EP0168192A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Receiver for lightwave transmission system using homodyne detection
Assignee: AT&T Inc
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Filing: 1985-06-24
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Granted: —
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Expires: 2005-06-24
Abstract
Abstract A coherent electromagnetic wave transmission system includes an electromagnetic wave transmission medium (30) for propagating two orthogonally polarized coherent electromagnetic signals. When received the two polarized signals are separated into an information component (52) and a reference component (48) that is coherent with the information component. The reference component drives an amplifier (50) for producing an amplified reference component that is coherent with the information component. Mixing the coherent amplified reference component with the information component in a homodyne detector produces a baseband information signal (82).
Inventors
- 👤 Neal Salvatore Bergano
- 👤 Harry John Schulte, Jr.
- 👤 Richard Edward Wagner
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 05:04
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/25; H04B10/60; H04B10/61; H04B10/614; H04B10/63
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
98 words
A coherent electromagnetic wave transmission system for transmitting information through a transmission medium; CHARACTERIZED BY a transmitter arranged for transmitting into the transmission medium a beam including a reference carrier signal and an information modulated carrier signal which are coherent with each other; amplitude control means responsive to the beam transmitted through the transmission medium for applying a different amplification to a component of the reference carrier signal than to a component of the information modulated carrier signal; and combining means for mixing the amplified reference component with the coherent information component to produce a baseband information signal.
Claim 2
Dependent Claim
98 words
A coherent electromagnetic wave transmission system for transmitting information through a transmission medium; CHARACTERIZED BY a transmitter arranged for transmitting into the transmission medium a beam including a reference carrier signal and an information modulated carrier signal which are coherent with each other; amplitude control means responsive to the beam transmitted through the transmission medium for applying a different amplification to a component of the reference carrier signal than to a component of the information modulated carrier signal; and combining means for mixing the amplified reference component with the coherent information component to produce a baseband information signal.
Claim 3
Dependent Claim
74 words
The coherent electromagnetic wave transmission system according to claim 1 further CHARACTERIZED IN THAT a beam splitter is coupled to the transmission medium and is responsive to the electromagnetic wave signals for separating those signals into the information modulated carrier and the reference carrier signal, and said amplitude control means comprises an optical amplifier responsive to the reference carrier signal for producing an amplified reference component that is coherent with the information modulated carrier.
Claim 4
Dependent Claim
41 words
The coherent electromagnetic wave transmission system according to claim 2, further CHARACTERIZED BY a polarization controller responsive to states of polarization of the reference carrier signals and the information modulated carrier for maintaining a fixed relationship between the states of polarization.
Claim 5
Dependent Claim
55 words
The coherent electromagnetic wave transmission system according to claim 3, further CHARACTERIZED BY phase control signal generating means, responsive to the baseband information signal, for producing a phase control signal, and phase control means responsive to the phase control signal for controlling the relative phase between the reference carrier signal and the information modulated carrier.
References Cited (Backward Citations)
No citation records indexed.
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