Patent ID: 7415205
Filing Date: 2008-08-19
Classification: H04J

Abstract:
1. A wavelength division multiplexed self-healing passive optical network using a wavelength injection method, the wavelength division multiplexed self-healing passive optical network comprising: a central office for coupling modulated multiplexing optical signals and broadband optical signals for upstream light source which are to be transmitted to a plurality of optical network units through a working main fiber and a protection main fiber, into one signal and transmitting the coupled signal; a remote node connected to the central office through the working main fiber and the protection main fiber, the remote node connected to the optical network units through working distribution fibers and protection distribution fibers, the remote node demultiplexing the modulated multiplexing optical signals and the broadband optical signals for upstream light source transmitted from the central office through the working main fiber and the protection main fiber, and the remote node transmitting the demultiplexed signals to the optical network units; and optical network units for receiving the modulated optical signals and the broadband optical signals for upstream light source, which are transmitted from the remote node and correspond to predetermined optical network units, optically demodulating the modulated optical signals, and modulating upstream optical signals by means of the demultiplexed broadband optical signals for upstream light source, wherein the central office comprises: a broadband light source for downstream light source for providing a plurality of downstream light sources with broadband optical signals for providing injection light; a first N×N multiplexer/demultiplexer for performing a 1 ×(n- the downstream light sources using a wavelength injection method for receiving the optical signals demultiplexed by the first N×N multiplexer/demultiplexer, and optically modulating the received optical signals for data transmission to the optical network units; a broadband light source for upstream light source for providing the optical network units with broadband optical signals for providing injection light for the upstream optical signal; a 2×2 optical coupler for coupling the modulated multiplexing optical signals and the broadband optical signals for upstream light source having been transmitted from the first N×N multiplexer/demultiplexer, and transmitting the coupled signal through the working main fiber and the protection main fiber; a first circulator for providing the first N×N multiplexer/demultiplexer with the broadband optical signals from the broadband light source for downstream light source, providing the 2×2 optical coupler with the modulated multiplexing optical signals from the first N×N multiplexer/demultiplexer, and determining an optical path; a second circulator for providing the 2×2 optical coupler with the broadband optical signals from the broadband light source for upstream light source, providing the first N×N multiplexer/demultiplexer with an upstream transmission signal from the remote node inputted from the 2×2 optical coupler, and determining an optical path; and the upstream optical receivers for receiving the upstream transmission signals from the remote node, which have been demultiplexed by the first N×N multiplexer/demultiplexer.