Abstract: The technology may be utilized in network environments that use fiber optic cables to connect components. Components of the network perform functions as transceivers that transmit and receive light signals via the fiber cable. When optic power data received from the transceivers is recognized as a fault, an event is identified. The system logs each received event and converts all measurements into a common unit of measurement. The system analyzes aggregated data from the transceivers to detect patterns and trends, monitor the received data and provide real time fault predictions. For example, a machine learning process may recognize subtle trends or patterns in the data, and use the recognition to predict potential failures. The system uses the received data to create a graphical user interface (“GUI”) that represents the health of the network.

Abstract: The present disclosure provides a method and system for configuring an optical time domain reflectometer (OTDR) in a gigabit passive optical networks (PON), characterized by the steps of: collecting network data of the network to be scanned by switch controller to characterize said network; collecting data from various optical network terminals (ONTs) of the gigabit passive optical networks (GPON) by an OTDR and the Switch Controller to form a training database, the training data is used to train the method; optimizing the parameters of the optical time domain reflectometer (OTDR) based on the network data and the training database by a processor provided on the switching controller using machine learning. For point-to-multipoint (PMP) networks such as PON, the present method and system provides optimal set of parameters to configure OTDR before performing trace.

Abstract: A fail-safe wireless power transmission system having a transmitter, a receiver, a receiver functionality monitor unit, a transmitter functionality monitor unit and at least two sensors. The transmitter has at least one low emission state, and at least one high emission state, the high emission states having higher emissions and more complex safety systems. The transmitter may be precluded from switching from a low emission state to any high emission states upon detection of a receiver control unit malfunction, a transmitter control unit malfunction, a likelihood of human-accessible emission from the system greater than a predetermined level, or an inconsistency between results arising from at least two of the sensors. Two different methods of such preclusion may be used simultaneously or consecutively to improve reliability. A transmitter control unit analyzes data from the sensors, and performs calculations to determine if and what type of preclusion is needed.

Abstract: The operability of path management performed in units of apparatuses subdivided by disaggregation is improved. A path display apparatus 1 which displays a path configured for a plurality of optical network apparatuses subdivided by disaggregation includes a storage unit 10 that stores configuration information 11 indicating a section of each of the optical network apparatuses; a grouping unit 21 that identifies a high-speed port of a route apparatus (DIR: Direction) which is the optical network apparatus, and determines a first group to which optical network apparatuses divided by the identified high-speed port belong, based on the configuration information 11; and a display control unit 22 that displays, on a screen, a symbol of each of the optical network apparatuses, a symbol of the section, and a symbol of the first group.

Abstract: A customer premises device including an optical modem including at least one upstream laser is power controlled to provide one or more reduced power levels of service in response to a detected AC input power failure, and/or in response to control commands, e.g., from an optical line terminal (OLT). The commands control the customer premises device to switch to a reduced power consumption mode of operation. During the reduced power mode one or a few lasers are powered, e.g., on an intermittent but predictable basis. During normal operation mode each of the upstream lasers are powered. One or more receiver circuits are also powered off during reduced power mode operation in some embodiments. A schedule is used in some embodiments to control when one or more upstream lasers and/or receivers are powered. In some embodiments the schedule is determined based on information provided by the OLT.

Abstract: Methods of operating an optical communication system in coherent optical transmissions for metro applications. Relative to conventional solutions, the optical communication system can be implemented with reduced cost and can operate with reduced power consumption, while maintaining high data rate performance (e.g., 100G). Furthermore, a programmable transceiver enables compatibility with a range of different types of optical networks having varying performance and power tradeoffs. In one embodiment, the optical communication system uses 100 Gb/s dual-polarization 16-point quadrature amplitude modulation (DP-16QAM) with non-linear pre-compensation of Indium Phosphide (InP) optics for low power consumption.

Abstract: A method and apparatus for an adaptive Hypertext Transfer Protocol (HTTP) streaming service using metadata of media content are provided. The media content may include a sequence of one or more periods. Each of the periods may include one or more representations. The metadata may include information used to describe a relationship between the representations, and include information for terminals having different display bit depth.

