Single-fiber bidirectional optical transmission apparatus, wavelength division multiplexing device, and optical transmission system

A method, comprising:

• receiving, by a first single-light-source coherent transceiver of an optical transmission apparatus, a first electrical signal from a first apparatus of the optical transmission apparatus;
• converting, by the first single-light-source coherent transceiver, the first electrical signal into a first optical signal;
• sending, by the first single-light-source coherent transceiver, the first optical signal to a first multiplexer/demultiplexer;
• receiving, by a second single-light-source coherent transceiver of the optical transmission apparatus, a second optical signal from the first multiplexer/demultiplexer;
• converting, by the second single-light-source coherent transceiver, the second optical signal into a second electrical signal;
• sending, by the second single-light-source coherent transceiver, the second electrical signal to the first apparatus, wherein a wavelength of the second optical signal is different from a wavelength of the first optical signal;
• receiving, by the second single-light-source coherent transceiver, a third electrical signal from a second apparatus of the optical transmission apparatus, converting the third electrical signal into a third optical signal, and sending the third optical signal to a second multiplexer/demultiplexer, wherein a wavelength of the third optical signal is the same as the wavelength of the second optical signal, and the third optical signal and the second optical signal are sent in opposite directions;
• and
• receiving, by the first single-light-source coherent transceiver, a fourth optical signal from the second multiplexer/demultiplexer, converting the fourth optical signal into a fourth electrical signal, and sending the fourth electrical signal to the second apparatus, wherein a wavelength of the fourth optical signal is the same as the wavelength of the first optical signal, and the first optical signal and the fourth optical signal are sent in opposite directions.

A device, comprising:

• an optical transmission apparatus, wherein the optical transmission apparatus comprises:
• a first single-light-source coherent optical transceiver, configured to:
• receive a first optical signal from a first multiplexer/demultiplexer, convert the first optical signal into a first electrical signal, and send the first electrical signal to a first apparatus;
• and
• a second single-light-source coherent optical transceiver, configured to:
• receive a second electrical signal from the first apparatus, convert the second electrical signal into a second optical signal, and send the second optical signal to the first multiplexer/demultiplexer, wherein a wavelength of the second optical signal is different from a wavelength of the first optical signal;
• receive a third optical signal from a second multiplexer/demultiplexer;
• convert the third optical signal into a third electrical signal;
• and
• send the third electrical signal to a second apparatus, wherein a wavelength of the third optical signal is the same as the wavelength of the second optical signal, and the second optical signal and the third optical signal are sent in opposite directions;
• and
• wherein the first single-light-source coherent optical transceiver is further configured to:
• receive a fourth electrical signal from the second apparatus;
• convert the fourth electrical signal into a fourth optical signal;
• and
• send the fourth optical signal to the second multiplexer/demultiplexer, wherein a wavelength of the fourth optical signal is the same as the wavelength of the first optical signal, and the fourth optical signal and the first optical signal are sent in opposite directions.