Performance Simulation Research On Optical Code Switching System And WDM-PON System Based On OCDM

Optical Code Division Multiplexing (OCDM) is a way that can achieve multi-user shared channel, random asynchronous access, high speed, transparent communication. It has many advantages such as large quantity codes, good security and strong anti-interference, etc. Comparing with other multiplexing technology, OCDM has incomparable advantage which make OCDM has a broad application prospect in high-speed optical fiber communication. Based on the advantages and characteristics of OCDM, the switching network and access network has been studied, which are in order to achieve all-optical switching and optical broadband access.The history and development of optical fiber communication network is reviewed and summarized at first, and then basic OCDM system and key technologies. On this basis, this paper has focused on the construction of OCDM code, analyzed the performance of OCDM code and compared several OCDM code.Based on the analysis of basic principle of OCDM code, the paper has proposed a novel all-optical switching network using OCDM code, which combines optical label switching (OLS) with OCDM technology. Unlike the traditional optical switching network, in this scheme, the OCDM label takes an implicit way, the data payload and optical label occupy the same wavelength, using the orthogonal relationship of OCDM codes route and switch the user information. After that,the all-optical switching network based OCDM label is setup and analyzed. Simulation result shows that data packet can be successfully identified and switched, the all-optical switching network is feasible.On the other hand, in the OCDM access network, OOK modulation has inevitable disadvantages limiting the development of OCDM access network. This paper proposes a new OCDM WDM PON system with DQPSK modulation and setup the simulation system. The security, system capacity, sensitivity of the receiver and noise tolerating ability is simulated and analyzed. The result shows that the OCDM WDM PON system with DQPSK has greater system capacity, better security performance, higher receiver sensitivity and better system noise immunity and so on.