Abstract: A new class of codes for synchronous SAC OCDMA system was designed, the error rate cause by multiple access interference is 0. The codes’ cross-correlation is one, defined the code weight and the number of users can get the shorter code length. Using the OptiSys7.0 to system simulation, analysis and comparison with the wavelength division multiplexer and the fiber grating as the codecs in different systems, in considering with the shot noise, phase induced intensity noise (PIIN) and thermal noise, analyzed the signal to noise ratio and bit error rate according to the characteristic of the codes and compared with the existing SAC codes. The results showed that: the SAC system with the codes has clear eye diagram, in the bit error rate, codec implementation and system performance has been greatly improved.

Key words: optical communication, optical code division multiple access, spectral-amplitude-coding, First One Code, phase-induced intensity noise, the theory of balanced detection