{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T18:17:05Z","timestamp":1788459425898,"version":"build-2803163510"},"reference-count":30,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T00:00:00Z","timestamp":1788393600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Heart rate and cardiac dynamics can be monitored using several physiological signals, each with its own biophysical basis and signal characteristics. However, while individual properties of electrocardiogram (ECG), phonocardiogram (PCG), seismocardiogram (SCG), photoplethysmogram (PPG), and piezoplethysmogram (PiPG) are documented, systematic cross-modal comparisons remain scarce. This study aims to consolidate both the time and frequency domain features of these widely accessible technologies to provide practical guidelines for signal processing and multimodal integration. We simultaneously recorded ECG, PCG, SCG, PPG, and PiPG under standardized resting conditions and aligned all modalities on the ECG R-peak. Results highlight clear consistencies (e.g., reproducible morphology and spectra for ECG, PPG, and PiPG) as well as higher variability in PCG and SCG due to sensor coupling and anatomical factors. Temporal latencies relative to the ECG confirm known physiological conduction delays, while frequency analysis identifies modality-specific bands:\u2009~\u200930 Hz for PCG, 11\u201314 Hz for SCG, and 1\u20132 Hz for PPG\/PiPG. Bandwidth analysis further emphasizes differences in spectral richness across modalities. By presenting these benchmarks in a unified framework, this work addresses the current gap between isolated characterizations and integrated signal knowledge. The outcome is a reference dataset and interpretation map that can guide filtering strategies, feature extraction, and the design of multimodal cardiac monitoring systems.<\/jats:p>","DOI":"10.1371\/journal.pone.0357922","type":"journal-article","created":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T17:37:32Z","timestamp":1788457052000},"page":"e0357922","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Time and frequency characteristics of various noninvasive heartbeat sensors"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5986-3415","authenticated-orcid":true,"given":"Pierre","family":"Charlier","sequence":"first","affiliation":[{"name":"CHU Lille, Inserm, CIC 1403 - Centre d\u2019investigation clinique","place":["Lille, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3400-5788","authenticated-orcid":true,"given":"Mathieu","family":"Jeanne","sequence":"additional","affiliation":[{"name":"CHU Lille, Inserm, CIC 1403 - Centre d\u2019investigation clinique","place":["Lille, France"]},{"name":"CHU de Lille","place":["Lille, France"],"department":["CHU Lille, Department of Anesthesiology and Critical Care"]},{"name":"University of Lille, ULR 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associ\u00e9es, University of Lille","place":["Lille, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8545-9923","authenticated-orcid":true,"given":"Maxence","family":"Hureau","sequence":"additional","affiliation":[{"name":"CHU Lille, Inserm, CIC 1403 - Centre d\u2019investigation clinique","place":["Lille, France"]},{"name":"CHU de Lille","place":["Lille, France"],"department":["CHU Lille, Department of Anesthesiology and Critical Care"]},{"name":"University of Lille, ULR 7365 - GRITA - Groupe de Recherche sur les formes Injectables et les Technologies Associ\u00e9es, University of Lille","place":["Lille, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3727-9434","authenticated-orcid":true,"given":"Julien","family":"De Jonckheere","sequence":"additional","affiliation":[{"name":"CHU Lille, Inserm, CIC 1403 - Centre d\u2019investigation clinique","place":["Lille, France"]},{"name":"University of Lille, ULR 2694 \u2013 METRICS","place":["Lille, France"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,9,3]]},"reference":[{"key":"pone.0357922.ref001","first-page":"801191","article-title":"Optimal wavelength selection for noncontact reflection photoplethysmography.","author":"LF Corral Martinez","year":"2011","journal-title":"Puebla, Mexico"},{"issue":"3","key":"pone.0357922.ref002","doi-asserted-by":"crossref","first-page":"230","DOI":"10.1109\/TBME.1985.325532","article-title":"A real-time QRS detection algorithm","volume":"32","author":"J Pan","year":"1985","journal-title":"IEEE Trans Biomed Eng"},{"issue":"6","key":"pone.0357922.ref003","doi-asserted-by":"crossref","first-page":"3119","DOI":"10.1109\/JSEN.2014.2357257","article-title":"Recent Advances in Wearable Sensors for Health Monitoring","volume":"15","author":"MM Rodgers","year":"2015","journal-title":"IEEE Sensors J"},{"key":"pone.0357922.ref004","doi-asserted-by":"crossref","first-page":"103146","DOI":"10.1016\/j.dsp.2021.103146","article-title":"A survey on edge computing for wearable technology","volume":"125","author":"X Jin","year":"2022","journal-title":"Digital Signal Processing"},{"issue":"4","key":"pone.0357922.ref005","doi-asserted-by":"crossref","first-page":"743","DOI":"10.1007\/s10877-019-00382-0","article-title":"Comparison of multiple cardiac signal acquisition technologies for heart rate variability analysis","volume":"34","author":"P Charlier","year":"2020","journal-title":"J Clin Monit Comput"},{"key":"pone.0357922.ref006","doi-asserted-by":"crossref","first-page":"258","DOI":"10.3389\/fpubh.2017.00258","article-title":"An Overview of Heart Rate Variability Metrics and Norms","volume":"5","author":"F Shaffer","year":"2017","journal-title":"Front Public Health"},{"issue":"10","key":"pone.0357922.ref007","doi-asserted-by":"crossref","DOI":"10.1161\/CIRCULATIONAHA.108.191095","article-title":"AHA\/ACCF\/HRS recommendations for the standardization and interpretation of the electrocardiogram: part III: intraventricular conduction disturbances: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; 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