Abstract: A passive wavelength division mobile fronthaul network system includes a central office end, a remote end, a trunk optical fiber; a first transport unit, configured to transport, on one end of the trunk optical fiber, detection light to the trunk optical fiber; a second transport unit, configured to transport, on the other end of the trunk optical fiber, the detection light from the trunk optical fiber to each branch of the remote end; and a reflector, deployed on an end of each branch of the remote end for reflecting the detection light. The first transport unit combines the detection light to the trunk optical fiber, the second transport unit transmits, on the remote end, the detection light from the trunk optical fiber to each branch of the remote end, and finally, the reflector returns the detection light along the original path.

Abstract: The present disclosure is directed to methods and apparatus for locating luminaires within a lighting system where multiple luminaires are located on a grid of DC power rails. The AC signal generator connects to each DC power rail and transmits an AC signal along each DC power rail in turn to luminaires that each compute their distance from the generator based upon the AC signal. The AC signal generator may similarly transmit and receive data communications with luminaires across DC power rails.

Abstract: One or more operational parameters associated with pluggable optical transceivers are estimated to mitigate impairments to an optical signal caused by imperfections in the optical transceivers. A monitoring algorithm within a receiver signal processor may further use the estimated operational parameters associated with the pluggable optical transceivers to determine whether the transceivers are performing correctly. If the monitoring algorithm determines that either the transmitting or receiving optical transceiver is not functioning correctly, it may generate an alarm signal to notify a system administrator about the damaged device.

Abstract: One or more operational parameters associated with pluggable optical transceivers are estimated to mitigate impairments to an optical signal caused by imperfections in the optical transceivers. A monitoring algorithm within a receiver signal processor may further use the estimated operational parameters associated with the pluggable optical transceivers to determine whether the transceivers are performing correctly. If the monitoring algorithm determines that either the transmitting or receiving optical transceiver is not functioning correctly, it may generate an alarm signal to notify a system administrator about the damaged device.

Abstract: A Passive Optical Network, PON, comprising an Optical Line Termination, OLT, connected to one or more Optical Network Terminals, ONT, over an Optical Distribution Network, ODN, is monitored by a monitoring device. The monitoring device comprises an Optical Frequency Domain Reflectometer, OFDR, and is arranged to monitor the optical power received by the OLT and the ONTs of the PON, and to perform transceiver analysis of the OLT and the ONTs, combined with an OFDR analysis of the ODN, based on the monitored optical power violating a threshold.

Abstract: It is disclosed a remote node connectable to multiple feeder fibers from one or more central offices, COs, of a wavelength division multiplexing-based passive optical network, WDM-based PON. The remote node comprises one or more splitters each configured to receive a monitoring signal on a connected feeder fiber and to split the monitoring signal into split monitoring signals, wherein the monitoring signal uses one wavelength at a time out of a group of different wavelengths, and an arrayed waveguide grating, AWG, with output ports connectable to drop fibers. The AWG is configured to route the split monitoring signals to output ports of said AWG based on a currently used wavelength of said group of different wavelengths, for supervising drop fibers connected to the output ports. Also, a method for a remote node in the WDM-based PON, of routing a monitoring signal, is disclosed.

Abstract: An optical wavelength path rearranging method includes detecting time that elapses since a setting of optical wavelength paths in an optical wavelength division multiplexing network; and moving to a predetermined long-period optical wavelength range, an optical wavelength path that is among the optical wavelength paths and for which the detected elapsed time is long, where the optical wavelength path rearranging method is executed by a processor.

Abstract: A system and method for performing an in-service optical time domain reflectometry test, an in-service insertion loss test, and an in-service optical frequency domain reflectometry test using a same wavelength as the network communications for point-to-point or point-to-multipoint optical fiber networks while maintaining continuity of network communications are disclosed.

Abstract: Implementations of techniques and systems are disclosed for detecting a fiber fault in a point-to-point optical access network based on optical time domain reflectometry (“OTDR”) measurements. The techniques include identifying loss of service between a central office (“CO”) and a given optical network unit (“ONU”) of a plurality of ONUs. In response to the identifying the loss of service, configuring a test signal distribution unit to optically couple an OTDR unit to a selected subset of the point-to-point fiber links which includes the given ONU. An optical test signal is launched from the OTDR unit into the selected subset of the point-to-point fiber links via the test signal distribution unit. Test signal reflections are received from each of the point-to-point fiber links within the selected subset as a reflection signature, which is analyzed to identify a location of the fiber fault.

