关键词: MIMO技术, 格密码, 安全性, 选择性密文攻击

Abstract: The physical layer security of massive Multiple Input Multiple Output（MIMO） communications is researched in this paper. The scheme of MIMO cryptography based on lattices and OAEP + （Improved Optimal Asymmetric Encryption Padding） algorithm is proposed. Under the condition of appropriate restrictions, the problem of the eavesdropper’s decoding complexity for the massive MIMO system can be mapped to solve standard lattice problems. The proposed scheme, which uses the lattice-based cryptography and OAEP + algorithm, is believed to provide resistance against quantum computing attack and adaptive chosen ciphertext attack. Moreover, this scheme can be used to securely communicate without a pre-shared secret. The key management can be greatly simplified. The results of MatLab simulation show that the proposed scheme is feasible. By the way, the simulation results show that there is a strong linear relationship between the computational secrecy capacity of MIMO channel and the number of transmitting antennas under the lattice basis reduction algorithms.

Key words: Multiple Input Multiple Output（MIMO）, lattice-based cryptography, security, chosen ciphertext attack