Provided is an optical transceiver including: a controller configured to output firmware update data for updating firmware of another optical transceiver connected to the optical transceiver through an optical cable; and a transmitter configured to generate an optical signal by superposing input payload data and the firmware update data, and to transmit the optical signal to the other optical transceiver. According to embodiments, the firmware of a remote optical transceiver at a remote location is automatically updated without affecting payload data, which is information to be transmitted.

Provided is an optical transceiver including: a controller configured to output firmware update data for updating firmware of another optical transceiver connected to the optical transceiver through an optical cable; and a transmitter configured to generate an optical signal by superposing input payload data and the firmware update data, and to transmit the optical signal to the other optical transceiver. According to embodiments, the firmware of a remote optical transceiver at a remote location is automatically updated without affecting payload data, which is information to be transmitted.

Techniques are described for implementing an out-of-band communication channel used to exchange control channel information in sub-carrier-based optical communication systems. In an example implementation, an optical communication system includes a primary transceiver, a component, and secondary transceivers. The primary transceiver is operable to supply first optical subcarriers to an optical communication path, the first optical subcarriers being amplitude modulated at a first frequency to carry first control information and amplitude modulated at a second frequency to carry second control information. The component is operable to be coupled to the optical communication path and includes circuitry operable to detect the first control information. The secondary transceivers are coupled to a terminal end of the optical communication path. At least one of the secondary transceivers is operable to detect the second control information and block the first control information.

Techniques are described for implementing an out-of-band communication channel used to exchange control channel information in sub-carrier-based optical communication systems. In an example implementation, an optical communication system includes a primary transceiver, a component, and secondary transceivers. The primary transceiver is operable to supply first optical subcarriers to an optical communication path, the first optical subcarriers being amplitude modulated at a first frequency to carry first control information and amplitude modulated at a second frequency to carry second control information. The component is operable to be coupled to the optical communication path and includes circuitry operable to detect the first control information. The secondary transceivers are coupled to a terminal end of the optical communication path. At least one of the secondary transceivers is operable to detect the second control information and block the first control information.

An apparatus is provided for using a square wave digital chirp signal for optical chirp range detection. A laser source emits an optical signal and a RF waveform generator generates an input digital chirp signal based on the square wave digital chirp signal. A frequency of the optical signal is modulated based on the input digital chirp signal. A splitter divides the optical signal into a transmit optical signal and a reference optical signal. A detector combines the reference optical signal and a return optical signal from an object. The detector generates an electrical output signal based on the combined reference optical signal and the return optical signal. A processor determines a range to the object based on a characteristic of a Fourier transform the electrical output signal. A method is also provided for using the square wave digital chirp signal for optical chirp range detection.

An apparatus is provided for using a square wave digital chirp signal for optical chirp range detection. A laser source emits an optical signal and a RF waveform generator generates an input digital chirp signal based on the square wave digital chirp signal. A frequency of the optical signal is modulated based on the input digital chirp signal. A splitter divides the optical signal into a transmit optical signal and a reference optical signal. A detector combines the reference optical signal and a return optical signal from an object. The detector generates an electrical output signal based on the combined reference optical signal and the return optical signal. A processor determines a range to the object based on a characteristic of a Fourier transform the electrical output signal. A method is also provided for using the square wave digital chirp signal for optical chirp range detection.

A fiber enabled optical wireless communication (FE-OWC) system and method is provided. An optical antenna composed of an optical fiber transceiving port array and a lens or a reflecting mirror is used to generate optical beams in different directions, such that full-beam coverage of a communication area is implemented. The optical antenna is connected to an optical chain by an optical fiber, the optical chain realizes mutual conversion of an optical signal and an electrical signal, and a baseband signal processing unit which is in electrical signal connection with the optical chain realizes user scheduling, transceiving signal processing, etc. Multi-user multiple-input multiple-output (MIMO) or massive MIMO or beam division multiple access optical wireless communication between a base station and user terminals is implemented by using the optical beams. The FE-OWC system and method may support ultra-high-rate user data transmission and system throughput, and have a low complexity.

A network device generates first resonant light used to carry information; and the network device sends the first resonant light to a terminal by using a resonant cavity component, where the resonant cavity component of the network device and a resonant cavity component of the terminal form an open resonant cavity. In wireless optical communication, an information transmission rate can be greatly improved by using a resonant light multiplexing technology. This application further discloses a network device and a terminal that can implement the foregoing wireless optical communication method.

Disclosed herein is a transponder comprising a transmitter and a receiver. The transponder further comprises a receiver input amplifier, a bypass line, and a control unit configured for determining the performance of the transponder in relation to an OSNR related parameter, by controlling the transponder to generate a noise signal to be received by the receiver. The receiver input amplifier is operated to thereby cause ASE in the receiver input amplifier to facilitate the determination. A test signal is generated at the transmitter Said noise signal and said test signal, and/or one or more respective replicas thereof, are superimposed to form a combined signal to be received by said receiver to further facilitate determination of said performance related parameter based on said combined signal, wherein for generating said combined signal, said test signal is fed from the transmitter to the receiver by means of said bypass line.

Disclosed herein is a transponder comprising a transmitter and a receiver. The transponder further comprises a receiver input amplifier, a bypass line, and a control unit configured for determining the performance of the transponder in relation to an OSNR related parameter, by controlling the transponder to generate a noise signal to be received by the receiver. The receiver input amplifier is operated to thereby cause ASE in the receiver input amplifier to facilitate the determination. A test signal is generated at the transmitter Said noise signal and said test signal, and/or one or more respective replicas thereof, are superimposed to form a combined signal to be received by said receiver to further facilitate determination of said performance related parameter based on said combined signal, wherein for generating said combined signal, said test signal is fed from the transmitter to the receiver by means of said bypass line.