Abstract: Methods and apparatus for a network element or server end station to determine an estimated physical location of a fault in a communications link utilized by two network elements. In an embodiment, the first and second network elements generate link failure indications including time values representing when the respective network element detected the fault. In other embodiments, the link failure indications include time values transmitted over the communications link between the first and second network elements. A time distance between these time values is calculated, which is used to calculate the estimated physical location of the fault. In some embodiments, the link failure indications include sequence numbers transmitted or about to be transmitted over the communications link between the network elements. Sequence distances are calculated between the sequence numbers, and are used to calculate the estimated physical location of the fault.

Abstract: Disclosed is an apparatus for monitoring failure positions on fibers in a WDM-PON system and a WDM-PON system having the apparatus.

Abstract: Systems, methods, and devices are disclosed for monitoring optical communications between a managed location and a remote location. In particular, an optical signal is transmitted over an optical fiber and passed-through a test device. A portion of the optical signal is filtered from the original optical signal and passed to a monitoring unit. The monitoring unit may instruct one or more switches in the test device to loop the optical signal back toward the managed location. Subsequently, testing and monitoring may be performed at the managed location. The device may provide a test output or may transmit the information to the managed location.

Abstract: Novel tools and techniques that can be used to detect network impairment, including but not limited to impairment of optical fiber networks. In an aspect, such tools and techniques can be deployed at relatively low cost, allowing pervasive deployment throughout a network. In another aspect, such tools and techniques can take advantage of a “dying gasp,” in which a network element detects a sudden drop in received optical (or electrical) power, resolution, etc. at short time scales and sends a notification across the network before the connection is completely compromised. In yet another aspect, some tools can include a supervisory function to analyze aspects of the dying gasp with the goal to determine network segments associated with an impairment and an estimate of the location of an impairment within the network.

Abstract: The invention discloses a system, a method and an apparatus for optical network protection. The system includes: an output control apparatus for obtaining protection mode information configured by a system and controlling an input signal to be output from a set line corresponding to said protection mode information; and a detection control apparatus for detecting powers of signals transmitted on an active line and on a standby line, if it is determined that the active line is abnormal and the standby line is normal according to detection results, then controlling the input signal to be output from a protection line corresponding to the protection mode information; if it is determined that the active line is normal, or that the active line and the standby line are abnormal according to the detection result, then controlling the input signal to be output from a set line corresponding to the protection mode information.

Abstract: Methods and apparatus for a network element or server end station to determine an estimated physical location of a fault in a communications link utilized by two network elements. In an embodiment, the first and second network elements generate link failure indications including time values representing when the respective network element detected the fault. In other embodiments, the link failure indications include time values transmitted over the communications link between the first and second network elements. A time distance between these time values is calculated, which is used to calculate the estimated physical location of the fault. In some embodiments, the link failure indications include sequence numbers transmitted or about to be transmitted over the communications link between the network elements. Sequence distances are calculated between the sequence numbers, and are used to calculate the estimated physical location of the fault.

Abstract: An optical transmission system includes a first node and a second node, the first node includes a first optical amplifier which outputs a signal to the second node through a first transmission line and a first monitoring unit, the second node includes a monitor which monitors a signal from the first transmission line, a second optical amplifier which outputs a signal to the first node through a second transmission line and a second monitoring unit, upon detecting disconnection from the first transmission line, the second monitoring unit transmits a notification for making power of the first optical amplifier reduced, upon receipt of the notification, the first monitoring unit reduces power of the first optical amplifier, and transmits a completion notification to the second monitoring unit, and upon not receiving the completion notification even after expiration of an allowed time, the second monitoring unit reduces power of the second optical amplifier.

Abstract: Novel tools and techniques that can be used to detect network impairment, including but not limited to impairment of optical fiber networks. In an aspect, such tools and techniques can be deployed at relatively low cost, allowing pervasive deployment throughout a network. In another aspect, such tools and techniques can take advantage of a “dying gasp,” in which a network element detects a sudden drop in received optical (or electrical) power, resolution, etc. at short time scales and sends a notification across the network before the connection is completely compromised. In yet another aspect, some tools can include a supervisory function to analyze aspects of the dying gasp with the goal to determine network segments associated with an impairment and an estimate of the location of an impairment within the network.

