Optical network employing erbium-doped fiber amplifiers

• US 7,092,636 B2
• Filed: 05/28/2002
• Issued: 08/15/2006
• Est. Priority Date: 03/29/1996
• Status: Expired due to Fees

• Current Assignee: Seafort International Trading, S.r.l.
• Original Assignee: Dominion Lasercom, Inc., A Nevada Corporation
• Inventors: Panak, David L., Doucet, Mark A.
• Primary Examiner(s): Phan, Hanh
• Application Number:
  US10/156,172
• Publication Number:
  US 20020141020A1
• Time in Patent Office: 1,540 Days
• Field of Search: 398/92, 398115-116, 398/118, 398/128, 398/130, 398/136, 398/157, 398/160, 398/117, 398/119, 398/120, 398/135, 359/341, 359/337, 359/341.1, 359/341.3
• US Class Current: 398/120
• CPC Class Codes: G02B 6/4405 with longitudinally spaced waveguide clamping G02B6/4429, G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: G02B 6/4411 Matrix structure
• CPC Class Codes: G02B 6/4416 Heterogeneous cables
• CPC Class Codes: G02B 6/4459 Ducts; Conduits; Hollow tubes for air blown fibres
• CPC Class Codes: H01B 11/22 Cables including at least one electrical conductor together with optical fibres
• CPC Class Codes: H04B 10/1121 One-way transmission
• CPC Class Codes: H04B 10/1125 using a single common optical path
• CPC Class Codes: H04B 10/1127 using two distinct parallel optical paths
• CPC Class Codes: H04L 5/16 Half-duplex systems; Simplex/duplex switching; Transmission of break signals non-automatically inverting the direction of transmission

Abstract

A point-to-multipoint bi-directional wide area telecommunications network employing atmospheric optical communication. The network comprises a primary transceiver unit, a plurality of subscriber transceiver units and an optical router. The primary transceiver unit may send data destined for the subscriber transceiver units through the optical router, and the subscriber transceiver units may send data destined for the primary transceiver unit through the optical router. The primary transceiver unit and optical router communicate by means of light beams which are transmitted through the atmosphere. Similarly, the optical router and the subscriber transceiver units communicate by means of light beams which are transmitted through the atmosphere.

Claims

1. A terrestrial optical communication network comprising:

a plurality of fiber optic links and free-space links between which optical signals are optically coupled by erbium doped fiber amplifiers (EDFAs), wherein a power gain of at least one of the EDFAs is operable to be controlled in response to one or more factors;

at least one optical router connected to a plurality of links, wherein the optical router includes one or more EDFAs to optically couple the optical signals from one of the links connected to the optical router to another one of the links connected to the optical router.

2. A terrestrial optical communication network as defined in claim 1 wherein the one or more factors comprise weather conditions.

3. A terrestrial optical communication network as defined in claim 1 wherein the one or more factors comprise an optical signal received over one of the free-space links.

4. A terrestrial optical communication network as defined in claim 1, further comprising a control system for controlling the power gain of at least one of the EDFAs.

5. A terrestrial optical communication network as defined in claim 4, wherein the control system is an active optics control system.

6. A terrestrial optical communication network as defined in claim 1, wherein the EDFAs include a transmitting EDFA, wherein the transmitting EDFA amplifies one of the optical signals before its transmission over at least one of the free-space links, and further comprising a controller connected to the transmitting EDFA to control the optical power gain of the transmitting EDFA to adjust the optical power of the optical signal transmitted over the one free-space link.

7. A terrestrial optical communication network as defined in claim 1, wherein the EDFAs include a receiving EDFA, wherein the receiving EDFA amplifies one of the optical signals after its reception over at least one of the free-space links, and further comprising a controller connected to the receiving EDFA to control the optical power gain of the receiving EDFA to adjust the optical power of the optical signal delivered by the receiving EDFA.

8. A terrestrial optical communication network comprising;

a plurality of network elements coupled together by a plurality of fiber optic links and free-space links, wherein the terrestrial optical communication network further comprises one or more erbium doped fiber amplifiers (EDFA) in one or more of the network elements for amplifying light beams in the network in order to achieve appropriate signal power levels of the light beams within the network;

at least one optical router connected to a plurality of links, wherein the optical router includes one or more EDFAs to optically couple the optical signals from one of the links connected to the optical router to another one of the links connected to the optical router.

9. A terrestrial optical communication network as defined in claim 8, wherein the one or more EDFAs are operable to provide adjustable light beam power control according to one or more factors.

10. A terrestrial optical communication network as defined in claim 9 wherein the one or more factors comprise weather conditions.

11. A terrestrial optical communication network as defined in claim 9 wherein the one or more factors comprise an optical signal received over one of the free-space links.

12. A terrestrial optical communication network as defined in claim 8, further comprising a control system for controlling the power gain of at least one of the EDFAs.

13. A terrestrial optical communication network as defined in claim 8, wherein the EDFAs include a transmitting EDFA, wherein the transmitting EDFA amplifies one of the optical signals before its transmission over at least one of the free-space links, and further comprising a controller connected to the transmitting EDFA to control the optical power gain of the transmitting EDFA to adjust the optical power of the optical signal transmitted over the one free-space link.

14. A terrestrial optical communication network as defined in claim 8, wherein the EDFAs include a receiving EDFA, wherein the receiving EDFA amplifies one of the optical signals after its reception over at least one of the free-space links, and further comprising a controller connected to the receiving EDFA to control the optical power gain of the receiving EDFA to adjust the optical power of the optical signal delivered by the receiving EDFA.

15. A terrestrial optical communication network comprising:

a plurality of network elements;

a plurality of fiber optic links and free-space links for coupling the plurality of network elements through transfer of light beams; and

one or more erbium doped fiber amplifiers (EDFA) for amplifying the light beams in the network in order to achieve appropriate signal power levels of the light beams within the network;

wherein the plurality of network elements comprises at least one optical router connected to a plurality of the links, wherein the optical router includes one or more EDFAs to optically couple the optical signals from one of the links connected to the optical router to another one of the links connected to the optical router.