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US 2002/0154370 A1Published application
Optic relay unit and terminal station in light transmission system
OwnerSatoshi Ishiiinventor
Life of this patent
Estimating the term…
Abstract
An optic relay unit includes (a) an excitation light source to which a predetermined inherent frequency is assigned, (b) an optical amplifier arranged in a transmission line through which a main signal light having a predetermined wavelength is transmitted, to receive the main signal light, the optical amplifier being excited by an excited light emitted from the excitation light source and amplifying the main signal light, and (c) a fault monitoring unit which generates a fault monitoring signal light modulated with the predetermined inherent frequency and having a wavelength different from the predetermined wavelength of the main signal light, when a fault occurs in the excitation light source, and transmits the fault monitoring signal light to the transmission line.
Claims16
An optic relay unit comprising:
- (a) an excitation light source to which a predetermined inherent frequency is assigned;
- (b) an optical amplifier arranged in a transmission line through which a main signal light having a predetermined wavelength is transmitted, to receive said main signal light, said optical amplifier being excited by an excited light emitted from said excitation light source and amplifying said main signal light;
- and
- (c) a fault monitoring unit which generates a fault monitoring signal light modulated with said predetermined inherent frequency and having a wavelength different from said predetermined wavelength of said main signal light, when a fault occurs in said excitation light source, and transmits said fault monitoring signal light to said transmission line.
1 more element
An optic relay unit comprising,
- (a) an excitation light source;
- (b) an optical amplifier arranged in a transmission line through which a main signal light having a predetermined wavelength is transmitted, to receive said main signal light, said optical amplifier being excited by an excited light emitted from said excitation light source and amplifying said main signal light;
- and
- (c) a fault monitoring unit which generates a fault monitoring signal light having an wavelength in advance assigned thereto, different from said predetermined wavelength of said main signal light, when a fault occurs in said excitation light source, and transmits said fault monitoring signal light to said transmission line.
1 more element
A terminal station receiving a signal light through a transmission line in which at least one optic relay unit is arranged,
- said optic relay unit being comprised of:
- (a) an excitation light source to which a predetermined inherent frequency is assigned;
- (b) an optical amplifier arranged in a transmission line through which a main signal light having a predetermined wavelength is transmitted, to receive said main signal light, said optical amplifier being excited by an excited light emitted from said excitation light source and amplifying said main signal light;
- and
- (c) a fault monitoring unit which generates a fault monitoring signal light modulated with said predetermined inherent frequency and having a wavelength different from said predetermined wavelength of said main signal light, when a fault occurs in said excitation light source, and transmits, said fault monitoring signal light to said transmission line,
- said terminal station comprising:
- (a) a spectrum detector which detects spectrum of a received signal light;
- and
- (b) a fault identifier which checks whether a wavelength of a fault monitoring signal light transmitted from said optic relay unit is included in said spectrum detected by said spectrum detector, and which, if said wavelength is included in said spectrum, identifies an excitation light source in which a fault occurs, based on said wavelength and a frequency of said fault monitoring signal light.
6 more elements
A terminal station receiving a signal light through a transmission line in which at least one optic relay unit is arranged,
- said optic relay unit being comprised of;
- (a) an excitation light source to which a predetermined inherent frequency is assigned;
- (b) an optical amplifier arranged in a transmission line through which a main signal light having a predetermined wavelength is transmitted, to receive said main signal light, said optical amplifier being excited by an excited light emitted from said excitation light source and amplifying said main signal light;
- and
- (c) a fault monitoring unit which generates a fault monitoring signal light modulated with said predetermined inherent frequency and having a wavelength different from said predetermined wavelength of said main signal light, when a fault occurs in said excitation light source, and transmits said fault monitoring signal light to said transmission line,
- said terminal station comprising:
- (a) a spectrum detector which detects spectrum of a received signal light;
- and
- (b) a fault identifier which checks whether a wavelength of a fault monitoring signal light transmitted from said optic relay unit is included in said spectrum detected by said spectrum detector, and which, if said wavelength is included in said spectrum, identifies an excitation light source in which a fault occurs, based on said wavelength of said fault monitoring signal light.
6 more elements
A light transmission system comprising:
- (a) a plurality of optic relay units each of which includes an excitation light source to which a frequency different from frequencies assigned to other excitation light sources is assigned, and which transmits a fault monitoring signal light having a frequency modulated with a frequency assigned to an excitation light source in which a fault occurs;
- and
- (b) a terminal station which receives a signal light through said optic relay units, detects spectrum of the thus received signal light, checks whether a wavelength of said fault monitoring signal light transmitted from said optic relay unit is included in the thus detected spectrum, and, if said wavelength is included in said spectrum, identifies an excitation light source in which a fault occurs, based on said frequency of said fault monitoring signal light.
A light transmission system comprising:
- (a) a plurality of optic relay units each of which includes an excitation light source which transmits a fault monitoring signal light having a wavelength inherent thereto, if a fault occurs in said excitation light source;
- and
- (b) a terminal station which receives a signal light through said optic relay units, detects spectrum of the thus received signal light, checks whether a wavelength of said fault monitoring signal light transmitted from said optic relay unit is included in the thus detected spectrum, and, if said wavelength is included in said spectrum, identifies an excitation light source in which a fault occurs, based on said wavelength of said fault monitoring signal light.
A method of identifying an excitation light source in which a fault occurs, in a light transmission system including a transmission line in which a plurality of optic relay units each including an excitation light source is arranged,
- said method comprising the steps of:
- (a) assigning a frequency to each of the excitation light sources of said optic relay units such that the thus assigned frequencies are different from one another;
- (b) transmitting a fault monitoring signal light to said transmission line which fault monitoring signal light has a frequency modulated with a frequency assigned to an excitation light source in which a fault occurs;
- (c) detecting spectrum of a signal light received through said transmission line;
- and
- (d) checking whether a wavelength of said fault monitoring signal light is included in said spectrum detected in said step (c), and, if said wavelength is included in said spectrum, identifying an excitation light source in which a fault occurs, based on said frequency of said fault monitoring signal light.
3 more elements
A method of identifying an excitation light source in which a fault occurs, in a light transmission system including a transmission line in which a plurality of optic relay units each including an excitation light source is arranged,
- said method comprising the steps of:
- (a) transmitting a fault monitoring signal light to said transmission line which fault monitoring signal light has a wavelength if a fault occurs in an excitation light source, said wavelength being inherent to said excitation light source;
- (b) detecting spectrum of a signal light received through said transmission line;
- and
- (c) checking whether a wavelength of said fault monitoring signal light is included in said spectrum detected in said step (b), and, if said wavelength is included in said spectrum, identifying an excitation light source in which a fault occurs, based on said wavelength of said fault monitoring signal light.
2 more elements
Dependencies are inferred from the claim text.