Abstract: A system for measuring a length of one or more spans between a first optical transceiver and a second optical transceiver in a fiber-optic network, which can determine, at a processor associated with the first optical transceiver, a round-trip time of an optical signal communicated from the first optical transceiver to the second optical transceiver and back to the first optical transceiver. The system can also determine, at the processor, a half-round-trip time by dividing the round-trip time by two. The system can also determine, at the processor, a distance between the first and the second optical transceivers by multiplying the speed of light by the half-round-trip time.

Abstract: A signal is conducted from a controller module onto a network via a first coupling. The signal is transmitted across the network and received at one or more receiver modules via one or more second couplings. At the one or more receiver modules, the received signal is analyzed and based upon the analysis, a determination is made as to whether a fault has occurred in the network and/or where the occurrence occurred.

Abstract: Provided is a waveform reconstruction device capable of easily reconstructing an accurate time waveform of an optical signal without using an ultrafast time gate or a reference light source.

Abstract: An apparatus and method for deriving fiber characteristics between two nodes in an optical communication network are disclosed. A roundtrip time for a signal to travel between two nodes is measured by sending the signal via the optical supervisory channel from a first node to a second node, which is configured for loopback operation. Fiber characteristics can be calculated based on the measured roundtrip time.

Abstract: A system and method is disclosed that allows for the monitoring, analyzing and reporting on performance, availability and quality of optical network paths. The correlation of PM parameter metrics to client connections, coupled with threshold-based alarm generation provides a proactive and predictive management, reporting and analyzing of the health and effectiveness of individual path connections to alert Operational Support (OS) staff and/or customers to signal degradation and impending Network Element (NE) failures. The system and method performs in real-time processing intervals required for alarm surveillance in a telecommunications network.

Abstract: A method and a device for monitoring a cable system in the field of communications are provided. An optical signal emitted by an optical source to a transmission link of the cable system is divided into two paths of optical signals, in which one path of optical signals serve as local coherent light, and the other path of optical signals are transformed by multipath frequency shift to multiple paths of detection optical signals of different frequencies. A monitoring result is obtained by performing coherent detection, with the local coherent light, on the returned optical signals of the multiple paths of detection optical signals of different frequencies. The device includes an optical source, a multipath frequency shift module, and a coherency module.

Abstract: The present invention relates to the field of communication transmission, and in particular, to a method for generating a probe pulse and a coherent optical time domain reflectometer. The coherent optical time domain reflectometer includes: a control unit, configured to generate a first pulse signal and a second pulse signal which have a same period T, where the second pulse signal lags behind the first pulse signal, and T satisfies T?t+2L/C; a driving unit, configured to generate a frequency change driving signal according to the first pulse signal; a continuous light laser device, configured to generate, as driven by the frequency change driving signal, continuous light having a changing frequency and an unchanging frequency spectrum width; and a probe pulse generating unit, configured to modulate the continuous light according to the second pulse signal to generate a probe pulse.

Abstract: A method includes generating a test signal and modulating the test signal. The method may also include transmitting the test signal on an optical path, where the optical path may include a number of add-drop multiplexer devices and amplifiers. The method may also include receiving the test signal at a destination device and converting the received test signal into an electrical signal. The method may further include identifying a portion of the electrical signal that is associated with the modulated test signal.

Abstract: A method for allocating faults in a passive optical network (PON) by placing a number of passive unique optical correlators in a number of respective diagnostic points of the PON, each of the passive unique optical correlators being responsive to an optical diagnostic signal by returning a predetermined unique matching signal; by further transmitting the diagnostic optical signal in the PON towards the diagnostic points to receive upstream response signals from the correlators. Upon detecting presence or absence, in the received response signals, of a predetermined unique matching signal expected from a specific optical correlator, judging about a fault in proximity of the respective specific diagnostic point.

Abstract: Methods and apparatuses for enabling supervision of fibres in an optical communication network, where a Central Office provides data signals to a Remote Node for distribution to Optical Network Terminals ONTs. The Central Office generates and sends test signals of different monitoring wavelengths associated to predefined groups of said ONTs, to the Remote Node. The Remote Node routes each test signal to a corresponding associated group of ONTs according to the wavelength of the test signal. When receiving a back-scattered and back-reflected test signal caused by a faulty optical fibre, the Central Office is able to identify the faulty optical fibre based on the wavelength of the back-scattered and back-reflected signal.

