PASSIVE OPTICAL NETWORK SYSTEM OF RING STRUCTURE BY USING BAND PASS FILTER

摘要

A passive optical network system of a ring structure by using a band pass filter is provided to connect one OLT(Optical Line Termination) with plural ONUs(Optical Network Units), thereby constructing an optical subscriber network at very low cost. Plural OLTs(200-1~200-4) are connected to a backbone network(100) one to one. FBG(Fiber Bragg Grating) filters(21-1~21-4) are located between each of the OLTs(200-1~200-4) and ODNs(Optical Distribution Nodes)(300-1~300-4), and pass specific wavelengths only. The ODNs(300-1~300-4) distribute signals of the OLTs(200-1~200-4) one to N. Subscriber-side ONUs are connected to the ODNs(300-1~300-4), respectively.