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

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 s fourth electrical signal,
• 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 a second optical reception apparatus and outputs the fourth optical signal to a third 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.

An optical communication system comprising an optical transmission apparatus and first to third 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 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 second optical reception apparatus and outputs the fourth optical signal to the third optical reception apparatus.

A method of controlling an optical communication system comprising an optical transmission apparatus and first to third 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,
• 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 second optical reception apparatus and the fourth optical signal is outputted by the output interface to the third optical reception apparatus, and
• wherein each of the optical transmission apparatus and the first to third optical reception apparatuses is controlled according to a state of communication of the optical communication system.

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 to third 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,
• 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 second optical reception apparatus and the fourth optical signal is outputted by the output interface to the third optical reception apparatus, and
• wherein the program causes the computer to execute processing for controlling each of the optical transmission apparatus and the first to third optical reception apparatuses according to a state of communication of the optical communication system.

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 fourth electrical signal,
• 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 third optical signal is outputted by the output interface to a second optical reception apparatus and the fourth optical signal is outputted by the output interface to a third optical reception apparatus.