Abstract: Disclosed herein is an Erbium-Doped Fiber Amplifier (EDFA) used in a WDM (Wavelength Division Multiplexing) transmission system. In accordance with the present invention, a variation of the intensity of the output optical signal in the optical fiber amplifier, which results from an gain imbalance due to different wavelength distribution caused by the gain inhomogeneity characteristics, can be prevented by examining the laser diode sensitive to the gain inhomogeneity characteristics in the erbium-doped optical fiber amplifier, constructing the filter having spectrum characteristics capable of suppressing the gain imbalance of the optical signal outputted from the optical fiber amplifier, and driving the sensitive laser diode using the electrical signal obtained by branching some of the input optical signal and passing the branched optical signal through the filter and driving other laser diodes with a constant voltage value.

Abstract: Disclosed herein is an Erbium-Doped Fiber Amplifier (EDFA) used in a WDM (Wavelength Division Multiplexing) transmission system. In accordance with the present invention, a variation of the intensity of the output optical signal in the optical fiber amplifier, which results from an gain imbalance due to different wavelength distribution caused by the gain inhomogeneity characteristics, can be prevented by examining the laser diode sensitive to the gain inhomogeneity characteristics in the erbium-doped optical fiber amplifier, constructing the filter having spectrum characteristics capable of suppressing the gain imbalance of the optical signal outputted from the optical fiber amplifier, and driving the sensitive laser diode using the electrical signal obtained by branching some of the input optical signal and passing the branched optical signal through the filter and driving other laser diodes with a constant voltage value.

Abstract: An optical packet header processing apparatus for processing a header of an optical packet expressing an address of a destination node to control a switching operation of an optical packet switch. The optical packet header processing apparatus comprises a beam splitter for splitting the optical packet header into a predetermined number of optical packet header elements, and a plurality of time interval detectors. Each of the time interval detectors receives a corresponding one of the optical packet header elements from the beam splitter and outputs a detect optical pulse if a pair of optical pulses having a predetermined time interval therebetween are present in the received optical packet header element. A plurality of optical pulse detectors are adapted to convert the detect optical pulses from the time interval detectors into electrical signals and transfer the converted electrical signals to the optical packet switch, respectively.

Abstract: The present invention is to provide an automatic gain-controlled optical fiber amplifier, comprising: a first optical branch for branching a portion of an optical signal inputted into the optical fiber amplifier; a second optical branch for branching a portion of an optical signal outputted from the optical fiber amplifier; an optical distributor for receiving the optical signal of an input side branched partially by the first optical branch and for outputting it separately; a first wavelength selector for receiving the optical signal of a one side distributed by the optical distributor and for selecting a predetermined wavelength optical signal; a second wavelength selector for receiving the optical signal of an output side branched partially by the second optical branch and for selecting the predetermined wavelength optical signal; a signal processor for receiving the optical signal of a second side distributed by the optical distributor and the predetermined wavelength optical signal selected by the first

Abstract: The present invention is to provide an automatic gain-controlled optical fiber amplifier, comprising: a first optical branch for branching a portion of an optical signal inputted into the optical fiber amplifier; a second optical branch for branching a portion of an optical signal outputted from the optical fiber amplifier; a optical distributor for receiving the optical signal of an input side branched partially by the first optical branch and for outputting separately it; a first wavelength selector for receiving the optical signal of an one side distributed by the optical distributor and for selecting a predetermined wavelength optical signal; a second wavelength selector for receiving the optical signal of an output side branched partially by the second optical branch and for selecting the predetermined wavelength optical signal; a signal processor for receiving the optical signal of a second side distributed by the optical distributor and the predetermined wavelength optical signal selected by the first