Wavelength Division Multiplexing Transmission system and Remote Apparatus and Station Apparatus Used Therein

A remote apparatus in a wavelength division multiplexing transmission system in which a plurality of remote apparatuses are connected to a station apparatus and communication is performed among the remote apparatuses and the station apparatus using a given plurality of wavelengths, the remote apparatus comprising:

• a receiver which receives transmissions from the station apparatus of one or more wavelengths of the given plurality of wavelengths;
• a wavelength separating device which separates, according to a wavelength control signal, a wavelength from the given plurality of wavelengths;
• a signal output device which outputs a reception status signal indicating whether or not a separated wavelength is received from the wavelength separating device;
• and
• a wavelength control device which generates the wavelength control signal to the wavelength separating device and receives a reception status signal to determine whether a signal corresponding to the separated wavelength is being received, and,
• if not, sets the separated wavelength as the wavelength to be used in the remote apparatus and wherein the remote apparatus transmits a signal having said separated wavelength to said station apparatus,
• but if it is determined that a signal corresponding to the separated wavelength is received, then generating a new wavelength control signal to control the wavelength separating device to separate a different wavelength from the given plurality of wavelengths until the wavelength control device determines that no signal corresponding to the separated different wavelength is being received, wherein when no signal corresponding to the separated different wavelength is being received the remote apparatus causes the station apparatus to be updated to include the separated different wavelength to be transmitted by the station apparatus with the given plurality of wavelengths.

A method for setting a wavelength to be used by a remote apparatus in a wavelength division multiplexing transmission system in which a plurality of remote apparatuses are connected to a station apparatus and communication is performed among the remote apparatuses and the station apparatus using a given plurality of wavelengths, the method comprising:

• transmitting from the station apparatus one or more wavelengths of the given plurality of wavelengths to the plurality of remote apparatuses and the remote apparatus to be added to said wavelength division demultiplexing transmission system;
• separating a wavelength from one or more wavelengths of the given plurality of wavelengths transmitted by a transmitter of the station apparatus, said step of separating being preformed according to a wavelength control signal;
• outputting a reception status signal indicating whether or not the separated wavelength is received;
• and
• controlling generation of a wavelength control signal used in said separating step based on said reception status signal output in said outputting step, said controlling step
• determining whether a signal corresponding to the separated wavelength is being received, and, if not, setting the separated wavelength as the wavelength to be used in the remote apparatus,
• once a separated wavelength that is not received at said remote apparatus is determined in said controlling step, transmitting a signal having said separated wavelength from said remote apparatus to said station apparatus,
• but if it is determined that a signal corresponding to the separated wavelength is being received, then
• generating a new wavelength control signal to control the wavelength separating device at the remote apparatus to separate a different wavelength from the given plurality of wavelengths until it is determined that no signal corresponding to the separated wavelength is being received, and
• updating said one or more wavelengths of the given plurality of wavelengths transmitted from the station apparatus to the plurality of remote apparatuses to include the separated wavelength.