Optical demultiplexer, optical separation device, optical transmission system, and optical transmission method

An optical separator, comprising:

• a plurality of optical gate switches, each of which is configured to perform i) an on operation for transmitting an optical signal of a predetermined single wavelength in a predetermined time slot and ii) an off operation for blocking an optical signal,
• each of the plurality of optical gate switches performing, when a multiplexed optical signal obtained by multiplexing optical signals of a plurality of wavelengths by time-division multiplexing is input, the on operation during a corresponding predetermined time slot when the time-division multiplexing is performed, to separate an optical signal of a corresponding single wavelength stored in the corresponding predetermined time slot;
• and
• a cAWG including a plurality of input ports and a plurality of output ports and configured to input the optical signal of the predetermined single wavelength transmitted through the plurality of optical gate switches from the plurality of input ports, and cycle and output the input optical signal of the predetermined single wavelength from the plurality of output ports in a predetermined order.

An optical transmission method of an optical transmission system, the method comprising:

• transmitting optical signals of a plurality of wavelengths from a plurality of transmission nodes;
• multiplexing the transmitted optical signals of a plurality of wavelengths by time-division multiplexing or wavelength-division multiplexing in addition to time-division multiplexing by one optical coupler;
• transmitting the multiplexed optical signal to a second optical coupler via an optical transmission line;
• branching the transmitted multiplexed optical signal by the second optical coupler;
• and
• receiving optical signals obtained by the branching by a plurality of reception nodes, wherein
• an optical demultiplexer for demultiplexing the multiplexed optical signal transmitted in the optical transmission line for each wavelength is provided for the plurality of reception nodes,
• the optical demultiplexer performs:
• transmitting or blocking the multiplexed optical signal transmitted in the optical transmission line;
• and
• demultiplexing the transmitted multiplexed optical signal for each wavelength, and cycling and delivering optical signals obtained by the demultiplexing to the plurality of reception nodes in a predetermined order.