Chaotic encryption of real-time ECG signal in embedded system for secure telemedicine

Security in telemedicine has been of great interest in recent years due to the personal and confidential information that is used, since it is sent or stored through insecure channels, which generates a security problem such in telemetry, where biomedical signals (ECG, EEG, SpO2) are used for diagnosis of diseases. In this work, a chaos-based cryptographic algorithm is proposed using two-dimensional Badola map implemented in an embedded system based on a 32-bit microcontroller to provide confidentiality of biomedical signals such as the electrocardiogram for applications in low-cost secure embedded systems in telemedicine for monitoring or diagnosis. The electrocardiogram (ECG) signal is acquired in real-time through a medical ECG module, which allows us to measure the ECG signal directly of the patient in real-time. In addition, we propose to use a simple non-linear function over the ECG signal to increase considerably the sensitivity at plain biosignal in the encryption process. In experimental results, several security analyzes are presented such as key space, secret key sensitivity, clear signal sensitivity, histograms, correlation coefficient and encryption time. The results show that the proposed chaotic encryption algorithm is resistant against common attacks and it can be used in secure low-cost embedded systems for telemedicine applications.