Patent US2657985A successfully refreshed from Google Patents.
EP0449475A2
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Telemetry for optical fiber amplifier repeater
Assignee: AT&T Inc
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Filing: 1991-03-18
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Granted: —
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Expires: 2011-03-18
Abstract
Abstract In this invention telemetry information is transmitted in an optical fiber communication system by providing an amplifier pump (74) with excess power beyond that necessary to pump the amplifier (51). The excess power is not used to pump the amplifier but is rather used to transmit the telemetry information. In a specific embodiment, an optical communication system including a doped optical fiber amplifier such as, for example, an erbium doped amplifier, is provided with an amplifier pump which operates at approximately 1.48µm. The amplifier pump is provided with excess power so as to transmit telemetry information. In a specific embodiment, the telemetry signal can be detected with a low cost photodetector (54) at a subsequent station.
Inventors
- 👤 M.T. Fatehi
- 👤 Nils Anders Olsson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 09:11
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/26; G01D5/28; H; H04; H04B; H04B10/00; H04B10/29; H04B10/291; H04B10/293; H04B10/2931; H04B10/07; H04B10/075; H04B10/077; H04B10/0777; H04B10/2912; H04B2210/00; H04B2210/07; H04B2210/074; H04B2210/078
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
32 words
A telemetry system for an optical fiber transmission system comprising an optically pumped optical amplifier, and modulating means coupled to modulate the pump signal to said optical amplifier to carry telemetry signals.
Claim 2
Dependent Claim
28 words
The telemetry system of claim 1 wherein said optically pumped optical amplifier comprises a pump having a signal which is greater than that required by said optical amplifier.
Claim 3
Dependent Claim
50 words
The telemetry system of claim 2 wherein said modulating means comprises a modulator coupled to modulate the pump signal, an oscillator coupled to said modulator for providing a carrier signal for modulating the pump signal and, means for coupling a telemetry signal to said modulator for modulating the carrier signal.
Claim 4
Dependent Claim
18 words
The telemetry system of claim 3 wherein said modulator amplitude modulates said carrier signal with said telemetry signal.
Claim 5
Dependent Claim
18 words
The telemetry system of claim 3 wherein said modulator frequency modulates said carrier signal with said telemetry signal.
Claim 6
Dependent Claim
18 words
The telemetry system of claim 3 wherein said modulator phase-shift-key modulates said carrier signal with said telemetry signal.
Claim 7
Dependent Claim
20 words
The telemetry system of claim 3 wherein said modulator amplitude shift key modulates said carrier signal with said telemetry signal.
Claim 8
Dependent Claim
20 words
The telemetry system of claim 3 wherein said modulator frequency shift key modulates said carrier signal with said telemetry signal.
Claim 9
Dependent Claim
49 words
The telemetry system of claim 3 comprising an optical fiber coupled to said optical amplifier for carrying optical signals, a coupler coupled to said optical fiber at a location remote from said optical amplifier for separating the received pump signal from a data signal amplified by said optical amplifier.
Claim 10
Dependent Claim
27 words
The telemetry system of claim 9 comprising demodulator means coupled to receive the pump signal from said coupler to separate the telemetry signal from said carrier signal.
Claim 11
Dependent Claim
24 words
The telemetry system of claim 10 wherein the frequency of said carrier signal lies between the range of 2KH z through 400MH z .
Claim 12
Dependent Claim
34 words
The telemetry system of claim 2 wherein the wavelength of the signal from the optical amplifier is substantially 1.55µm and the wavelength of the signal from the pump is at substantially 1.48µm or lower.
Claim 13
Dependent Claim
20 words
The telemetry system of claim 3 where the modulated carrier signal travels in the same direction (co-propagating) as the data.
Claim 14
Dependent Claim
23 words
The telemetry system of claim 3 where the modulated carrier signal travels in a direction opposite (counter-propagating) to the direction of the data.
Claim 15
Dependent Claim
34 words
The telemetry system of claim 3 wherein said oscillator generates a signal having a frequency of less than 2KH z to effect gain modulation of a data signal being amplified by said optical amplifier.
Claim 16
Dependent Claim
34 words
An optical amplifier comprising a doped optical fiber, a pump coupled to pump said doped optical fiber, means coupled to said pump for modulating the signal to the doped optical fiber from said pump.
References Cited (Backward Citations)
No citation records indexed.
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