Time/wavelength-division multiplexed passive optical network (TWPON)

摘要

The present invention discloses a time/wavelength-division multiplexed passive optical network (TWPON), which has an optical splitter (21) and a waveguide grating router (WGR) (22) disposed at a remote node (RN) (20). The optical splitter (21) and the WGR (22) can be connected in a cascade or in a parallel such that the present invention can use less number of wavelengths to increase transmission capacity or increase the number of users. A channel fault monitoring (CFM) module provided at an optical line terminal (OLT) is utilized to locate fiber breaks among distribution fibers. The TWPON of the present invention can provide TDM-PON, WDM-PON, and Hybrid PON co-existing platform with less wavelengths channel fault monitoring mechanism.

主权项

1. A time/wavelength-division multiplexed passive optical network (TWPON), which is divided into an optical line terminal, a remote node, and a plurality of optical network units in structure, characterized in that the TWPON comprises:
a first-stage optical splitter for splitting a received time-division optical signal to form multi-way time-division optical signals; a multiple-input and multiple-output waveguide grating router, coupled to outputs of the optical splitter, having a plurality of input ports and a plurality of output ports, wherein the input ports respectively receives the multi-way time-division optical signals, the output ports respectively outputs the multi-way time-division optical signals, and each output port outputs a single time-division optical signal; a plurality of second-stage optical splitters respectively coupled to the output ports of the multiple-input and multiple-output waveguide grating router, wherein each second-stage optical splitter is utilized to split the single time-division optical signal outputted from each output port of the multiple-input and multiple-output waveguide grating router again, and the time-division optical signals split and obtained from the second-stage optical splitters are respectively transmitted to the optical network units; and a wavelength band filter disposed at a front end of the first-stage optical splitter, wherein the wavelength band filter is utilized to select a mixed optical signal, which comprises a set of wavelengths that are different from each other, from the optical line terminal, and make the mixed optical signal entering one of the input ports of the multiple-input and multiple-output waveguide grating router, the output ports of the multiple-input and multiple-output waveguide grating router respectively output wavelength components of the mixed optical signal to the respective second-stage optical splitters, and each second-stage optical splitter splits the received wavelength component, wherein at least two optical signals having the same wavelength component received by optical network units are coded and transmitted with a time-division manner.