A polarimeter system integrated into an optical line system includes a transmitter coupled to a transmit filter communicatively coupled to an output port in an optical line device, wherein the transmitter is configured to generate a polarization probe signal, and wherein a wavelength of the polarization probe signal is configured to operate in-service with traffic-bearing channels on the output port; and a polarimeter receiver coupled to a receive filter communicatively coupled to an input port in the optical line device, wherein the polarimeter receiver is configured to vary arrangement of input light from the filter and to measure various outputs of the varied arrangement to derive measurement of State of Polarization (SOP) of the input light.

An object is to provide a monitoring device capable of acquiring ONU-specific information and connection information even in the case of an optical communication system with the MC system, and enabling optical fiber cable switching work to be finished in a short time. The monitoring device according to the present invention is a monitoring device that monitors an optical communication system in which an OLT and an ONU are connected by a communication optical fiber, and includes: an optical receiver for receiving a signal beam transmitted by the ONU from the communication optical fiber; and an OAM frame analysis unit for extracting, from the signal beam received by the optical receiver, an OAM frame at a MEG level at which the ONU and the OLT are set as monitoring end points, and acquiring a transmission source address and a MEG-ID that identifies a MEG in the OAM frame.

A synchronizer for synchronizing transfer over an optical link includes a frequency reference oscillator; a tracking optical timing source; a tracking comb signal; a signal processor-controller; a comb timing discriminator; a clock frequency comb; a bidirectional terminal; a time-frequency offset measurement system; and a second comb timing discriminator.

A spatial mode multiplexer for multiplexing optical signals onto different spatial modes includes an optical path for directing a probe signal through a mode converter of the multiplexer. A spatial profile of an optical phase of the probe signal is detected e.g. by splitting the reference signal into monitoring and reference paths to produce an interference pattern that can be captured and processed to control the spatial mode converters.

There is provided a control device for controlling a first transmission device and a second transmission device, the control device including a memory, and a processor coupled to the memory and the processor configured to set a first wavelength path between the first transmission device and the second transmission device, select a monitoring wavelength path from established wavelength paths allocated on a transmission line between the first transmission device and the second transmission device, monitor a signal quality of the monitoring wavelength path, and increase power of the first wavelength path, based on the signal quality of the monitoring wavelength path.

Disclosed are a function split structure for a mobile convergence optical transmission network and a method of providing coordinated multi-point technology using the same. The mobile convergence optical transmission network may include a centralized unit (CU), a distributed unit (DU) connected to the CU, a transport node (TN) of an optical transmission network connected to the DU via a first interface, an aggregated unit (AU) connected to a transport unit (TU) of the optical transmission network via the first interface, and a radio unit (RU) connected to the AU via a second interface corresponding to a split structure for a lower layer than the first interface.

A method is provided for determining an optical signal to noise ratio of a dual polarization optical signal. The method includes: detecting, in the dual polarization optical signal, a modulation signal which modulates, at at least one low amplitude level that is approximately zero and at a high amplitude level, the dual polarization optical signal, and determining the optical signal to noise ratio from a measurement of the power of the modulation signal.

An apparatus and method for providing a differential latency, DL, between an upstream, US, transmission and a downstream, DS, transmission via an optical transmission link (OTL), said apparatus comprising a measurement unit (2) configured to measure the round trip delays, RTD, of at least two measurement signals having different measurement wavelengths; and a processing unit (3) configured to derive an upstream, US, delay of at least one optical signal at an upstream wavelength from the at least two measured round trip delays, RTD, and to derive a downstream, DS, delay of at least one optical signal at a downstream wavelength from the at least two measured round trip delays, RTD, wherein the differential latency, DL, is calculated on the basis of the derived delays, RTD.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A test and measurement instrument includes a first input port and a second input port that receive a first input signal modulated according to a first clock signal and a second input signal modulated according to a second clock signal, respectively. The first clock signal and the second clock signal may be asynchronous. The instrument also includes a phase reference that generates clock data for the second clock signal. The instrument includes a processor that determines time bases for the input signals that comprise different rates based on the received and/or generated clock data. The instrument also includes a display coupled to the processor. The display concurrently displays the first input signal in a first graticule according to the first time base and the second input signal in a second graticule according to the second time base.