Multicast Network with MMI-Based Optical Switches on Active Splitter/Active Combiner Structure

Multicast communications have become more and more important recently, especially in their applications in multimedia communication, quality of service (QoS), video conferencing, and distance education. In a point-to-point (PTP) optical communication system, how to provide multicast services is an essential issue. There are some advantages of active splitter/active combiner (AS/AC) networks, such as strictly nonblocking, simpler routing algorithm, lower system-insertion-loss, zero differential loss, and better signal-to-noise characteristics. The active multimode interference (MMI) coupler can provide splitting/combining operations with low loss and good balancing. It has been demonstrated that the AS/AC network constructed by active MMI switching devices can implement the multicast and PTP communications simultaneously. In this study, we offer two multicast algorithms, parallel multicast, and tunable multicast, on AS/AC network. The parallel multicast algorithm is suitable when there are multi requests arriving at the same time. The tunable multicast algorithm is suitable for balancing the output signals´ power.