Hybrid communication system applying electric CDMA over optical WDM

The purpose of this work is to describe and demonstrate a new concept of a hybrid communication system, which consists of applying electrical CDMA to each data channel, on a system using optical WDM. Each user has a unique orthogonal CDMA code and modulates an electrical carrier (e.g. QPSK) prior to the data is used to directly modulate an optical carrier, using a laser. Therefore, it is possible to add several independent data channels in a physical link (optical fiber), over the same or different optical carriers, and recover the information associated to each of the channels. With this approach we can avoid the use of optical filters to separate the data channels at reception, making the system more flexible and robust.