Optical level control apparatus and optical reception apparatus

Patent metadata

Field	Value
Publication number	US-10003406-B2
Application number	US-201414501499-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Oct 28, 2013
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

An optical level control apparatus includes an input port, an output port, an optical device to assume a state of outputting light inputted to the input port from the output port and a state of not outputting the light inputted to the input port from the output port; a detector to detect an intensity of the light inputted to the input port, and a control unit to detect an input of an optical burst signal to the input port on the basis of a result of detecting the intensity of the light and to control the optical device so that the signal, in which to eliminate a field extending up to an elapse of a period of first time equal to or shorter than laser ON time period of the signal from a head of the signal with its input being detected, is output from the output port.

First claim

What is claimed is:

1. An optical level control apparatus comprising:
an input port configured to receive input light, the light being amplified by an optical fiber amplifier;
an output port;
an optical device configured to assume a state of outputting light that was input to the input port from the output port and a state of not outputting the light that was input to the input port from the output port;
a detector configured to detect an intensity of the light input at the input port; and
a control unit configured to detect an input of an optical burst signal to the input port on the basis of a result of detecting the intensity of the light by the detector and to control the optical device so that the optical burst signal, in which a field extending up to an elapse of a first period of time equal to or shorter than a laser ON time period defined by a period of time from a head of the optical burst signal with its input being detected until starting modulation of the optical burst signal is eliminated, is output from the output port, the first period of time being for eliminating an optical surge overlapped with the optical burst signal,
wherein a reception device configured to receive the optical signal output from the output port notifies the control unit that input over-power occurs when the intensity of the received optical burst signal is stronger than a fixed intensity, the reception device being arranged outside the optical level control apparatus, and
the control unit adjusts the first period of time to a shortest period of time on the basis of whether or not input over-power occurs, wherein the shortest period of time is a period during which the reception device arranged outside the optical level control apparatus ceases notification of the input over-power, and wherein the shortest period of time is selected from among a plurality of periods of time that are selectable by the control unit,
wherein the reception device configured to receive the optical signal output from the output port notifies the control unit that a reception signal error occurs when the received optical burst signal is not converted into digital data, and
the control unit adjusts the first period of time to a longest period of time during which notification of the reception signal error from the reception device ceases among the plurality of periods of time selectable by the control unit on the basis of whether the notification of the occurrence of the reception signal error is given or not, the reception device being arranged outside the optical level control apparatus.

2. The optical level control apparatus according to claim 1 , wherein the control unit controls the optical device to distinguish a sender device of each optical burst signal input to the input port on the basis of information indicating timing when each of a plurality of sender devices transmits the optical burst signal, to manage and adjust the first period of time per distinguished sender device, and to output, from the output port, the optical burst signal in which the field extending up to the elapse of the first period of time being adjusted underway or having been adjusted from the head of the optical burst signal with its input being detected with respect to the sender device of the optical burst signal is eliminated.

3. The optical level control apparatus according to claim 1 , wherein the optical device is controlled in a first state of outputting the light input to the input port from the output port and in a second state of not outputting the light input to the input port from the output port, and
the control unit controls the optical device to operate in the first state when the first period of time elapses since detecting the input of the optical burst signal to the input port on the basis of the result of detecting the intensity of the light by the detector, and controls the optical device to operate in the second state when detecting completion of inputting the optical burst signal to the input port on the basis of the result of detecting the intensity of the light by the detector.

4. The optical level control apparatus according to claim 1 , further comprising a delay element configured to get the optical device to input a field extending from the head up to after the elapse of the first period of time in the optical burst signal input to the input port when the optical device starts operating in the first state under the control of the control unit.

5. An optical reception apparatus comprising:
a reception system configured to convert an optical burst signal into an electric signal; and
an optical level control system, the optical level control system comprising:
an input port configured to receive input light, the light being amplified by an optical fiber amplifier;
an optical device configured to assume a state of supplying light that was input to the input port to the reception system and a state of not supplying the light that was input to the input port to the reception system;
a detector configured to detect an intensity of the light that was input to the input port; and
a control unit configured to detect an input of the optical burst signal to the input port on the basis of a result of detecting the intensity of the light by the detector and to control the optical device so that the optical burst signal, in which a field extending up to an elapse of a first period of time equal to or shorter than a laser ON time period defined by a period of time from a head of the optical burst signal with its input being detected until starting modulation of the optical burst signal is eliminated, is supplied to the reception system, the first period of time being for eliminating an optical surge overlapped with the optical burst signal,
wherein the reception system notifies the control unit that input over-power occurs when the intensity of the received optical burst signal is stronger than a fixed intensity, the reception system being arranged outside the optical level control system, and
the control unit adjusts the first period of time to a shortest period of time on the basis of whether or not input over-power occurs, wherein the shortest period of time is a period during which the reception system arranged outside the optical level control system ceases notification of the input over-power, and wherein the shortest period of time is selected from among a plurality of periods of time that are selectable by the control unit,
wherein the reception system notifies the control unit that a reception signal error occurs when the received optical burst signal is not converted into digital data, and
the control unit adjusts the first period of time to a longest period of time during which notification of the reception signal error from the reception system ceases among the plurality of periods of time selectable by the control unit on the basis of whether the notification of the occurrence of the reception signal error is given or not, the reception system being arranged outside the optical level control apparatus.

6. The optical level control apparatus according to claim 1 , further comprising an optical fiber amplifier configured to amplify the light inputted to the input port and to supply the amplified light to the optical device.

Assignees

• Fujitsu Ltd

Inventors

• Yoshida Setsuo
• Harada Keisuke

Classifications

• H04B10/272

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• H04B10/2914

  using lumped semiconductor optical amplifiers [SOA] · CPC title

• H04B10/293 Primary

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