1. An optical amplifier comprising:
a front-stage amplifier that amplifies an input optical signal;
an attenuator that attenuates an output of the front-stage amplifier;
a back-stage amplifier that amplifies an output of the attenuator;
a control parameter determination unit that determines a control parameter for controlling the front-stage amplifier, the back-stage amplifier, and the attenuator so as to correct a spectral slope caused by stimulated Raman scattering of the optical signal based on network information received from another device; and
a control unit that controls the front-stage amplifier, the back-stage amplifier, and the attenuator based on the control parameter.
2. The optical amplifier according to claim 1, further comprising a network information reception unit that receives the network information from a node device that received the network information from a network management device.
3. The optical amplifier according to claim 2, wherein the network information is transmitted from the network management device to the node device at a predetermined time interval, and the control parameter determination unit determines the control parameter every the predetermined time interval.
4. The optical amplifier according to claim 2, wherein the network information is reported from an optical cross-connect device to the network management device.
5. The optical amplifier according to claim 1, wherein the network information comprises the number of multiplexed wavelengths of the optical signal that the optical amplifier itself amplifies.
6. The optical amplifier according to claim 1, wherein the control parameter comprises a total optical output power of the optical amplifier obtained by multiplying an output per channel by the number of multiplexed wavelengths.
7. An optical transmission system comprising:
node devices that form a communication network;
a network management device that acquires network information; and
an optical amplifier that amplifies an optical signal between the node devices,
wherein the optical amplifier comprises:
a front-stage amplifier that amplifies an input optical signal;
an attenuator that attenuates an output of the front-stage amplifier;
a back-stage amplifier that amplifies an output of the attenuator;
a network information reception unit that receives the network information from a node device that received the network information from the network management device;
a control parameter determination unit that determines a control parameter for controlling the front-stage amplifier, the back-stage amplifier, and the attenuator so as to correct a spectral slope caused by stimulated Raman scattering of the optical signal based on the received network information; and
a control unit that controls the front-stage amplifier, the back-stage amplifier, and the attenuator based on the control parameter.
8. A control method for an optical amplifier comprising:
determining a control parameter for controlling a front-stage amplifier that amplifies an input optical signal, an attenuator that attenuates an output of the front-stage amplifier, and a back-stage amplifier that amplifies an output of the attenuator so as to correct a spectral slope caused by stimulated Raman scattering of the optical signal based on network information received from another device; and
controlling the front-stage amplifier, the back-stage amplifier, and the attenuator, which are provided in the optical amplifier, based on the control parameter.
9. The optical amplifier according to claim 3, wherein the network information is reported from an optical cross-connect device to the network management device.
10. The optical amplifier according to claim 2, wherein the network information comprises the number of multiplexed wavelengths of the optical signal that the optical amplifier itself amplifies.
11. The optical amplifier according to claim 3, wherein the network information comprises the number of multiplexed wavelengths of the optical signal that the optical amplifier itself amplifies.
12. The optical amplifier according to claim 4, wherein the network information comprises the number of multiplexed wavelengths of the optical signal that the optical amplifier itself amplifies.
13. The optical amplifier according to claim 2, wherein the control parameter comprises a total optical output power of the optical amplifier obtained by multiplying an output per channel by the number of multiplexed wavelengths.
14. The optical amplifier according to claim 3, wherein the control parameter comprises a total optical output power of the optical amplifier obtained by multiplying an output per channel by the number of multiplexed wavelengths.
15. The optical amplifier according to claim 4, wherein the control parameter comprises a total optical output power of the optical amplifier obtained by multiplying an output per channel by the number of multiplexed wavelengths.
16. The optical amplifier according to claim 5, wherein the control parameter comprises a total optical output power of the optical amplifier obtained by multiplying an output per channel by the number of multiplexed wavelengths.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system for automatically moving a motor of a boat to a position to avoid damage to the motor in response to change in the depth of the water over which the boat is traveling, said system comprising:
a) means for sensing the depth of the water being traversed and
b) means for calculating the necessary position of the motor to extend into the water at a safe depth less than the depth sensed by the sensing means and
c) means for moving said motor to said position.
2. The system as defined in claim 1 and in which said moving means includes trim adjustment means for moving the motor away from and toward the boat.