A communication module includes a laser driving unit (LDU) and one or more multifunction illumination units. The one or more multifunction illumination units are be coupled to the LDU with an electrical connection and configured to transmit both electrical power and data.

An object is to provide an optical transmission apparatus in which dummy lights can be arranged according to an arrangement of optical signals. A plurality of optical signals of different frequencies arranged in a frequency grid are input to a multiplexing unit and the multiplexing unit multiplexes the input optical signals. A dummy light output unit identifies a dummy light to be arranged in the frequency grid based on the plurality of optical signals and outputs the dummy light. A multiplexing unit multiplexes an optical signal multiplexed by the multiplexing unit and the dummy light output from the dummy light output unit to output a wavelength-multiplexed optical signal L.

An object is to provide an optical transmission apparatus in which dummy lights can be arranged according to an arrangement of optical signals. A plurality of optical signals of different frequencies arranged in a frequency grid are input to a multiplexing unit and the multiplexing unit multiplexes the input optical signals. A dummy light output unit identifies a dummy light to be arranged in the frequency grid based on the plurality of optical signals and outputs the dummy light. A multiplexing unit multiplexes an optical signal multiplexed by the multiplexing unit and the dummy light output from the dummy light output unit to output a wavelength-multiplexed optical signal L.

Provided is a wavelength path communication node device with no collision of wave lengths and routes, capable of outputting arbitrary wavelengths, and capable of outputting them to arbitrary routes. An add/drop multiplexer (11) includes a communication unit (101) that communicates an optical signal with at least one client device and at least one network and a control unit (102) that indicates a transfer destination of the optical signal according to an attribute of the received optical signal to the communication unit (101). The control unit (102) indicates an attenuation amount of the optical signal to the communication unit (101) for each connected device. When a connected device is changed, the control unit (102) instructs the communication unit (101) to change the attenuation amount. The communication unit (101) attenuates the optical signal with the attenuation amount indicated by the control unit (102) and transfers the attenuated optical signal to a transfer destination.

Provided is a wavelength path communication node device with no collision of wave lengths and routes, capable of outputting arbitrary wavelengths, and capable of outputting them to arbitrary routes. An add/drop multiplexer (11) includes a communication unit (101) that communicates an optical signal with at least one client device and at least one network and a control unit (102) that indicates a transfer destination of the optical signal according to an attribute of the received optical signal to the communication unit (101). The control unit (102) indicates an attenuation amount of the optical signal to the communication unit (101) for each connected device. When a connected device is changed, the control unit (102) instructs the communication unit (101) to change the attenuation amount. The communication unit (101) attenuates the optical signal with the attenuation amount indicated by the control unit (102) and transfers the attenuated optical signal to a transfer destination.

The present invention discloses an optical signal frequency calibration method and device. The method includes: receiving a first optical signal that experiences a frequency offset and that is generated by a laser in a transmitter of an access node; receiving a reference optical signal sent by a local oscillator; calculating a difference between a specified frequency difference and a frequency difference between the reference optical signal and the first optical signal; and performing frequency calibration on the first optical signal according to the difference, modulating to-be-sent uplink data by using the calibrated first optical signal, and sending the modulated uplink data to a primary node.

An object is to provide an optical communication system and an optical communication method that are capable of, when assigning wavelengths on a per-service basis and providing services on a per-area basis, preventing degradation of signal quality due to linear crosstalk and preventing an increase in cost and size. An optical communication system according to the present invention includes an optical splitter 300 connecting N first ports and M second ports by a combination of 2×2 fiber optical splitters, N and M each being an integer of two or more, where wavelengths of optical signals to be received are limited for each group of optical receivers 106, by using a correlation between a fused extension length of at least one 2×2 fiber optical splitter directly connected to the first port, among the 2×2 fiber optical splitters, and wavelength output characteristics of the second port of the optical splitter 300.

An object is to provide an optical communication system and an optical communication method that are capable of, when assigning wavelengths on a per-service basis and providing services on a per-area basis, preventing degradation of signal quality due to linear crosstalk and preventing an increase in cost and size. An optical communication system according to the present invention includes an optical splitter 300 connecting N first ports and M second ports by a combination of 2×2 fiber optical splitters, N and M each being an integer of two or more, where wavelengths of optical signals to be received are limited for each group of optical receivers 106, by using a correlation between a fused extension length of at least one 2×2 fiber optical splitter directly connected to the first port, among the 2×2 fiber optical splitters, and wavelength output characteristics of the second port of the optical splitter 300.

An optical phased array, includes, in part, K beam processors each adapted to receive a different one of K optical signals and generate N optical signals in response. The difference between the phases of optical signals a.sub.LM and a.sub.L(M+1) is the same for all Ms, where M is an integer ranging from 1 to N−1 defining the signals generated by a beam processor, and L is an integer ranging from 1 to K defining the beam processor generating the K optical signals. The transmitter further includes, in part, a combiner adapted to receive the N×K optical signals from the K beam processors and combine the K optical signals from different ones of the K beam processors to generate N optical signals. The transmitter further includes, in part, N radiating elements each adapted to transmit one of the N optical signals.

An optical phased array, includes, in part, K beam processors each adapted to receive a different one of K optical signals and generate N optical signals in response. The difference between the phases of optical signals a.sub.LM and a.sub.L(M+1) is the same for all Ms, where M is an integer ranging from 1 to N−1 defining the signals generated by a beam processor, and L is an integer ranging from 1 to K defining the beam processor generating the K optical signals. The transmitter further includes, in part, a combiner adapted to receive the N×K optical signals from the K beam processors and combine the K optical signals from different ones of the K beam processors to generate N optical signals. The transmitter further includes, in part, N radiating elements each adapted to transmit one of the N optical signals.