is-referenced-by-count":3,"title":["Investigation of the Occurrence of Nighttime Topside Ionospheric Irregularities in Low-Latitude and Equatorial Regions Using CYGNSS Satellites"],"prefix":"10.3390","volume":"20","author":[{"given":"Liang","family":"Huang","sequence":"first","affiliation":[{"name":"Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Yi","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Qiong","family":"Tang","sequence":"additional","affiliation":[{"name":"Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Guanyi","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Zhuangkai","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2692-9451","authenticated-orcid":false,"given":"Chen","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Space Physics, School of Electronic Information, Wuhan University, Wuhan 430072, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"821","DOI":"10.1029\/RS011i010p00821","article-title":"Model of equatorial scintillation from in-situ measurements","volume":"11","author":"Basu","year":"1976","journal-title":"Radio Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5447","DOI":"10.1029\/JA081i031p05447","article-title":"Radar observations of F region equatorial irregularities","volume":"81","author":"Woodman","year":"1976","journal-title":"J. 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