A novel access and control system in a WDM passive star-coupled network for optical backhaul

A passive star-coupled (PSC) optical wavelength division multiplexing (WDM) network is considered a promising candidate for optical backhaul particularly in densely populated urban areas. In this paper, we present the access and control system design for wireless backhaul transmission over a PSC wavelength division multiple access (WDMA) network. We employ an in-band control-signal technique, providing dedicated control slot access, and the length of the control slot is minimized and unconstrained by the length of a data slot, aiming at offering thorough control information and maximizing the system performance. A packet-by-packet, reservation-based, and frame-basis medium access control (MAC) scheme is presented. The MAC scheme ensures round-robin scheduling to flexibly transmit data packets within a data frame by simply adopting two initial variables. The simulation results show that the network achieves exceptionally high system performance when each node is equipped with only one tunable transmitter and one fixed-tuned receiver for uniform destination traffic scenarios. In a client/server traffic scenario, only the server node (which receives an additional proportion of the entire network traffic) is upgraded by replacing the fixed-tuned receiver with a fast tunable receiver; thus, exceptionally high delay-throughput performance is maintained, and the most cost-effective solutions are proposed.