Abstract
In this study, the use of ECG data in the field of secure communication was examined by using a chaotic encryption method that has proven its reliability in the literature. ECG data, the chaoticity of which is a controversial issue in the literature, was used directly instead of chaotic number sequences in this method, and a security analysis was made over the NPCR, UACI, and entropy values of the encrypted images. While NPCR and UACI values indicate the security of the system against plaintext attacks by revealing the dissimilarity rate at the pixel level between two images encrypted with different keys, the entropy value indicates the encryption performance by giving information about how close the encrypted image is to the random appearance. In addition, phase portraits and Lyapunov exponents were examined, and the chaotic components in ECG were shown. According to the results, it has been observed that the sequence of numbers obtained by determining the person, the phase shift samples count, and the time of ECG taken can be used as the key with this method. In addition to the periodicity of healthy ECG data, the chaotic properties it contains have been shown to be sufficient for encryption applications.