{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T14:17:06Z","timestamp":1776953826110,"version":"3.51.4"},"reference-count":46,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2023,11,1]],"date-time":"2023-11-01T00:00:00Z","timestamp":1698796800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Zhejiang Leading Innovative and Entrepreneur Team Introduction Program","award":["2020R01005"],"award-info":[{"award-number":["2020R01005"]}]},{"name":"Zhejiang Leading Innovative and Entrepreneur Team Introduction Program","award":["10318A992001"],"award-info":[{"award-number":["10318A992001"]}]},{"name":"Zhejiang Leading Innovative and Entrepreneur Team Introduction Program","award":["2021C03002"],"award-info":[{"award-number":["2021C03002"]}]},{"name":"Westlake University","award":["2020R01005"],"award-info":[{"award-number":["2020R01005"]}]},{"name":"Westlake University","award":["10318A992001"],"award-info":[{"award-number":["10318A992001"]}]},{"name":"Westlake University","award":["2021C03002"],"award-info":[{"award-number":["2021C03002"]}]},{"name":"Zhejiang Key R&amp;D Program","award":["2020R01005"],"award-info":[{"award-number":["2020R01005"]}]},{"name":"Zhejiang Key R&amp;D Program","award":["10318A992001"],"award-info":[{"award-number":["10318A992001"]}]},{"name":"Zhejiang Key R&amp;D Program","award":["2021C03002"],"award-info":[{"award-number":["2021C03002"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A hypoglossal nerve stimulator (HGNS) is an invasive device that is used to treat obstructive sleep apnea (OSA) through electrical stimulation. The conventional implantable HGNS device consists of a stimuli generator, a breathing sensor, and electrodes connected to the hypoglossal nerve via leads. However, this implant is bulky and causes significant trauma. In this paper, we propose a minimally invasive HGNS based on an electrocardiogram (ECG) sensor and wireless power transfer (WPT), consisting of a wearable breathing monitor and an implantable stimulator. The breathing external monitor utilizes an ECG sensor to identify abnormal breathing patterns associated with OSA with 88.68% accuracy, achieved through the utilization of a convolutional neural network (CNN) algorithm. With a skin thickness of 5 mm and a receiving coil diameter of 9 mm, the power conversion efficiency was measured as 31.8%. The implantable device, on the other hand, is composed of a front-end CMOS power management module (PMM), a binary-phase-shift-keying (BPSK)-based data demodulator, and a bipolar biphasic current stimuli generator. The PMM, with a silicon area of 0.06 mm2 (excluding PADs), demonstrated a power conversion efficiency of 77.5% when operating at a receiving frequency of 2 MHz. Furthermore, it offers three-voltage options (1.2 V, 1.8 V, and 3.1 V). Within the data receiver component, a low-power BPSK demodulator was ingeniously incorporated, consuming only 42 \u03bcW when supplied with a voltage of 0.7 V. The performance was achieved through the implementation of the self-biased phase-locked-loop (PLL) technique. The stimuli generator delivers biphasic constant currents, providing a 5 bit programmable range spanning from 0 to 2.4 mA. The functionality of the proposed ECG- and WPT-based HGNS was validated, representing a highly promising solution for the effective management of OSA, all while minimizing the trauma and space requirements.<\/jats:p>","DOI":"10.3390\/s23218882","type":"journal-article","created":{"date-parts":[[2023,11,1]],"date-time":"2023-11-01T03:29:33Z","timestamp":1698809373000},"page":"8882","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Minimally Invasive Hypoglossal Nerve Stimulator Enabled by ECG Sensor and WPT to Manage Obstructive Sleep Apnea"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6570-0011","authenticated-orcid":false,"given":"Fen","family":"Xia","sequence":"first","affiliation":[{"name":"Zhejiang University, Hangzhou 310024, China"},{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6447-4211","authenticated-orcid":false,"given":"Hanrui","family":"Li","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"},{"name":"SAMA Labs, Computer, Electrical and Mathematical Science and Engineering (CEMSE) Division, Department of Electrical and Computer Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yixi","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Superlattices, Microstructures Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100045, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xing","family":"Liu","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4410-4106","authenticated-orcid":false,"given":"Yankun","family":"Xu","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chaoming","family":"Fang","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiming","family":"Hou","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Siyu","family":"Lin","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhao","family":"Zhang","sequence":"additional","affiliation":[{"name":"SAMA Labs, Computer, Electrical and Mathematical Science and Engineering (CEMSE) Division, Department of Electrical and Computer Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jie","family":"Yang","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4137-7272","authenticated-orcid":false,"given":"Mohamad","family":"Sawan","sequence":"additional","affiliation":[{"name":"CenBRAIN Laboratory, School of Engineering, Westlake University, Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"690","DOI":"10.1111\/resp.13838","article-title":"Global burden of sleep-disordered breathing and its implications","volume":"25","author":"Lyons","year":"2020","journal-title":"Respirology"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Xia, F., and Sawan, M. 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