Optical transmission system and method using wavelength division multiplex
First Claim
1. A system for transmitting, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned, the system comprising:
- an optical transmission terminal station for transmitting the wavelength-multiplex signals to the optical transmission path;
an optical reception terminal station for receiving the wavelength-multiplex signals from the optical transmission path; and
at least one of Add/Drop-Multiplexer nodes each including at least a demultiplexer unit for demultiplexing a plurality of channels to a channel in accordance with a given wavelength and a multiplexer unit for multiplexing a plurality of channels in accordance with a given wavelength;
wherein optical pulses having pulse waveforms with an equal full-width at half-maximum are applied to the optical signals.
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Accused Products
Abstract
A system for transmitting, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned, the system comprising an optical transmission terminal station for transmitting the wavelength-multiplex signals to the optical transmission path, an optical reception terminal station for receiving the wavelength-multiplex signals from the optical transmission path, and at least one of ADD/Drop-Multiplexer nodes each including at least a demultiplexer unit for demultiplexing a plurality of channels to a channel in accordance with a given wavelength and a multiplexer unit for multiplexing a plurality of channels in accordance with a given wavelength, wherein optical pulses having pulse waveforms with an equal full-width at half-maximum are applied to the optical signals.
30 Citations
16 Claims
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1. A system for transmitting, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned, the system comprising:
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an optical transmission terminal station for transmitting the wavelength-multiplex signals to the optical transmission path; an optical reception terminal station for receiving the wavelength-multiplex signals from the optical transmission path; and at least one of Add/Drop-Multiplexer nodes each including at least a demultiplexer unit for demultiplexing a plurality of channels to a channel in accordance with a given wavelength and a multiplexer unit for multiplexing a plurality of channels in accordance with a given wavelength; wherein optical pulses having pulse waveforms with an equal full-width at half-maximum are applied to the optical signals. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method for transmitting and receiving, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned,
wherein when a plurality of channels in accordance with a given wavelength on the optical transmission path is demultiplexed and a plurality of channels in accordance with a given wavelength is multiplexed, optical pulses having pulse waveforms with an equal full-width at half-maximum are applied to the optical signals.
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13. A method for transmitting and receiving, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned,
wherein when a plurality of channels in accordance with a given wavelength on the optical transmission path is demultiplexed and a plurality of channels in accordance with a given wavelength is multiplexed, and when the wavelength-multiplex optical signal transmitted over the optical transmission path is amplified by an erbium-doped optical fiber amplifier, a signal intensity P (unit=W) of a peak in the outputs of the optical transmission terminal station and the erbium-doped optical fiber amplifier satisfies the condition of P< - Ps (unit=W), when Ps=(0.776λ
3 Aeff D)/(π
2 n2 cto2),wherein λ
(unit=m) is a wavelength, Aeff (unit=m2) is an effective core area of the optical fiber of the optical transmission path, D (unit=s/m/m) is a chromatic dispersive value of the optical fiber, n2 (unit=m2 /n) is a non-linear refractive index of the optical fiber, c (unit=m/s) is a velocity of light, and to (unit=S) is a full-width at half-maximum, andoptical pulses having pulse waveforms with an equal full-width at half-maximum are applied to the optical signals.
- Ps (unit=W), when Ps=(0.776λ
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14. A method for transmitting and receiving, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned,
wherein when the wavelength-multiplex signals transmitted over the optical transmission path is multiplexed/demultiplexed by a multiplexer/demultiplexer and the multiplexed/demultiplexed optical signal is amplified by an erbium-doped fiber amplifier, a formula, fsig-fADM≧ - Δ
B/2, is satisfied,wherein fsig (unit=Hz) is an optical frequency of a predetermined optical signal for a predetermined channel of the multiplexer and demultiplexer, fADM (unit=Hz) is a center frequency of transmission band for the optical signal of the multiplexer and demultiplexer, and Δ
B (unit=Hz) is a 3 dB bandwidth of the transmission band.
- Δ
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15. A method for transmitting and receiving, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned,
wherein when a plurality of channels in accordance with a given wavelength on the optical transmission path is demultiplexed and a plurality of channels in accordance with a given wavelength is multiplexed, and when the wavelength-multiplex optical signal transmitted over the optical transmission path is amplified by an erbium-doped optical fiber amplifier, a signal intensity P (unit=W) of a peak in the outputs of the optical transmission terminal station and the erbium-doped optical fiber amplifier satisfies the condition of P< - Ps (unit=W), when Ps=(0.776λ
3 Aeff D)/(π
2 n2 cto2),wherein λ
(unit=m) is a wavelength, Aeff (unit=m2) is an effective core area of the optical fiber of the optical transmission path, D (unit=s/m/m) is a chromatic dispersive value of the optical fiber, n2 (unit=m2 /n) is a non-linear refractive index of the optical fiber, c (unit=m/s) is a velocity of light, and to (unit=S) is a RZ pulses, andoptical pulses having an equal full-width at half maximum with RZ format of information.
- Ps (unit=W), when Ps=(0.776λ
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16. A method for transmitting and receiving, over an optical transmission path using an optical fiber, wavelength-multiplex signals of a plurality of channels to which different wavelengths are assigned,
wherein said optical pulses having pulse waveforms with an equal RZ pulses are applied to the optical signals, wherein when the wavelength-multiplex signals transmitted over the optical transmission path is multiplexed/demultiplexed by a multiplexer/demultiplexer and the multiplexed/demultiplexed optical signal is amplified by an erbium-doped fiber amplifier, a formula, fsig-fADM≧ - Δ
B/2, is satisfied,wherein fsig (unit=Hz) is an optical frequency of a predetermined optical signal for a predetermined channel of the multiplexer and demultiplexer, fADM (unit=Hz) is a center frequency of transmission band for the optical signal of the multiplexer and demultiplexer, and Δ
B (unit=Hz) is a 3 dB bandwidth of the transmission band.
- Δ
Specification