{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T05:25:43Z","timestamp":1770009943420,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,9,14]],"date-time":"2024-09-14T00:00:00Z","timestamp":1726272000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico (TecNM)","award":["20133.24-P"],"award-info":[{"award-number":["20133.24-P"]}]},{"name":"Tecnol\u00f3gico Nacional de M\u00e9xico (TecNM)","award":["20586.24-P"],"award-info":[{"award-number":["20586.24-P"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Protecting sensitive patient data, such as electrocardiogram (ECG) signals, during RF wireless transmission is essential due to the increasing demand for secure telemedicine communications. This paper presents an innovative chaotic-based encryption system designed to enhance the security and integrity of telemedicine data transmission. The proposed system utilizes a multi-scroll chaotic system for ECG signal encryption based on master\u2013slave synchronization. The ECG signal is encrypted by a master system and securely transmitted to a remote location, where it is decrypted by a slave system using an extended state observer. Synchronization between the master and slave is achieved through the Lyapunov criteria, which ensures system stability. The system also supports Orthogonal Frequency Division Multiplexing (OFDM) and adaptive n-quadrature amplitude modulation (n-QAM) schemes to optimize signal discretization. Experimental validations with a custom transceiver scheme confirmed the system\u2019s effectiveness in preventing channel overlap during 2.5 GHz transmissions. Additionally, a commercial RF Power Amplifier (RF-PA) for LTE applications and a development board were integrated to monitor transmission quality. The proposed encryption system ensures robust and efficient RF transmission of ECG data, addressing critical challenges in the wireless communication of sensitive medical information. This approach demonstrates the potential for broader applications in modern telemedicine environments, providing a reliable and efficient solution for the secure transmission of healthcare data.<\/jats:p>","DOI":"10.3390\/e26090787","type":"journal-article","created":{"date-parts":[[2024,9,16]],"date-time":"2024-09-16T11:36:37Z","timestamp":1726486597000},"page":"787","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Enhancing Security of Telemedicine Data: A Multi-Scroll Chaotic System for ECG Signal Encryption and RF Transmission"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5437-8215","authenticated-orcid":false,"given":"Jos\u00e9 Ricardo","family":"C\u00e1rdenas-Valdez","sequence":"first","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Tijuana, Tecnol\u00f3gico Nacional de M\u00e9xico, Tijuana 22435, Baja California, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9506-5613","authenticated-orcid":false,"given":"Ram\u00f3n","family":"Ram\u00edrez-Villalobos","sequence":"additional","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Tijuana, Tecnol\u00f3gico Nacional de M\u00e9xico, Tijuana 22435, Baja California, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-2454-8248","authenticated-orcid":false,"given":"Catherine","family":"Ramirez-Ubieta","sequence":"additional","affiliation":[{"name":"Instituto Tecnol\u00f3gico de Tijuana, Tecnol\u00f3gico Nacional de M\u00e9xico, Tijuana 22435, Baja California, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7994-9774","authenticated-orcid":false,"given":"Everardo","family":"Inzunza-Gonzalez","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda Arquitectura y Dise\u00f1o, Universidad Aut\u00f3noma de Baja California, Carret. Tijuana-Ensenada No. 3917, Ensenada 22860, Baja California, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.ejim.2018.04.014","article-title":"Human serum albumin in cardiovascular diseases","volume":"52","author":"Arques","year":"2018","journal-title":"Eur. J. Intern. Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2555","DOI":"10.1093\/eurheartj\/ehv305","article-title":"Pathophysiological role of oxidative stress in systolic and diastolic heart failure and its therapeutic implications","volume":"36","author":"Gori","year":"2015","journal-title":"Eur. Heart J."},{"key":"ref_3","first-page":"247","article-title":"Cardiovascular disease and COVID-19. Diabetes and Metabolic Syndrome","volume":"14","author":"Bansal","year":"2020","journal-title":"Clin. Res. 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