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In this paper, a new coding architecture is proposed for fiber-optic synchronous code division multiple access (S/CDMA) network by using parallel cancellation scheme and bit-stuffed unipolar m-sequence. The wellknown maximal length code (m-sequence) with one bit stuffing which is called bit-stuffed unipolar m-sequence in this paper can achieve unique cross-correlation value . Due to the uniqueness of cross-correlation value of unipolar m-sequence, the proposed parallel cancellation scheme can completely suppress the interuser interference in the negligible effects of noise. In the proposed architecture, the correlator employs avalanche photodiode (APD) for photodetection, and the correlator output can be modeled as a Gaussian random process [7][8]. In addition to the suppression of interuser interference, the inevitable effects of APD noise and thermal noise in the process of photodetection are also investigated in this paper.