Abstract: A method includes applying pulsed light to a first end of an optical fiber from an optical fault locator during a first distance test. The method includes determining an estimated distance to a fault based on the pulsed light. The method includes sending information indicative of the estimated distance to a remote device. The method also includes applying first visible light from the optical fault locator to the first end of the optical fiber to facilitate identification of the fault at a first site that is remote from the first end of the optical fiber.

Abstract: An apparatus comprising an optical transmitter, a coarse tuner coupled to the optical transmitter and having a first tuning range, a fine tuner coupled to the optical transmitter and having a second tuning range smaller than and within the first tuning range, a wavelength division demultiplexer coupled to the optical transmitter and to a plurality of optical fibers, and a detector coupled to the optical transmitter and the wavelength division demultiplexer.

Abstract: The present invention discloses a Wavelength Division Multiplexing Filter which can satisfy coexistence requirements of different PON systems and an optical line detecting system.

Abstract: Fault analysis of a Passive Optical Network comprising Optical Network Terminal(s) uses Optical Time Domain Reflectometry (OTDR). An OTDR measurement signal is supplied to a multistage splitter having a ratio 2:Nroot. At least one drop link which is connected to the multistage splitter comprises one or more sub-splitters which having a ratio 1:Nbranch. A new event location is determined based on the OTDR measurement signal by analyzing OTDR measurement data relating to the sub-splitter based on distance from the multistage splitter and to the sub-splitter. A fault magnitude is calculated for a given location by subtracting an event magnitude obtained from the new OTDR measurement from a reference OTDR measurement and taking into account the number of drop links connected to the last splitter stage and to the sub-splitter in the reference measurement and the new measurement, thereby enabling determination of position and severity of the fault locations.

Abstract: A system and method for monitoring a structure and for distinguishing between an alarm condition, and a nuisance event such as rain. An optical fibre sensor (20,22) produces a signal indicative of a disturbance and level crossing rates are determined to distinguish between noise in the signal (nuisance event) and a required event. A FFT technique is also disclosed as well as classification of an event by extracting predetermined features from the signal.

Abstract: A technique for detecting a fiber fault in a WDM optical access network includes launching a test signal into a fiber trunk line linking a central office (“CO”) to a remote node (“RN”) of the WDM optical access network. The test signal is generated by an optical time domain reflectometry unit to simultaneously fault test fiber access lines linking the RN to customer premises. The test signal is separated from downstream WDM signals at the RN. The test signal is power split at the RN into a plurality of access line test signals. The access line test signals are each recombined with a corresponding one of the downstream WDM signals onto a corresponding one of the fiber access lines. Test signal reflections are received at the CO from the fiber access lines as a reflection signature and analyzed to identify a location of the fiber fault.

Abstract: Two or more optical transceivers coupled to each other by an optical link to optimize communication over the optical link. A first transceiver generates electrical data that represents an operational parameter for optimization. The transceiver then converts the electrical data into an optical signal and transmits the optical signal over the optical link to a second transceiver. The second transceiver recovers the electrical data from the optical signal and uses the recovered electrical data to change characteristics of the optical signal transmitted by the second transceiver.

Abstract: A detecting method, an apparatus, and a system in an Optical Distribution Network (ODN) are provided. The method includes: an Optical Line Termination (OLT) reserves a test window, and an Optical Network Unit (ONU) stops sending an uplink signal in the test window, the OLT emits a downlink test signal having a wavelength the same as that of the uplink signal in the test window, the OLT receives backward signals of the downlink test signal, in which the backward signals include a backward scattered signal and a backward reflected signal, processes the backward signals, and obtains state information of the ODN according to the backward signals. The method does not need to add other hardware, and the downlink signal is sent normally in the downlink. The implementation is low in the cost and easy in the technology.

Abstract: A system and method for performing an in-service optical time domain reflectometry test, an in-service insertion loss test, and an in-service optical frequency domain reflectometry test using a same wavelength as the network communications for point-to-point or point-to-multipoint optical fiber networks while maintaining continuity of network communications are disclosed.

