Optical transmission apparatus, optical reception apparatus, optical communications apparatus, optical communication system, and methods of controlling them

1. An optical transmission apparatus comprising:

a signal processor configured to convert a first data stream into a first electrical signal and a second electrical signal;

a first optical transmitter configured to convert the first electrical signal into a first optical signal;

a second optical transmitter configured to convert the second electrical signal into a second optical signal; and

an output interface configured to output the first optical signal and the second optical signal to a first optical reception apparatus,

wherein:

the signal processor converts a second data stream into a third electrical signal and converts a third data stream into a fourth electrical signal, the second and third data streams transmitted via different paths;

the first optical transmitter converts the third electrical signal into a third optical signal;

the second optical transmitter converts the fourth electrical signal into a fourth optical signal; and

the output interface outputs the third optical signal to the first optical reception apparatus and outputs the fourth optical signal to a second optical reception apparatus.

2. The optical transmission apparatus according to claim 1 , wherein the third optical signal is generated by a first sub-carrier and the fourth optical signal is generated by a second sub-carrier, and predetermined parameters of the first and second sub-carriers are allocated in such a way that they do not overlap with each other.

3. The optical transmission apparatus according to claim 2 , wherein:

each of the plurality of parameters comprises a plurality of parameters, and

the first and second sub-carriers are arranged in such a way that they do not overlap with each other.

4. The optical transmission apparatus according to claim 2 , wherein each of the predetermined parameters comprises at least one of a wavelength, a polarization, and a time.

5. The optical transmission apparatus according to claim 1 , wherein the third and fourth optical signals have wavelengths different from each other.

6. The optical transmission apparatus according to claim 1 , wherein:

the first optical transmitter is supplied with a first sub-carrier from a first light source, and the second optical transmitter is supplied with a second sub-carrier from a second light source.

7. The optical transmission apparatus according to claim 5 , further comprising:

a single light source; and

a sub-carrier generator configured to generate the first and second sub-carriers using light generated in the single light source and supplies the first and second sub-carriers that have been generated to the first and second optical transmitters, respectively.

8. The optical transmission apparatus according to claim 7 , wherein the sub-carrier generator modulates light generated in the single light source using orthogonal frequency division multiplexing to generate the first sub-carrier and the second sub-carrier that are perpendicular to each other.

9. The optical transmission apparatus according to claim 1 , wherein:

when the first and second electrical signals are converted based on the first data stream, data that has been serial-parallel converted is supplied to the first and second optical transmitters, and

the first and second optical transmitters transmit the data that has been serial-parallel converted in parallel.

10. The optical transmission apparatus according to claim 1 , further comprising:

first and second optical multiplexers that

correspond to the first and second optical reception apparatuses, respectively, and

are configured to multiplex the third and fourth optical signals output from the output interface, respectively.

11. The optical transmission apparatus according to claim 10 , wherein the output interface comprises a first and second output interfaces that respectively correspond to the first and second optical transmitters and switch output destinations of the third and fourth optical signals output from the first and second optical transmitters to the first optical multiplexer and the second optical multiplexer, respectively.

12. The optical transmission apparatus according to claim 1 , further comprising:

an optical multiplexer that multiplexes the third and fourth optical signals output from the first and second optical transmitters; and

an optical demultiplexer that selectively outputs the third and fourth optical signals included in the multiplexed optical signal output from the optical multiplexer to the first and second optical reception apparatuses.

13. An optical communication apparatus comprising:

a signal processor configured to convert a first data stream into a first electrical signal and a second electrical signal;

a first optical transmitter configured to convert the first electrical signal into a first optical signal;

a second optical transmitter configured to convert the second electrical signal into a second optical signal;

a first output interface configured to output the first optical signal and the second optical signal to a first optical reception apparatus, wherein:

the signal processor converts a second data stream into a third electrical signal and converts a third data stream into a fourth electrical signal, the second and third data streams transmitted via different paths,

the first optical transmitter converts the third electrical signal into a third optical signal,

the second optical transmitter converts the fourth electrical signal into a fourth optical signal, and

the first output interface outputs the third optical signal to the first optical reception apparatus and outputs the fourth optical signal to a second optical reception apparatus;

first and second receivers configured to receive sub-carrier reception signals; and

a second output interface configured to output a first sub-carrier reception signal and a second sub-carrier reception signal that have been input to the first and second receivers, wherein:

when the first and second sub-carrier reception signals correspond to the first and second optical signals respectively, the second output interface receives the first and second sub-carrier reception signals via one path and outputs the first sub-carrier reception signal to the first receiver and the second sub-carrier reception signal to the second receiver, and

when the first sub-carrier reception signal and the second sub-carrier reception signal correspond to the third and fourth optical signals respectively, the second output interface receives the first and second sub-carrier reception signals via paths different from each other and outputs the first sub-carrier reception signal to the first receiver and the second sub-carrier reception signal to the second receiver.

14. An optical communication system comprising an optical transmission apparatus and first and second optical reception apparatuses, wherein:

the optical transmission apparatus comprises:

a signal processor configured to convert a first data stream into a first electrical signal and a second electrical signal;

a first optical transmitter configured to convert the first electrical signal into a first optical signal;

a second optical transmitter configured to convert the second electrical signal into a second optical signal; and

an output interface configured to output the first optical signal and the second optical signal to the first optical reception apparatus,

wherein:

the signal processor converts a second data stream into a third electrical signal and converts a third data stream into a fourth electrical signal, the second and third data streams transmitted via different paths;

the first optical transmitter converts the third electrical signal into a third optical signal;

the second optical transmitter converts the fourth electrical signal into a fourth optical signal; and

the output interface outputs the third optical signal to the first optical reception apparatus and outputs the fourth optical signal to a second optical reception apparatus.

