Patent ID: 7174102

Claim:
A bi-directional wavelength division multiplexing self-healing passive optical network comprising: a central office for dividing powers of generated and multiplexed downstream optical signals in a known ratio and transmitting the divided powers to both a first and a second main fibers; a downstream transmitter, coupled to the central office, for generating a plurality of downstream optical signals; a first wavelength division multiplexer, coupled to the central office, for wavelength division multiplexing the downstream optical signals to generate the multiplexed downstream optical signals; a first optical distributor, coupled to the central office, for dividing power of the multiplexed downstream optical signals to transmit the divided powers to the first and the second main fiber; a monitor, coupled to the central office, for generating a monitoring optical signal that is output to a first wavelength division multiplexer, and for recognizing whether abnormality occurs at the first and a second main fiber from a state of a return optical signal inputted from the first wavelength division multiplexer; a remote node connected to the central office through the first and the second main fiber, for transmitting multiple pairs of the downstream optical signals, which are obtained by demultiplexing one inputted pair of the multiplexed downstream optical signals according to wavelengths, to corresponding pairs of distribution fibers; and a plurality of optical network units connected to the remote node through the multiple pairs of distribution fibers, each of the optical network units being selectively connected to one corresponding pair of the distribution fibers by a switch, for receiving a corresponding downstream optical signal from the selected distribution fiber.