Optical ring network

Patent metadata

Field	Value
Publication number	US-10044462-B2
Application number	US-201415021595-A
Country	US
Kind code	B2
Filing date	Aug 29, 2014
Priority date	Sep 24, 2013
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

An exemplary apparatus is provided for an optical node of an optical ring network. The optical node comprises a main branch with a wavelength blocker configured to block at least one wavelength of signals targeted to a particular node and to permit the signals received on the other wavelength channels pass, a reception unit tuned to the at least one wavelength dedicated to signals targeted to the particular node, a first optical coupler configured to transmit the signals received from a previous node of the optical ring network both to the main branch and to the reception unit, a transmission unit configured to transmit signals to a wavelength channel according to their targeted node, and a second optical coupler configured to receive the signals received from the main branch and from the transmission unit and to transmit the received signals toward a next node of the optical ring network.

First claim

The invention claimed is:

1. An optical node of an optical ring network comprising links configured to transmit a plurality of multiplexed wavelength channels, the optical node comprising:
a wavelength blocker configured to block at least one wavelength channel of the plurality of multiplexed wavelength channels that has signals targeted to the optical node and to permit other wavelength channels to pass, wherein the wavelength blocker comprises at least one Bragg grating linked directly to an isolator, the direct link being only at an output of the isolator;
a reception unit tuned to the at least one wavelength channel;
a first optical coupler configured to transmit the plurality of multiplexed wavelength channels received from a previous node of the optical ring network to the reception unit and to the wavelength blocker, wherein the first optical coupler is linked directly to an input of the isolator;
a transmission unit configured to transmit signals to at least one of the other wavelength channels; and
a second optical coupler configured to receive signals from an output of the at least one Bragg grating and from the transmission unit, and to transmit the received signals toward a next node of the optical ring network.

2. The optical node in accordance with claim 1 , wherein the reception unit comprises at least one non-coherent receiver.

3. The optical node in accordance with claim 1 , wherein the transmission unit comprises at least one fast tunable laser.

4. The optical node in accordance with claim 1 , wherein the transmission unit and the reception unit are combined in a transceiver.

5. The optical node in accordance with claim 1 , wherein the transmission unit and the reception unit are remote from optical components of the optical node, and wherein the optical node comprises a first optical circulator located next to the optical components and connected to the first optical coupler and the second optical coupler and a second optical circulator connected to the transmission unit and the reception unit, the first optical circulator and the second optical circulator being linked by an optical link, the first optical circulator being configured to transmit the signals received from the first optical coupler to the second optical circulator and to transmit the signals received from the second optical circulator to the second optical coupler, the second optical circulator being configured to transmit the signals received from the first optical circulator to the reception unit and to transmit the signals received from the transmission unit to the first optical circulator.

6. The optical node in accordance with claim 5 , further comprising a base station remote from the optical components, wherein the base station comprises the reception unit and the transmission unit.

7. The optical ring network comprising a plurality of nodes in accordance with claim 1 , the plurality of nodes being linked by optical links, the optical links being configured to transmit a plurality of multiplexed wavelength channels.

8. The optical ring network in accordance with claim 7 , wherein the plurality of nodes comprises base stations of a cellular network, the base stations being neighboring base stations, and wherein the optical ring network comprises an additional node linked to a backbone network.

9. The optical ring network in accordance with claim 8 , wherein the additional node comprises:
at least one reception unit tuned to the at least one wavelength of the signals targeted to the backbone network;
at least one transmission unit to transmit the signals received from the backbone network to the other nodes of the optical ring network;
a demultiplexer configured to demultiplex the signals received from a previous node of the optical ring network and to transmit the at least one wavelength channel of the signals targeted to the backbone network to the at least one reception unit; and
a multiplexer configured to multiplex the signals received from the at least one transmission unit and from the demultiplexer and to transmit the multiplexed signals to a next node of the optical ring network.

10. The optical ring network in accordance with claim 8 , wherein the base stations are remote from optical components of the optical node.

11. The optical node in accordance with claim 1 , wherein the reception unit is tuned by a filter located in front of the reception unit, the filter being configured for filtering all the wavelength channels except the at least one wavelength channel.

12. A method for an optical node of an optical ring network comprising links configured to transmit a plurality of multiplexed wavelength channels, comprising:
receiving the plurality of multiplexed wavelength channels from a previous node of the optical ring network at a first optical coupler configured to transmit the plurality of multiplexed wavelength channels to a reception unit and a wavelength blocker, wherein the wavelength blocker comprises at least one Bragg grating linked directly to an isolator, the direct link being only at an output of the isolator, and wherein an output of the at least one Bragg grating is linked to a second optical coupler, and wherein the first optical coupler is linked directly to an input of the isolator, and wherein the reception unit is tuned to at least one wavelength channel of the plurality of multiplexed wavelength channels;
blocking the at least one wavelength channel of the plurality of multiplexed wavelength channels that has signals targeted to the optical node and permitting signals of other wavelength channels to pass; and
transmitting the signals of the other wavelength channels toward a next node of the optical ring network.

13. The optical node in accordance with claim 1 , wherein the reception unit is tuned by a filter integrated within the reception unit with a thin film technology.

14. The optical node in accordance with claim 1 , wherein a first output of the first optical coupler is linked to the reception unit and a second output of the first optical coupler is linked to the wavelength blocker.

15. The optical node in accordance with claim 1 , wherein the received signals are transmitted directly from the second optical coupler toward the next node of the optical ring network.

16. The optical node in accordance with claim 1 , wherein the optical ring network has a size of up to 50 kilometers.

Assignees

• Alcatel Lucent

Inventors

• De Valicourt Guilhem
• Pointurier Yvan

Classifications

• H04B10/25

  Arrangements specific to fibre transmission · CPC title

• H04B10/50

  Transmitters · CPC title

• H04B10/40

  Transceivers · CPC title

• H04B10/60

  Receivers · CPC title

• H04J14/0205

  Select and combine arrangements, e.g. with an optical combiner at the output after adding or dropping · CPC title