Patent ID: 6335810
Filing Date: 2002-01-01
Classification: H04B,H04J

Abstract:
An optical ADM (add-drop multiplexing) apparatus responsive to a WDM (wavelength division-multiplexed) optical signal comprising first through n-th (n being an integer not less than 2) main signal components different in wavelength from one another and a single monitor/control signal component different in wavelength from each of said first through said n-th main signal components, wherein:said monitor/control signal component carries first through n-th monitor/control signals which represent origination apparatus identifiers of origination apparatuses of said first through said n-th main signal components and destination apparatus identifiers of destination apparatuses of said first through said n-th main signal components in correspondence to said first through said n-th main signal components; said optical ADM apparatus comprising: a divider for dividing said WDM optical signal into said first through said n-th main signal components and said monitor/control signal component; a monitor/control signal terminator coupled to said divider for terminating said monitor/control signal component to produce said first through said n-th monitor/control signals; a monitor/control signal processor connected to said monitor/control signal terminator for producing, when the destination apparatus identifier represented by one of said first through said n-th monitor/control signals is coincident with an identifier of said optical ADM apparatus, a specifying signal specifying, as a specified main signal component, one of said first through said n-th main signal components that corresponds to said one of the first through the n-th monitor/control signals, said monitor/control signal processor further producing said first through said n-th monitor/control signals with the origination apparatus identifier corresponding to said specified main signal component rewritten into the identifier of said optical ADM apparatus and with the destination apparatus identifier corresponding to said specified main signal component rewritten into a different apparatus identifier of a different apparatus which is different from said optical ADM apparatus; an ADM unit coupled to said divider and connected to said monitor/control signal processor for dropping, when receives said specifying signal from said monitor/control signal processor, said specified main signal component from said first through said n-th main signal components and for producing, when receives a new main signal component equal in wavelength to said specified main signal component, said first through said n-th main signal components with said new main signal component added as said specified main signal component; an ADM terminal station coupled to said ADM unit for receiving said specified main signal component from said ADM unit and for transmitting to said ADM unit said new main signal component equal in wavelength to said specified main signal component; a monitor/control signal component generator connected to said monitor/control signal processor for producing said monitor/control signal component which carries said first through said n-th monitor/control signals produced by said monitor/control signal processor; and an optical combiner coupled to said ADM unit and said monitor/control signal component generator for producing another WDM optical signal comprising said first through said n-th main signal components produced by said ADM unit and said monitor/control signal component produced by said monitor/control signal component generator.