An on-chip security guard based on zero-power authentication for implantable medical devices

In order to fight against severe risks of security and privacy for implantable medical devices, an on-chip security guard based on zero-power authentication is proposed and verified in this paper. The conception of `zero-power´ is realized by virtue of wireless power recovery instead of fetching power from primary battery. The security guard recovers both data and clock from external wireless signals based on amplitude shift keying pulse width modulation. It features a wireless data rate of 500 Kbps and no need for on-chip clock generator. The Hash encryption is adopted in authentication and features a 32-bit ALU to speed up the SHA-1 computation with an estimated peak power of about only 1 mW, which is affordable by wireless power recovery which has a capacity of several mW. FPGA and chip implementation verify the feasibility of this system.