Investigation of ECG signal suitability for key generation to secure body area sensor networks

Abstract

Remote patient monitoring (RPM) systems help to continuously monitor the health condition of people affected by chronic diseases. The proposed research work analyses the suitability of ECG signals for 128-bit cryptographic key generation in RPM systems. The randomness and distinctiveness of keys generated from the ECG signal using the following three methods are evaluated. (a) The Inter Pulse Intervals (IPI) of the ECG signal captured from the patient's body are converted to a 128-bit binary sequence using modular encoding. (b) Short-time Fourier transform (STFT) is applied over the ECG signal and the key is generated using the features extracted from ECG signal. (c) The binary sequence obtained with the help of STFT features of ECG signal is partitioned into subkeys and transformed into a 128-bit binary sequence using Tiny Encryption Algorithm (TEA). The results illustrate that the ECG signal can generate a highly random and distinctive 128-bit cryptographic key.