AmpRmdr: Remainder-Based Secret Key Generation Using Wireless Channel Amplitude

Physical layer secret key generation is a promising technique to share secret keys among legitimate users, where channel amplitude is widely used as it can be easily obtained. However, the secret key generation using channel amplitude suffers from less randomness and nearby attacks. To tackle these problems, this paper proposes a remainder-based secret key generation scheme using channel amplitude. By using the modulo operation, the remainder of a random variable tends to be uniformly distributed. Moreover, the modulo operation can enlarge the difference between two correlated variables. For the proposed scheme, we derive the distribution of the channel amplitude and calculate the statistical error probability of the generated secret keys. Finally, we use the simulation results to verify the effectiveness of the proposed remainder-based secret key generation scheme and convince it on the ZigBee platform.