{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T17:05:51Z","timestamp":1776186351031,"version":"3.50.1"},"reference-count":53,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,20]],"date-time":"2021-02-20T00:00:00Z","timestamp":1613779200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2018YFC1503705"],"award-info":[{"award-number":["2018YFC1503705"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41974129"],"award-info":[{"award-number":["41974129"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the special fund of Key Laboratory of Geo-Exploration Instruments, Ministry of Education","award":["3S2190230537"],"award-info":[{"award-number":["3S2190230537"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>As one of the main payloads mounted on the Yutu-2 rover of Chang\u2019E-4 probe, lunar penetrating radar (LPR) aims to map the subsurface structure in the Von K\u00e1rm\u00e1n crater. The field LPR data are generally masked by clutters and noises of large quantities. To solve the noise interference, dozens of filtering methods have been applied to LPR data. However, these methods have their limitations, so noise suppression is still a tough issue worth studying. In this article, the denoising convolutional neural network (CNN) framework is applied to the noise suppression and weak signal extraction of 500 MHz LPR data. The results verify that the low-frequency clutters embedded in the LPR data mainly came from the instrument system of the Yutu rover. Besides, compared with the classic band-pass filter and the mean filter, the CNN filter has better performance when dealing with noise interference and weak signal extraction; compared with Kirchhoff migration, it can provide original high-quality radargram with diffraction information. Based on the high-quality radargram provided by the CNN filter, the subsurface sandwich structure is revealed and the weak signals from three sub-layers within the paleo-regolith are extracted.<\/jats:p>","DOI":"10.3390\/rs13040779","type":"journal-article","created":{"date-parts":[[2021,2,21]],"date-time":"2021-02-21T21:15:01Z","timestamp":1613942101000},"page":"779","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Application of Denoising CNN for Noise Suppression and Weak Signal Extraction of Lunar Penetrating Radar Data"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1887-3171","authenticated-orcid":false,"given":"Haoqiu","family":"Zhou","sequence":"first","affiliation":[{"name":"College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China"},{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7451-9145","authenticated-orcid":false,"given":"Xuan","family":"Feng","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China"},{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"},{"name":"Key Laboratory of Geophysical Exploration Equipment, Ministry of Education, Jilin University, Changchun 130026, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5196-987X","authenticated-orcid":false,"given":"Zejun","family":"Dong","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China"},{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"}]},{"given":"Cai","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China"},{"name":"Key Laboratory of Geophysical Exploration Equipment, Ministry of Education, Jilin University, Changchun 130026, China"}]},{"given":"Wenjing","family":"Liang","sequence":"additional","affiliation":[{"name":"College of Geo-Exploration Science and Technology, Jilin University, Changchun 130026, China"},{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4229","DOI":"10.1038\/s41467-019-12278-3","article-title":"Descent trajectory reconstruction and landing site positioning of Chang\u2019E-4 on the lunar farside","volume":"10","author":"Liu","year":"2019","journal-title":"Nat. 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