Physical layer security enhanced system with novel LDPC decoder and artificial noise

摘要

Physical layer security is one of the most important issues in the design of communication system, especially in the scenario of wireless communication where the information transmission is exposed to the risk of eavesdropping. Previous works focus on the physical layer security by information scrambling and Low Density Parity Check (LDPC) coding. However, most of these works consider less the impact of physical layer security design on the performance of LDPC decoding, which may impair the system reliability. In this paper, we propose a new physical layer security enhanced system. A novel artificial noise is proposed to enhance the physical layer security of the system by worsening the wiretap channel, while an effective LDPC decoder based on tree structure of expectation propagation is proposed to guarantee the system reliability by solving the loop of decoding errors. Simulation results demonstrate that the proposed system is effective in enhancing the physical layer security with the improved reliability than the traditional systems.