Simulation of MQC code of SAC/Optical CDMA and WDM hybrid overlay system

A hybrid WDM and SAC/Optical CDMA System is proposed to enhance the data network security and to exploit the capacity of an optical system. Code pulses of SAC/Optical CDMA are overlaid onto a multichannel WDM system. Modified Quadratic Congruence (MQC) code is as the signature address code for SAC/Optical CDMA. In general, OCDMA improves service availability for data of a network. With the use of WDM channels in a hybrid scheme, an eavesdropper faces another challenge for intercepting and decoding the coded signal. The interference that is the main factor limits the performance of the proposed system. So that, the notch filters and APD photo detectors instead of PIN photo detectors are used in order to improve the SAC/OCDMA performance. A simulation is presented as a demonstration of the concept.