Abstract: A comprehensive integrated system and method includes (i) proactively monitoring a network for degraded service and to proactively make repairs to components before service outages, (ii) identifying the root causes of hard alarms and failures on a layer 1 transport network and generate trouble tickets; and (iii) after repair, verifying that repaired backbone network meets or exceeds performance criteria of Service Level Agreements (SLAs) with customers. A method includes surveilling first equipment in a network wherein the first equipment is in a controlled portion of the network, observing a set of messages wherein the set of messages relate to second equipment in a leased portion of the network, and detecting a fault in the network based on the surveilling step or the observing step.

Abstract: An optronic transceiver module capable of implementing an optical bidirectional communication of the point to point type via at least one main optical fibre is disclosed. The optronic transceiver module includes a first optical module for supervising an uplink signal received via the main optical fibre delivering a first supervision result, a first optical module for switching the bidirectional communication via the main optical fibre to a bidirectional communication via a backup optical fibre, and vice versa, the first optical switching module being controlled by the first optical supervision module depending on the first supervision result delivered.

Abstract: An electrical layer subnetwork connection protection includes determining, by a network device including a processor, signal status information based on a power of an obtained optical signal. The signal status information is used to indicate a state of a subnetwork connection carrying the optical signal. The method also includes filtering, by the network device, the signal status information based on a preset first threshold. The first threshold indicates a minimum duration in which the optical signal is in a valid state. The method further includes determining, by the network device based on the filtered signal status information, whether to switch a currently used first clock to a second clock different from the clock. The first clock or the second clock is used to initialize connection monitoring information in response to the determination of whether to switch the currently used first clock to the second clock.

Abstract: A network design apparatus for designing a network includes a processor; and a memory storing program instructions that cause the processor to receive input of a configuration condition for a network having a communication layer and at least one computing layer, a cost condition for the network, and a demand condition representing uncertain demand for the network, perform an operation for solving an adjustable robust optimization problem in which an objective function is to minimize a sum of a fixed cost and a variable cost for a resource placed at each base in the communication layer and the computing layer, and determine a configuration of the network based on placement and capacity of a resource obtained by the performing of the operation. The demand condition includes a set of one or more bases from which the resource is assignable in response to the demand.

Abstract: A modular optical add/drop system supporting a Colorless, Directionless, and Contentionless (CDC) architecture includes a first Contentionless Wavelength Selective Switch (CWSS)-based optical add/drop device; and one or more channel pre-combiners each having a common port with a transmit port and a receiver port, at least two local add/drop ports, components configured to combine channels between the at least two local add/drop ports and the common port, and a splitter and a combiner connected to the common port, wherein a first output of the splitter and the combiner is connected to the first CWSS-based optical add/drop device. The modular optical add/drop system can further include a second CWSS-based optical add/drop device, wherein a second output of the splitter and the combiner is connected to the second CWSS-based optical add/drop device.

Abstract: Aspects of the disclosure provide for methods and systems for feedback control of mode MUX and DEMUX. An aspect of the disclosure provides for a method associated with a mode MUX. The method includes modulating each WDM signal of a first set of WDM signals with a pilot tone of different frequency. The method further includes spatially multiplexing the first set of WDM signals to generate a multi-mode signal. The method further includes detecting the pilot tones from the multi-mode signal. The method further includes tuning the mode MUX based on the detecting. Another aspect of the disclosure provides for a method associated with a mode DEMUX. The method includes spatially demultiplexing a multi-mode signal into a set of WDM signals. The method further incudes detecting pilot tones from the set of WDM signals and tuning the mode DEMUX based on the detecting.

Abstract: Embodiments of the present disclosure relate to a method and an optical communication device implemented in an optical network and a computer-readable storage medium. In the method described herein, a distribution point unit (DPU) of the optical network receives a message comprising an identification of a target backhaul model from an Optical Line Terminal (OLT) in the optical network. The received message is parsed to obtain the identification of the target backhaul model. The target backhaul model indicated by the identification is used to communicate with the OLT. In this way, the DPU is compatible with many types of backhaul models and is capable of flexibly switching between the many types of backhaul models.

Abstract: A management system for an optical line system includes one or more processors and memory storing instructions that, when executed, cause the one or more processors to receive State of Polarization (SOP) measurements from one or more optical components in the optical line system, wherein the SOP measurements are taken while traffic-bearing channels are operating, and monitor health of one or more fibers based on the SOP measurements. The health can include detection and/or localization of SOP transients.

Abstract: Embodiments relate to providing simultaneous digital and analog services in optical fiber-based distributed radio frequency (RF) antenna systems (DASs), and related components and methods. A multiplex switch unit associated with a head-end unit of a DAS can be configured to receive a plurality of analog and digital downlink signals from one or more sources, such as a service matrix unit, and to assign each downlink signal to be transmitted to one or more remote units of the DAS. In one example, when two or more downlink signals are assigned to be transmitted to the same remote unit, a wave division multiplexer/demultiplexer associated with the multiplex switch unit can be configured to wave division multiplex the component downlink signals into a combined downlink signal for remote side transmission and to demultiplex received combined uplink signals into their component uplink signals for head-end side transmission.

