{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T15:57:23Z","timestamp":1783785443872,"version":"3.55.0"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,9,8]],"date-time":"2021-09-08T00:00:00Z","timestamp":1631059200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Cannot be determined now","award":["000000"],"award-info":[{"award-number":["000000"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Pulsars, especially X-ray pulsars detectable for small-size detectors, are highly accurate natural clocks suggesting potential applications such as interplanetary navigation control. Due to various complex cosmic background noise, the original pulsar signals, namely photon sequences, observed by detectors have low signal-to-noise ratios (SNRs) that obstruct the practical uses. This paper presents the pulsar denoising strategy developed based on the variational mode decomposition (VMD) approach. It is actually the initial work of our interplanetary navigation control research. The original pulsar signals are decomposed into intrinsic mode functions (IMFs) via VMD, by which the Gaussian noise contaminating the pulsar signals can be attenuated because of the filtering effect during signal decomposition and reconstruction. Comparison experiments based on both simulation and HEASARC-archived X-ray pulsar signals are carried out to validate the effectiveness of the proposed pulsar denoising strategy.<\/jats:p>","DOI":"10.3390\/e23091181","type":"journal-article","created":{"date-parts":[[2021,9,8]],"date-time":"2021-09-08T10:12:03Z","timestamp":1631095923000},"page":"1181","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["X-ray Pulsar Signal Denoising Based on Variational Mode Decomposition"],"prefix":"10.3390","volume":"23","author":[{"given":"Qiang","family":"Chen","sequence":"first","affiliation":[{"name":"School of Automation Science and Electrical Engineering, Beihang University (BUAA), Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Automation Science and Electrical Engineering, Beihang University (BUAA), Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lixia","family":"Yan","sequence":"additional","affiliation":[{"name":"School of Automation Science and Electrical Engineering, Beihang University (BUAA), Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.actaastro.2015.09.018","article-title":"Denoising of X-ray pulsar observed profile in the undecimated wavelet domain","volume":"118","author":"Xue","year":"2016","journal-title":"Acta Astronaut."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"066901","DOI":"10.1088\/0034-4885\/77\/6\/066901","article-title":"The surprising crab pulsar and its nebula: A review","volume":"77","author":"Buhler","year":"2014","journal-title":"Rep. 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