The multi-layer secure communication system based on 2D-OCDMA coding

Abstract This paper presents a novel multi-layer secure communication system that bases 2D-OCDMA technology to enhance the security and number of users of the system. The system innovatively combines RSA encryption, polarization multiplexing, and address coding techniques to protect and transmit the data. At the transmitting end, the data is encrypted by algorithm and then encoded by address code. The encoded optical data is split into two orthogonal polarization states and sent over the same channel. At the receiving end, only the optical signals in the matching polarization state can be retrieved by the polarizer with the right angle. The retrieved data is then decoded by the address code and decrypted by the algorithm to recover the original data. This system achieves multi-layer security and capacity enhancement by processing the information at different layers. The feasibility of the system is demonstrated by joint experimental simulation using Java programming language and Optisystem simulation software. In this paper, low BER transmission of 4 code words for 8 users 50 km 1Gbit/s is realized using optical orthogonal codes (OOC) with BER around 10−30. It realizes the enhancement of 4-user to 8-user without affecting the transmission effect.