Abstract: A network element includes at least two Time Division Multiplexing (TDM) modules each including a TDM client interface, TDM processing circuitry, and circuit emulation circuitry; and a packet switch fabric connected to the at least two TDM modules in a Link Aggregation Group (LAG) for a protected TDM service, and configured to output a packet interface, wherein the protected TDM service is provided as a single packetized TDM stream via the packet interface from the packet switch fabric.

Abstract: A redundancy system for a distributed antenna system is provided. The system includes a first communication link, a second communication link, a first communication node and a second communication node. The first communication link traverses first path. The second communication link traverses a second path. The second path is spatially separated from the first path. The first communication node is communicatively coupled to transmit the same signal through both the first communication link and the second communication link. The second communication node has a receiver system that is communicatively coupled to receive the signals transmitted through the first and second communication links. The receiver system is configured to synchronize delay and phase differences between the received signals and then combine the signals together to generate a single output.

Abstract: The control system is a control system that controls a connection between an autonomous mobile robot and a base station, the control system including: a radio communication unit that communicates with the base station; and a connection control unit that performs control, in a connection of communication performed by the radio communication unit, when a radio wave shielding object which the autonomous mobile robot is able to pass through is on a path along which the autonomous mobile robot is to move, so that the autonomous mobile robot is prompted to connect to a predetermined base station of which a received radio wave intensity at a position on the path in front of the shielding object is affected by the shielding object.

Abstract: Path computation systems and methods are provided herein. According to one embodiment, a method includes obtaining topological information representing a topology of at least a portion of a network. The topological information includes one or more nodes and one or more links, each link configured to connect a node with a neighboring node. Each node includes a plurality of internal components and a plurality of connections configured to interconnect the internal components. The method further includes running path computation through the topological information to determine a plurality of paths from a first internal component to a second internal component. Also, the method includes applying elimination rules during the path computation to filter out one or more paths detected as being invalid. The elimination rules are based on one or more predetermined path sequences that include at least two hops involving an unviable sequence of specific types of internal components.

Abstract: A system for hot swapping a network switch without disconnecting the network switch connectors is provided. The system disaggregates the switch faceplate network cable connectors from the internal components of the network switch so that the internal switch components may be removed from the switch without disconnecting the switch network cables.

Abstract: Disclosed herein is a transponder comprising a transmitter and a receiver. The transponder further comprises a receiver input amplifier, a bypass line, and a control unit configured for determining the performance of the transponder in relation to an OSNR related parameter, by controlling the transponder to generate a noise signal to be received by the receiver. The receiver input amplifier is operated to thereby cause ASE in the receiver input amplifier to facilitate the determination. A test signal is generated at the transmitter Said noise signal and said test signal, and/or one or more respective replicas thereof, are superimposed to form a combined signal to be received by said receiver to further facilitate determination of said performance related parameter based on said combined signal, wherein for generating said combined signal, said test signal is fed from the transmitter to the receiver by means of said bypass line.

Abstract: Disclosed herein are switch devices in terminal ends of a network and methods of using same. One embodiment relates to a terminal end of a network including a terminal end transceiver configured to communicate with one or more end user devices, and a switch device configured to automatically route communication at the terminal end transceiver between a primary communication path with a central office and an auxiliary communication path with the central office. Another embodiment relates to a method of switching between primary and auxiliary communication paths at a terminal end. Automatic switching is particularly applicable in a looped communication architecture with redundant communication paths for preventing interruption and increasing reliability for an improved user experience. Another embodiment relates to indexing with splices to reduce connections in a communication path and increase signal quality.

Abstract: In order to enable an area suspected of having a communication abnormality to be identified from among a communication device and a communication path that constitute a communication system, this abnormality identification device is provided with: a first output unit which outputs first information that is information indicating the suitability of a transmission signal to be supplied to a communication channel; a second output unit which outputs second information that is information indicating the suitability of a reception signal corresponding to the transmission signal that has arrived via the communication channel; and a third output unit which outputs third information that is information indicating the suitability of a signal obtained by applying predetermined processing to the reception signal.

Abstract: An example system includes a first network node, a second network node, and a third network node. The first network node is configured to generate a first optical subcarrier representing first data, and transmit the first optical subcarrier to the second network node. The second network node is configured to receive the first optical subcarrier from the first network node, generate a second optical subcarrier representing the first data, where the second optical subcarrier is different from the first optical subcarrier, and transmit the second optical subcarrier to the third network node.

Abstract: Techniques for determining an alternative communication mode for vehicle-to-vehicle communication at a host vehicle can include monitoring the primary mode of RF communication to ensure it is effectively communicating and, if not, intelligently selecting a backup communication mode comprising one or more other sensors and/or systems of the vehicle. The selection of the backup communication mode may take into account various factors that can affect the various modes of communication from which the backup communication mode is selected.