15. The optical communication system according to claim 14 , wherein the third optical signal is generated by a first sub-carrier and the fourth optical signal is generated by a second sub-carrier, and predetermined parameters of the first and second sub-carriers are allocated in such a way that they do not overlap with each other.

16. The optical communication system according to claim 15 , wherein:

each of the plurality of parameters comprises a plurality of parameters, and

the first and second sub-carriers are arranged in such a way that they do not overlap with each other.

17. The optical communication system according to claim 15 , wherein each of the predetermined parameters comprises at least one of a wavelength, a polarization, and a time.

18. The optical communication system according to claim 14 , wherein the third and fourth optical signals have wavelengths different from each other.

19. The optical communication system according to claim 14 , wherein:

the first optical transmitter is supplied with a first sub-carrier from a first light source, and the second optical transmitter is supplied with a second sub-carrier from a second light source.

20. The optical communication system according to claim 18 , further comprising:

a single light source; and

a sub-carrier generator configured to generate the first and second sub-carriers using light generated in the single light source and supplies the first and second sub-carriers that have been generated to the first and second optical transmitters, respectively.

21. The optical communication system according to claim 20 , wherein the sub-carrier generator modulates light generated in the single light source using orthogonal frequency division multiplexing to generate the first sub-carrier and the second sub-carrier that are perpendicular to each other.

22. The optical communication system according to claim 14 , wherein:

when the first and second electrical signals are converted based on the first data stream, data that has been serial-parallel converted is supplied to the first and second optical transmitters, and

the first and second optical transmitters transmit the data that has been serial-parallel converted in parallel.

23. The optical communication system according to claim 14 , wherein the optical transmission apparatus further comprises:

first and second optical multiplexers that

correspond to the first and second optical reception apparatuses, respectively, and

multiplex the third and fourth optical signals output from the output interface, respectively.

24. The optical communication system according to claim 23 , wherein the output interface comprises a first and second output interfaces that respectively correspond to the first and second optical transmitters and switch output destinations of the third and fourth optical signals output from the first and second optical transmitters to the first optical multiplexer or the second optical multiplexer, respectively.

25. The optical communication system according to claim 14 , wherein the optical transmission apparatus further comprises:

an optical multiplexer that multiplexes the third and fourth optical signals output from the first and second optical transmitters, respectively; and

an optical demultiplexer that selectively outputs the third and fourth optical signals included in the multiplexed optical signal output from the optical multiplexer to the first and second optical reception apparatuses.

26. A method of controlling an optical communication system comprising an optical transmission apparatus and first and second optical reception apparatuses, comprising:

converting, by a signal processor, a first data stream into a first electrical signal and a second electrical signal;

converting, by a first optical transmitter, the first electrical signal into a first optical signal;

converting, by a second optical transmitter, the second electrical signal into a second optical signal; and

outputting, by an output interface, the first optical signal and the second optical signal to the first optical reception apparatus,

wherein the signal processor converts a second data stream into a third electrical signal and converts a third data stream into a fourth electrical signal, the second and third data stream transmitted via different paths,

wherein the third electrical signal is converted by the first optical transmitter into a third optical signal,

wherein the fourth electrical signal is converted by the second optical transmitter into a fourth optical signal,

wherein the third optical signal is outputted by the output interface to the first optical reception apparatus and the second optical signal is outputted by the output interface to the second optical reception apparatus, and

wherein each of the optical transmission apparatus and the first and second optical reception apparatuses is controlled according to a state of communication of the optical communication system.

27. A non-transitory computer-readable storage medium storing a program for causing a computer to perform a method for controlling an optical communication system comprising an optical transmission apparatus and first and second optical reception apparatuses, wherein the method comprises:

controlling a signal processor to convert a first data stream into a first electrical signal and a second electrical signal;

converting, by a first optical transmitter, the first electrical signal into a first optical signal;

converting, by a second optical transmitter, the second electrical signal into a second optical signal; and

outputting, by an output interface, the first optical signal and the second optical signal to the first optical reception apparatus,

wherein the signal processor converts a second data stream into a third electrical signal and converts a third data stream into a fourth electrical signal, the second and third data streams transmitted via different paths,

wherein the third electrical signal is converted by the first optical transmitter into a third optical signal,

wherein the fourth electrical signal is converted by the second optical transmitter into a fourth optical signal,

wherein the third optical signal is outputted by the output interface to the first optical reception apparatus and the second optical signal is outputted by the output interface to the second optical reception apparatus, and

wherein the program causes the computer to execute processing for controlling each of the optical transmission apparatus and the first and second optical reception apparatuses according to a state of communication of the optical communication system.

28. An optical transmission method comprising:

converting, by a signal processor, a first data stream into a first electrical signal and a second electrical signal;

converting, by a first optical transmitter, the first electrical signal into a first optical signal;

converting, by a second optical transmitter, the second electrical signal into a second optical signal; and

outputting, by an output interface, the first optical signal and the second optical signal to a first optical reception apparatus,

wherein the signal processor converts a second data stream into a third electrical signal and converts a third data stream into the third electrical signal, the second and third data streams transmitted via different paths,

wherein the third electrical signal is converted by the first optical transmitter into a third optical signal,

wherein the fourth electrical signal is converted by the second optical transmitter into a fourth optical signal, and

wherein the first optical signal is outputted by the output interface to the first optical reception apparatus and the second optical signal is outputted by the output interface to the second optical reception apparatus.