{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T16:55:32Z","timestamp":1774716932945,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2022,7,13]],"date-time":"2022-07-13T00:00:00Z","timestamp":1657670400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Higher Education Malaysia","award":["FRGS\/1\/2018\/SKK06\/UNIMAP\/02\/1"],"award-info":[{"award-number":["FRGS\/1\/2018\/SKK06\/UNIMAP\/02\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ultra-wideband radar application for sleep breathing monitoring is hampered by the difficulty of obtaining breathing signals for non-stationary subjects. This occurs due to imprecise signal clutter removal and poor body movement removal algorithms for extracting accurate breathing signals. Therefore, this paper proposed a Sleep Breathing Detection Algorithm (SBDA) to address this challenge. First, SBDA introduces the combination of variance feature with Discrete Wavelet Transform (DWT) to tackle the issue of clutter signals. This method used Daubechies wavelets with five levels of decomposition to satisfy the signal-to-noise ratio in the signal. Second, SBDA implements a curve fit based sinusoidal pattern algorithm for detecting periodic motion. The measurement was taken by comparing the R-square value to differentiate between chest and body movements. Last but not least, SBDA applied the Ensemble Empirical Mode Decomposition (EEMD) method for extracting breathing signals before transforming the signal to the frequency domain using Fast Fourier Transform (FFT) to obtain breathing rate. The analysis was conducted on 15 subjects with normal and abnormal ratings for sleep monitoring. All results were compared with two existing methods obtained from previous literature with Polysomnography (PSG) devices. The result found that SBDA effectively monitors breathing using IR-UWB as it has the lowest average percentage error with only 6.12% compared to the other two existing methods from past research implemented in this dataset.<\/jats:p>","DOI":"10.3390\/s22145249","type":"journal-article","created":{"date-parts":[[2022,7,14]],"date-time":"2022-07-14T00:12:40Z","timestamp":1657757560000},"page":"5249","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Non-Contact Breathing Monitoring Using Sleep Breathing Detection Algorithm (SBDA) Based on UWB Radar Sensors"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7319-4916","authenticated-orcid":false,"given":"Muhammad","family":"Husaini","sequence":"first","affiliation":[{"name":"Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis (UniMAP), Arau 02600, Perlis, Malaysia"},{"name":"Advanced Sensor Technology, Centre of Exellence (CEASTech), Universiti Malaysia Perlis (UniMAP), Arau 02600, Perlis, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2547-3934","authenticated-orcid":false,"given":"Latifah Munirah","family":"Kamarudin","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis (UniMAP), Arau 02600, Perlis, Malaysia"},{"name":"Advanced Sensor Technology, Centre of Exellence (CEASTech), Universiti Malaysia Perlis (UniMAP), Arau 02600, Perlis, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7108-215X","authenticated-orcid":false,"given":"Ammar","family":"Zakaria","sequence":"additional","affiliation":[{"name":"Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis (UniMAP), Arau 02600, Perlis, Malaysia"},{"name":"Centre of Advanced Sensor and Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6208-6001","authenticated-orcid":false,"given":"Intan Kartika","family":"Kamarudin","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology Head and Neck Surgery, Universiti Teknologi MARA, Shah Alam 47000, Selangor, Malaysia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8336-8510","authenticated-orcid":false,"given":"Muhammad Amin","family":"Ibrahim","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Universiti Teknologi MARA, Shah Alam 47000, Selangor, Malaysia"}]},{"given":"Hiromitsu","family":"Nishizaki","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, University of Yamanashi, Kofu 400-8511, Yamanashi, Japan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5897-7573","authenticated-orcid":false,"given":"Masahiro","family":"Toyoura","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, University of Yamanashi, Kofu 400-8511, Yamanashi, Japan"}]},{"given":"Xiaoyang","family":"Mao","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, University of Yamanashi, Kofu 400-8511, Yamanashi, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"492","DOI":"10.1378\/chest.118.2.492","article-title":"Patients readmitted to ICUs: A systematic review of risk factors and outcomes","volume":"118","author":"Rosenberg","year":"2000","journal-title":"Chest"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1111\/j.1365-2044.2005.04186.x","article-title":"A physiologically-based early warning score for ward patients: The association between score and outcome","volume":"60","author":"Goldhill","year":"2005","journal-title":"Anaesthesia"},{"key":"ref_3","first-page":"23","article-title":"Respiratory Rate and Breathing Pattern","volume":"10","author":"Yuan","year":"2013","journal-title":"McMaster Univ. 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