Optical receiving device and transmission device

Patent metadata

Field	Value
Publication number	US-9716556-B2
Application number	US-201414494900-A
Country	US
Kind code	B2
Filing date	Sep 24, 2014
Priority date	Oct 31, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

An optical receiving device includes: a conversion device that converts an input burst optical signal into a positive phase electrical signal and a negative phase electrical signal; an amplification device that amplifies the positive phase electrical signal and the negative phase electrical signal; a first output terminal that outputs the positive phase electrical signal; a second output terminal that outputs the negative electrical signal; a first transmission line that couples the amplification device with the first output terminal and transmits the positive phase electrical signal; a second transmission line that couples the amplification device with the second output terminal and transmits the negative phase electrical signal; and a control device that reduces a potential difference between the first transmission line and the second transmission line in a no-signal period that is provided between burst optical signals.

First claim

What is claimed is:

1. An optical receiving device comprising:
a conversion device that converts an input burst optical signal into a positive phase electrical signal and a negative phase electrical signal;
an amplification device that amplifies the positive phase electrical signal and the negative phase electrical signal;
a first output terminal that outputs the positive phase electrical signal from the amplification device to a signal processing device via a first capacitor;
a second output terminal that outputs the negative phase electrical signal from the amplification device to the signal processing device via a second capacitor, the signal processing device processing the positive phase electrical signal and the negative phase electrical signal;
a first transmission line that couples the amplification device with the first capacitor and transmits the positive phase electrical signal;
a second transmission line that couples the amplification device with the second capacitor and transmits the negative phase electrical signal; and
a control device that reduces a potential difference between the first transmission line and the second transmission line in a no-signal period that is provided between burst optical signals.

2. The optical receiving device as claimed in claim 1 , wherein:
the conversion device outputs the positive phase electrical signal through a first output terminal, and outputs the negative phase electrical signal through a second output terminal,
the first transmission line couples the amplification device with the first output terminal via the first capacitor;
the second transmission line couples the amplification device with the second output terminal via the second capacitor;
the control device reduces the potential difference between a portion of the first transmission line between the amplification device and the first capacitor and a portion of the second transmission line between the amplification device and the second capacitor in the no-signal period.

3. The optical receiving device as claimed in claim 1 further comprising a detection device that detects a current output from the conversion device when the burst optical signal is input and outputs a detection signal to the control device,
wherein the control device reduces the potential difference between the first transmission line and the second transmission line based on the detection signal.

4. The optical receiving device as claimed in claim 1 , wherein the control device shorts between the first transmission line and the second transmission line in the no-signal period and opens between the first transmission line and the second transmission line in a period in which the burst optical signal is being input.

5. The optical receiving device as claimed in claim 1 , wherein the control device applies a bias voltage to the first transmission line and the second transmission line so that the potential difference between the first transmission line and the second transmission line is reduced in the no-signal period, and stops applying the bias voltage to the first transmission line and the second transmission line during the period in which the burst optical signal is being input.

6. A transmission device comprising:
a conversion device that converts an input burst optical signal into a positive phase electrical signal and a negative phase electrical signal;
an amplification device that amplifies the positive phase electrical signal and the negative phase electrical signal;
a signal processing device that processes the positive phase electrical signal and the negative phase electrical signal that are amplified by the amplification device;
a first transmission line that couples the amplification device with the signal processing device via a first capacitor and transmits the positive phase electrical signal;
a second transmission line that couples the amplification device with the signal processing device via a second capacitor and transmits the negative phase electrical signal; and
a control device that reduces a potential difference between a portion of the first transmission line between the amplification device and the first capacitor and a portion of the second transmission line between the amplification device and the second capacitor in a no-signal period that is provided between burst optical signals.

7. The transmission device as claimed in claim 6 further comprising a detection device that detects a current output from the conversion device when the burst optical signal is input and outputs a detection signal to the control device,
wherein the control device reduces the potential difference between the portion of the first transmission line between the amplification device and the first capacitor and the portion of the second transmission line between the amplification device and the second capacitor based on the detection signal.

8. The transmission device as claimed in claim 6 , wherein the control device shorts between the portion of the first transmission line between the amplification device and the first capacitor and the portion of the second transmission line between the amplification device and the second capacitor in the no-signal period, and opens between the portions in a period in which the burst optical signal is being input.

9. The transmission device as claimed in claim 6 , wherein the control device applies a bias voltage to the portion of the first transmission line between the amplification device and the first capacitor and the portion of the second transmission line between the amplification device and the second capacitor so that the potential difference between the portions is reduced in the no-signal period, and stops applying the bias voltage to the portions in a period in which the burst optical signal is being input.

10. An optical receiving device comprising:
a conversion device that converts an input burst optical signal into a positive phase electrical signal and a negative phase electrical signal;
an amplification device that amplifies the positive phase electrical signal and the negative phase electrical signal;
a first output terminal that outputs the positive phase electrical signal;
a second output terminal that outputs the negative electrical signal;
a first transmission line that couples the amplification device with the first output terminal and transmits the positive phase electrical signal;
a second transmission line that couples the amplification device with the second output terminal and transmits the negative phase electrical signal;
a signal detection device that detects inputting of the input burst optical signal based on voltage levels of the positive phase electrical signal and the negative phase electrical signal; and
a control device that connects together the first transmission line and the second transmission line, and thereby short circuits between the first transmission line and the second transmission line, in a no-signal period between burst optical signals, and disconnects the first transmission line and the second transmission line from each other in a period in which the burst optical signal is being input according to the detection of the signal detection device.

Assignees

• Fujitsu Optical Components Ltd

Inventors

• Sakuramoto Shinichi

Classifications

• H04B10/272

  Star-type networks {or tree-type networks} · CPC title

• H04B10/6933 Primary

  Offset control of the differential preamplifier · CPC title