Disclosed are embodiments of an apparatus and method relating to an optical signal to noise ratio detection circuit, adopting an optical switch, a tunable optical filter, a photoelectric conversion module, a pilot-tone modulation signal conditioning module and a control module. After the photoelectric conversion module converts a to-be-detected optical signal to a voltage signal, the pilot-tone modulation signal conditioning module respectively amplifies an AC signal and a DC signal in the voltage signal, correspondingly converts the AC signal and the DC signal to two-way digital signals, determines a modulation depth of the pilot-tone modulation signal and a modulation depth of an ASE noise according to the two-way digital signals, and calculates an optical signal to noise ratio of the optical signal.

An optical transmission system (10) includes a plurality of transmission devices such as transponders (TPs) and optical cross-connects (OXCs) installed in each of stations (11-15) connected via a communication network, a control device (20), and a substitute OXC (502) serving as a substitute transmission device. The control device 20 is installed in a control station (14) of the stations. The control device (20) controls the transmission devices of the stations (11-15) in a centralized manner in accordance with physical network (NW) configuration information (20D) stored in a DB (21) and including config information. When a transmission device is replaced with a new OXC (5o3) serving as a new transmission device, the substitute OXC (5o2) operates as a substitute for the new OXC (5o3) to communicate with the control device (20) until config setting necessary for the new OXC (5o3) is completed.

An apparatus for optical link fault management includes a processor in a network device with an optical adapter of an optical link, and a memory that stores program code. The program code is executable by the processor to store state parameters from the optical adapter in a data log, input the state parameters from the data log into a failure prediction model, and generate, using the failure prediction model, a probability of failure of the optical adapter based on current state parameters from the data log. In response to the probability of failure reaching a failure threshold, the program code is executable by the processor to decrease data traffic in the optical link and to send an alert comprising the probability of failure. The failure threshold includes a probability of failure indicative of impending failure of the optical adapter.

Systems and methods for characterizing an optical fiber performed in part by an optical node (12) in an optical line system (10) include performing one or more measurements to characterize the optical fiber (16, 18) with one or more components (50, 52) at the optical node (12), wherein the one or more components (50, 52) perform functions during operation of the optical node (12) and are reconfigured to perform the one or measurements independent of the functions; and configuring the optical node (12) for communication over the optical fiber (16, 18) based on the one or more measurements. The one or more components can include any of an Optical Service Channel (OSC), an Optical Time Domain Reflectometer (OTDR), and an optical amplifier. The configuring can include setting a launch power into the optical fiber based on the one or more measurements.

A method for monitoring a passive optical network, the passive optical network comprising a plurality of network components, comprises receiving an alert message (200) from a fault detection system associated with the passive optical network, the alert message comprising an indication of one or more candidate locations for a detected fault in the passive optical network. The method further comprises accessing an inventory (202) of the plurality of network components, the inventory storing, for each of the plurality of network components, information comprising the network component location. The method further comprises identifying (204), based on the one or more candidate locations and the network component locations, one or more network components of the plurality of network components as candidates for the cause of the detected fault.

To appropriately monitor a transmission device in an optical transmission system. A monitoring apparatus 1 monitors a plurality of transmission devices 2 having different specifications. The monitoring apparatus 1 includes a monitoring unit 11 that monitors whether a failure occurrence or failure recovery is present in the plurality of transmission devices 2, an analyzing unit 12 that determines whether the failure occurrence or the failure recovery continues for a predetermined period, in a case where the failure occurrence or the failure recovery is present in the plurality of transmission devices 2, a control unit 13 that identifies a cause of the failure, using a plurality of pieces of warning information received from the plurality of transmission devices 2 only in a case where the failure occurrence continues for the predetermined period, and a notifying unit 14 that notifies a higher-level monitoring apparatus of warning information corresponding to the cause of the failure.

An apparatus and a method for optically linking at least two AC and DC low voltage cascading power grids connecting at least two intelligent support boxes (ISB) each powered by two distinct AC standard power grid and separately powered by DC low voltage power grid with each grid is further linked by a cascading segments of optical cable grid, enabling two way control, operate and report electrical activity through plug in wiring devices (PWD) for supporting DC and AC plurality of connected/attached loads.

A system for troubleshooting signals in a cellular communications network, and in particular, for determining the cause of distortion or corruption of such signals, includes a robotic or other type of switch. The robotic switch can tap into selected uplink fiber-optic lines and selected downlink fiber-optic lines between radio equipment and radio equipment controllers in a wireless (e.g., cellular) network to extract therefrom the I and Q data. The selected I and Q data, in an optical form, is provided to an optical-to-electrical converter forming part of the system. The system includes an FPGA (Field Programmable Gate Array) or the like, and an analytic computer unit, or web server, and SSD (Solid State Drive) and magnetic disk storage, among other components of the system. The system analyzes the I and Q data provided to it, and determines the cause, or at least narrows the field of possible causes, of impairment to transmitted signals. The system includes a display which provides the troubleshooting information thereon for a user of the system to review, or other form of a report, and may communicate the analytical findings to a remote location over a public or private internet protocol network.

An apparatus includes a reconfigurable optical add/drop multiplexer (ROADM) having an input port to receive a first optical signal from a second device. The ROADM also includes a first wavelength selective switch (WSS), in optical communication with the input port, to convert the first optical signal into a second optical signal, a loopback, in optical communication with the first WSS, to transmit the second optical signal, and a second WSS, in optical communication with the loopback, to convert the second optical signal to a third optical signal and direct the third optical signal back to the second device via the input port.

Devices, computer-readable media and methods are disclosed for determining reachability for a wavelength connection in a telecommunication network. For example, a processor deployed in a telecommunication network may calculate a fiber loss on a link in the telecommunication network using optical power measurements and determine that a destination node of a wavelength connection is not reachable via a path that includes the link based upon the fiber loss of the link that is calculated. In one example, the determining is based upon a number of links in the path, an effective fiber loss for each link in the path, a penalty for nodes in the path, and an acceptable loss value. The processor may further perform a remedial action in response to determining that the destination node of the wavelength connection is not reachable via the path.