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To simultaneously support multimedia services with different signaling rates and quality-of-service requirements in optical code division multiple access (CDMA) networks, a new class of multilength, constant-weight optical orthogonal codes (OOCs) with good correlation properties is constructed algebraically in this paper. The performance of these new OOCs in an optical CDMA system with double-media services is analyzed. In contrast to conventional CDMA, our study shows that the performance of these multilength OOCs worsens as the code length increases, allowing prioritization in optical CDMA. Finally, an application of these multilength OOCs to integrate different types of multimedia services is briefly discussed

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In this paper, a novel code-shifting technique, which can be added atop asynchronous incoherent optical code-division multiple-access systems without complex modifications, is proposed and studied. The new technique divides the time-slot (or chips), in which the optical pulses of codewords are located, into g equal-width sub-chips; every pulse is randomly and independently shifted to start at one of the g sub-chips of its own chip, where g > 1 is a positive integer. The effects of this random g-shift to the cross-correlation property and performance of asynchronous optical codes (of periodic crosscorrelation functions of at most one) are formulated. Although it is found that the periodic cross-correlation functions are worsened to 3 − 2/g, our theoretical and computer-simulation results show an unconventional finding that code performance improves as g increases.