An optical transmitter based on optical time division multiplexing is disclosed, which may solve the issues of complex structure and operation of a multilevel-OTDM-based optical transmitter while using a multilevel signal modulation format and OTDM technology that may increase the transmission rate of an optical transmitter with limited bandwidth.

An optical transmitter based on optical time division multiplexing is disclosed, which may solve the issues of complex structure and operation of a multilevel-OTDM-based optical transmitter while using a multilevel signal modulation format and OTDM technology that may increase the transmission rate of an optical transmitter with limited bandwidth.

Various embodiments of the disclosed PON system enable approximate leveling of the optical-modulation amplitudes in a sequence of optical bursts received by a system's OLT from a plurality of ONUs. Some embodiments additionally enable approximate leveling of the average optical power, received at the OLT from different ONUs, in such a sequence. Some embodiments may rely on control messaging between the OLT and ONUs to perform one or both types of leveling. The disclosed leveling may advantageously provide an effective tool for optimizing upstream transmission for high-speed TDM-PONs.

This application provides an optical emission apparatus, an optical communication system, and an optical communication method. Light beams of N optical emission units in the optical emission apparatus are adjusted, so that an optical power of entering an optical receiving apparatus is maximized, and impact of a speckle caused by turbulence is minimized, thereby improving receiving efficiency of an optical antenna. The optical emission apparatus includes a first optical splitter and N optical emission units, where N is an integer greater than 1; the first optical splitter is configured to transmit received same signal light to the N optical emission units; and the N optical emission units are configured to output the signal light from the first optical splitter, to obtain light beams distributed based on a preset proportion.

Provided is an optical communication system comprising a polarization-diversity optical power supply capable of supplying light over a non-polarization-maintaining optical fiber to a polarization-sensitive modulation device. In an example embodiment, the polarization-diversity optical power supply operates to accommodate random polarization fluctuations within the non-polarization-maintaining optical fiber and enables an equal-power split at a passive polarization splitter preceding the polarization-sensitive modulation device.

Provided is an optical communication system comprising a polarization-diversity optical power supply capable of supplying light over a non-polarization-maintaining optical fiber to a polarization-sensitive modulation device. In an example embodiment, the polarization-diversity optical power supply operates to accommodate random polarization fluctuations within the non-polarization-maintaining optical fiber and enables an equal-power split at a passive polarization splitter preceding the polarization-sensitive modulation device.

A communication system includes a first device and a second device connected through an electro-optical composite cable. The electro-optical composite cable includes an optical fiber and a power supply cable. The optical fiber is used to transmit a data signal. The power supply cable is used to transmit a direct current. The first device is configured to send a first alternating-current signal to the second device through the power supply cable. The second device is configured to switch a running status based on the first alternating-current signal.

A communication system includes a first device and a second device connected through an electro-optical composite cable. The electro-optical composite cable includes an optical fiber and a power supply cable. The optical fiber is used to transmit a data signal. The power supply cable is used to transmit a direct current. The first device is configured to send a first alternating-current signal to the second device through the power supply cable. The second device is configured to switch a running status based on the first alternating-current signal.

An optical communication system includes an optical transmitter and one or more processors. The optical transmitter is configured to output an optical signal, and includes an average-power-limited optical amplifier, such as an erbium-doped fiber amplifier (EDFA). The one or more processors are configured to receive optical signal data related to a received power for a communication link from a remote communication system and determine that the optical signal data is likely to fall below a minimum received power within a time interval. In response to the determination, the one or more processors are configured to determine a duty cycle of the optical transmitter based on a minimum on-cycle length and a predicted EDFA output power and operate the optical transmitter using the determined duty cycle to transmit an on-cycle power that is no less than the minimum required receiver power for error-free operation of the communication link.

An optical communication system includes an optical transmitter and one or more processors. The optical transmitter is configured to output an optical signal, and includes an average-power-limited optical amplifier, such as an erbium-doped fiber amplifier (EDFA). The one or more processors are configured to receive optical signal data related to a received power for a communication link from a remote communication system and determine that the optical signal data is likely to fall below a minimum received power within a time interval. In response to the determination, the one or more processors are configured to determine a duty cycle of the optical transmitter based on a minimum on-cycle length and a predicted EDFA output power and operate the optical transmitter using the determined duty cycle to transmit an on-cycle power that is no less than the minimum required receiver power for error-free operation of the communication link.