A PHY-Based Secret Sharing Scheme in MEMO Systems

摘要

A secure secret sharing scheme distributes a secret among a group of participants and only when a sufficient number of shares are combined together can the secret be reconstructed. In this paper, we present a secure PHY-based secret sharing (PSS) scheme exploiting radio channel fading coefficients in multiple-input multiple-output (MIMO) systems, (n, n) threshold secret sharing scheme is considered and there is no need for the third party to distribute keys in PSS scheme. A two-step randomness sharing is designed, which reduces the time overhead significantly compared to one-by-one randomness sharing when the number of participants increases. Furthermore, we derive a power allocation scheme under power constraints based on particle swarm optimization (PSO) algorithm. Numerical results demonstrate the efficiency of our power allocation strategies on secret key rates.