Abstract: Disclosed herein are various embodiments of a time-domain reflectometer having a transmitter configured to apply, to a system under test (SUT), an intensity-modulated probe signal generated based on a periodic pseudo-random bit sequence. The reflectometer further has a receiver configured to receive, back from the SUT, a reflected signal corresponding to the probe signal. The receiver converts the received reflected signal into a binary bit sequence using a relatively simple slicer circuit, and without the use of complex analog circuits and/or multi-bit analog-to-digital converters. The binary bit sequence is then compared with the original pseudo-random bit sequence to obtain a measure of the impulse response of the SUT. In some embodiments, the reflectometer has a controllable noise generator that can be used, e.g., to optimize the obtained measure for the detection of multiple SUT defects having significantly differing reflection characteristics.

Abstract: Novel tools and techniques that can be used to detect network impairment, including but not limited to impairment of optical fiber networks. In an aspect, such tools and techniques can be deployed at relatively low cost, allowing pervasive deployment throughout a network. In another aspect, such tools and techniques can take advantage of a “dying gasp,” in which a network element detects a sudden drop in received optical (or electrical) power, resolution, etc. at short time scales and sends a notification across the network before the connection is completely compromised. In yet another aspect, some tools can include a supervisory function to analyze aspects of the dying gasp with the goal to determine network segments associated with an impairment and an estimate of the location of an impairment within the network.

Abstract: An apparatus comprising an optical transmitter, a coarse tuner coupled to the optical transmitter and having a first tuning range, a fine tuner coupled to the optical transmitter and having a second tuning range smaller than and within the first tuning range, a wavelength division demultiplexer coupled to the optical transmitter and to a plurality of optical fibers, and a detector coupled to the optical transmitter and the wavelength division demultiplexer. A network component comprising at least one processor configured to implement a method comprising detecting an Optical Time Domain Reflectometry (OTDR) signal spectrum that has a modulated pattern, and detecting a reflected OTDR signal spectrum that has a shifted modulated pattern comprising a frequency shift with respect to the OTDR signal spectrum and a time shift proportional to the frequency shift.

Abstract: The present invention provides a method for establishing an inter-domain path that satisfies wavelength continuity constraint. The fPCE stores a virtual topology comprised by border nodes of all domains. The present invention uses parallel inter-domain path establishment method to decrease the influence from WCC. Compared with the sequential process way in prior art, it enhanced the resource utilization and decreased computation delay.

Abstract: A network monitoring module for deployment in a branched optical network at a split location where the network splits into a plurality of branches, the network monitoring module is disclosed, comprising an array of transmitters for generating optical test signals, an output of each transmitter in the array being optically connected to a respective branch, a detector for receiving a remotely generated optical trigger signal which identifies a particular one of the transmitters, and a CMOS circuit for selectively triggering the transmitter identified in the optical trigger signal to transmit an optical test signal into the branch connected to that transmitter.

Abstract: A transmitting apparatus connected via an optical branching apparatus to an optical communication device group includes a control unit that for each periodic transmission period including a first transmission period with a test period in which the optical communication device group is not allowed to transmit optical signals and a second transmission period without the test period, allows the optical communication device group to transmit the optical signals during a period different from the test period; a test light sending unit that sends test light to the optical branching apparatus during the test period; a light receiving unit that receives optical signals transmitted from the optical communication device group, and reflected light of the sent test light; a measuring unit that measures intensity of the reflected light received at different elapsed times after the test light is sent; and an output unit that outputs information based on the measured intensity.

Abstract: A correlation system, such as a correlation optical time domain reflectometer (OTDR) system, transmits a correlation sequence, such as an M-sequence, and measures the returns of the correlation sequence over time. The system correlates the transmitted sequence with the returns to provide correlation measurement values that respectively correspond to different distances from the point of transmission. A correlation error compensation element estimates a correlation error floor based on at least one correlation measurement value corresponding to a point along the fiber beyond a finite impulse response (FIR) length from the transmitter. The correlation error compensation element adjusts each correlation measurement value estimate in order to cancel the contribution of the correlation error floor from the measurements to provide compensated measurement values that are substantially free of the effects of the correlation error floor.