MWML-OOC multimedia optical CDMA using SOC

In the MWML (multiweight-multilength) - OOC (optical orthogonal code) optical code division multiple access (CDMA), the differentiation of the transmission rate and QoS (quality of service) can be realized by changing the code-length and number of weights according to user requirement. However, mitigation of MAI (multi access interference) is not done in the conventional MWML-OOC optical CDMA. Therefore users who demand high QoS cannot achieve bit error rate (BER) performance less than or equal to 10-12 due to the effect of the MAI. Moreover, general error correcting codes require the addition of the redundancy bits or an increase in number of weights, where the redundancy bits cause the decrease at the transmission rate, and the increase in the number of weights causes a decrease in the number of codes. In this paper, we apply SOC (super-orthogonal code) which can correct errors without adding redundant bits as well as increasing in number of weight for MWML-OOC optical CDMA to mitigate MAI. Since our scheme can reduce the number of optical pulses, the proposed scheme can mitigate the effect of MAI compared with the conventional scheme. We show that the proposed scheme can improve the BER performance in comparison with the conventional scheme.