Vibration-based secure side channel for medical devices
According to some embodiments, a system for securing communications between an implantable wearable medical device (IWMD) and an external device (ED) is disclosed. The system includes a wireless radio frequency (RF) channel configured for communication between the IWMD and the ED. The system further includes a vibration-based side channel configured for verifying communication between the IWMD and the ED such that the RF channel is activated only when the IWMD detects a vibration signal generated by an ED.
1. A system for securing communications between an implantable or wearable medical device (IWMD) and an external device (ED), the system comprising:
a wireless radio frequency (RF) channel configured to communicate medical information between the IWMD and the ED; and
a vibration-based side channel configured to verify the communication of medical information between the IWMD and the ED;
the RF channel being activated when the IWMD detects a vibration signal generated by the ED via a motion sensing device of the IWMD and determines an amplitude gradient and amplitude mean of the vibration signal are above respective thresholds via a demodulator of the IWMD.
2. The system of claim 1 , wherein the IWMD comprises a high-pass filter to eliminate vibration channel noise.
3. The system of claim 1 , wherein the IWMD and ED each comprise a RF module configured to transmit, receive, or transmit and receive the medical information.
4. The system of claim 1 , wherein the ED is a mobile device.
5. The system of claim 1 , wherein the ED comprises a modulator and vibration source for transmitting the vibration signal.
6. The system of claim 1 , wherein the ED comprises a speaker configured to generate a masking sound to mask the vibration signal.
7. The system of claim 1 , wherein the motion sensing device comprises an accelerometer.
8. The system of claim 1 , wherein an encryption key is transmitted through the vibration channel to the IWMD.
9. The system of claim 8 , wherein the medical information is encrypted when the IWMD receives the encryption key.
10. The system of claim 9 , wherein the IWMD performs a key reconciliation process when the encryption key includes one or more ambiguous bits.
11. A method for securing radio frequency (RF) communication of medical information between an implantable or wearable medical device (IWMD) and an external device (ED) via a vibration-based side channel, the method comprising the steps of:
activating the IWMD to detect a vibration signal;
placing the IWMD in a measurement mode when a vibration signal is detected;
high-pass filtering vibration signals below a predetermined frequency when the IWMD is in the measurement mode, the IWMD to return to a standby mode when no vibration signals above the predetermined frequency are detected; and
activating an RF channel for secure communication of the medical information when a vibration signal detected above the predetermined frequency has an amplitude gradient and amplitude mean above respective thresholds.
12. The method of claim 11 , further comprising receiving a vibration signal from an ED.
13. The method of claim 11 , further comprising masking the vibration signal.
14. The method of claim 11 , further comprising transmitting an encryption key through the vibration-based side channel.
15. The method of claim 14 , further comprising encrypting the medical information when the IWMD receives the transmitted encryption key.
16. The method of claim 15 , further comprising performing a key reconciliation process when the transmitted encryption key includes one or more ambiguous bits.
17. A non-transitory computer-readable medium having stored thereon a computer program for execution by a processor configured to perform a method of securing radio frequency (RF) communications between an implantable or wearable medical device (IWMD) and an external device (ED) via a vibration-based side channel, the method comprising:
activating the IWMD to detect a vibration signal;
placing the IWMD in a measurement mode when a vibration signal is detected;
high-pass filtering vibration signals below a predetermined frequency when the IWMD is in the measurement mode, the IWMD to return to a standby mode when no vibration signals above the predetermined frequency are detected; and
activating an RF channel for secure communication when a vibration signal detected above the predetermined frequency has an amplitude gradient and amplitude mean above respective thresholds.