A distributed Automatic Power Optimization (APO) system and method are provided. The distributed APO system includes: one or more APO modules and a network management system. The one or more APO modules belong to one or more pre-divided APO links. Each APO module in the one or more APO modules belongs to only one APO link. The APO module is configured to, when the APO link to which the APO module belongs is triggered to perform power regulation, regulate a power attenuation or a gain between the two adjacent stations corresponding to the APO module and report a regulation result. The network management system is configured to, when learning that all of one or more APO modules in one APO link are successful in regulation, if there is a next APO link of the APO link, trigger the next APO link of the APO link to perform power regulation.

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.

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.

Described are systems, devices, and techniques for extending wireless networks and associated systems, devices, and techniques for determination of optimal locations of a wireless range extender, such as by evalauating a quality of a wireless signal originating from a wireless gateway or access device and determining whether an alternative placement of a wireless range extender would result in improved quality. Also described are systems, devices, and techniques for automatically grouping multiple bands of a single wireless access device as well as systems, devices, and techniques that simplify connection of wireless devices to a wireless access device, such as by evaluating wireless messages transmitted on different bands to determine that the wireless messages originate from the same wireless access device.

A method for realizing precise gain control for a hybrid fibre amplifier, and a hybrid fibre amplifier, in which by an erbium-doped fibre amplifier firstly outputting a constant power, a comparable source signal optical power is provided for a raman fibre amplifier of a next stage. A feedback for the gain control may be formed by comparing a source signal optical power calculated after starting pumping of the Raman fibre amplifier and a source signal optical power detected after pumping stops, thereby greatly improving gain control precision of the Raman fibre amplifier. Moreover, the erbium-doped fibre amplifier parts of all the hybrid fibre amplifiers may simultaneously output a constant optical power, and the Raman amplifier parts of all the hybrid fibre amplifiers may simultaneously start calibration, so that the time for starting operation of the entire system may be improved greatly.

Aspects of an optical communications network are described that include two or more optical fibers arranged to allow communication in the same or in opposite directions. The optical network includes a first optical amplifier coupled to the first optical fiber, a second optical amplifier coupled to the second optical fiber, and an optical coupler that allows excess optical power from the first optical fiber to be provided for amplification of signals traversing the second optical fiber. The disclosed systems and devices thus enable excess power from one channel to be utilized to enable amplification of signals traveling on a different channel.

A node (10) includes multiplexing unit (11) that multiplexes a plurality of subcarrier signals for performing optical wavelength multiplexing communication into a wavelength group signal; output unit (12) that outputs the multiplexed wavelength group signal to an optical transmission line; pre-multiplexing level correction unit (13) that corrects a level deviation between the subcarrier signals before the multiplexing based on an optical level of the wavelength group signal in the output unit (12); and post-multiplexing level correction unit (14) that corrects a level deviation of the wavelength group signal after the multiplexing including the corrected subcarrier signals based on the optical level of the wavelength group signal in the output unit (12).

Methods, systems, and devices for wireless communications are described. Techniques described herein provide for a user equipment (UE) with a Modulated Retro Reflector (MRR) to support full duplex Optical Wireless Communications. To achieve full duplex communication, the UE and a network entity may use compatible modulation schemes for downlink communications and uplink communications. The UE and network entity may negotiate and agree upon compatible the uplink and downlink modulation schemes. The UE may receive a downlink OWC transmission using the downlink modulation scheme and transmit an uplink OWC transmission via modulating the downlink transmission in accordance with the uplink modulation scheme.

In an example, a method may include obtaining anomaly characteristics associated with an anomaly in a transmission medium in an optical transmission system. The anomaly may cause a degradation in one or more signal characteristics of an optical signal traversing the transmission medium. Based on the anomaly characteristics, the method may also include adjusting a first output power of a first optical amplifier that may be disposed at an input end of the transmission medium. Alternatively, or additionally, based on the anomaly characteristics, the method may also include adjusting a second output power of a second optical amplifier that may be disposed at an output end of the transmission medium.

An optical amplifier repeater system includes an optical fiber propagating a light beam in a plurality of propagation modes and an optical amplifier repeater amplifying the light beam propagated through the optical fiber. The optical amplifier repeater includes an optical demultiplexer demultiplexing the light beam in the plurality of propagation modes propagated through the optical fiber into a plurality of single-mode light beams, an optical amplifier amplifying, by simultaneous pumping, intensities of the plurality of single-mode light beams using a light beam generated by one pumping light source, an optical multiplexer multiplexing the plurality of single-mode light beams amplified by the optical amplifier into a light beam in the plurality of propagation modes, and an optical intensity adjusting unit adjusting the intensity of each of the plurality of single-mode light beams at least one of before or after the amplification by the optical amplifier. The optical intensity adjusting unit performs the adjustment by amplifying or attenuating the optical intensity of each of the plurality of single-mode light beams in an individual optical path through which the single-mode light beam is propagated.