Abstract: Systems and methods for integrated band splitter for scaling a dual band Reconfigurable Optical Add/Drop Multiplexer (ROADM). A degree in a ROADM includes ROADM components including a line port and a plurality of connection ports; channel multiplexer/demultiplexer components including degree ports and local add/drop ports; and one or more band splitters in between the ROADM components and the channel multiplexer/demultiplexer components. The band splitter can be configured to split/combine C-band spectrum and L-band spectrum. The band splitter can be a passive fiber device.

Abstract: A first network device may configure a first bridge connecting a passive optical network (PON) controller and first optical line terminals (OLTs) of the first network device. The first network device may be associated with a PON and each of the first OLTs may be connected to a first plurality of optical network units (ONUs). The first network device may establish a connection between the first bridge and a second bridge of a second network device. The second network device is associated with the PON, the second bridge may connect with second OLTs of the second network device, and each of the second OLTs may connect to a second plurality of ONUs. The PON controller of first network device may receive traffic from a PON domain manager and may provide the traffic to the first OLTs and the first plurality of ONUs via the first bridge.

Abstract: A laser light generator is configured to generate one or more wavelengths of continuous wave laser light. The laser light generator is configured to collectively and simultaneously transmit each of the wavelengths of continuous wave laser light through an optical output of the laser light generator as a laser light supply. An optical fiber is connected to receive the laser light supply from the optical output of the laser light generator. An optical distribution network has an optical input connected to receive the laser light supply from the optical fiber. The optical distribution network is configured to transmit the laser light supply to each of one or more optical transceivers and/or optical sensors. The laser light generator is physically separate from each of the one or more optical transceivers and/or optical sensors.

Abstract: Embodiments relate to providing simultaneous digital and analog services in optical fiber-based distributed radio frequency (RF) antenna systems (DASs), and related components and methods. A multiplex switch unit associated with a head-end unit of a DAS can be configured to receive a plurality of analog and digital downlink signals from one or more sources, such as a service matrix unit, and to assign each downlink signal to be transmitted to one or more remote units of the DAS. In one example, when two or more downlink signals are assigned to be transmitted to the same remote unit, a wave division multiplexer/demultiplexer associated with the multiplex switch unit can be configured to wave division multiplex the component downlink signals into a combined downlink signal for remote side transmission and to demultiplex received combined uplink signals into their component uplink signals for head-end side transmission.

Abstract: A comprehensive integrated system and method includes (i) proactively monitoring a network for degraded service and to proactively make repairs to components before service outages, (ii) identifying the root causes of hard alarms and failures on a layer 1 transport network and generate trouble tickets; and (iii) after repair, verifying that repaired backbone network meets or exceeds performance criteria of Service Level Agreements (SLAs) with customers. A method includes surveilling first equipment in a network wherein the first equipment is in a controlled portion of the network, observing a set of messages wherein the set of messages relate to second equipment in a leased portion of the network, and detecting a fault in the network based on the surveilling step or the observing step.

Abstract: The present disclosure provides a packet tracing mechanism will be described that provides packet tracing information to a mobile network controller. In one aspect, a method includes receiving a data packet sent from a source node to a destination node; determining if the data packet is to be updated with packet tracing information; and upon determining that the data packet is to be updated, updating the packet tracing information of the data packet to include identification of the network device and an ingress timestamp of the data packet at the network device for a corresponding network controller to determining network routing policies.

Abstract: An optical network control device includes: a path setting unit that sets, based on topology information including a connection relationship among a plurality of nodes and a first route selection index value of routes each connecting the plurality of nodes, a first path for a route having the first route selection index value being minimum from among route candidates linking a start point node and an end point node of a requested traffic; a topology information modification unit that calculates a second route selection index value acquired by increasing the first route selection index value of the route that accommodates the first path; and a path selection unit that selects a second path for a route having the second route selection index value being minimum from among the route candidates.

Abstract: The present application provides a method and a user device for monitoring a use condition. The method includes determining a baseline level of performance for each of one or more elements of the device including a determined replacement threshold level. The method further includes running a diagnostic determining the current performance of at least some of the one or more elements for which a baseline level of performance has been determined, wherein the running of the diagnostic includes a diagnostic determination triggered by a detected non-standard use condition. The current performance of the at least some of the one or more elements is compared to the determined baseline level performance for the respective ones of the one or more elements of the user device. When the determined current performance of at least one of the one or more elements falls below the determined replacement threshold level, the user is notified of a need for service of the user device.

Abstract: Process margin relaxation is provided in relation to a compensated-for process via a first optical device, fabricated to satisfy an operational specification when a compensated-for process is within a first tolerance range; a second optical device, fabricated to satisfy the operational specification when the compensated-for process is within second tolerance range, different than the first tolerance range; a first optical switch connected to an input and configured to output an optical signal received from the input to one of the first optical device and the second optical device; and a second optical switch configured to combine outputs from the first optical device and the second optical device.

Abstract: Embodiments disclosed herein provide a hybrid fiber-copper access network in which a main OLT sends data to the DSLAMs via a plurality of point-to-point optical fiber connections. A standby OLT is provided which has a plurality of point-to-multi-point optical fiber connections to the DSLAMs. In the event of a failure, data can be sent to some of the DSLAMs via the standby OLT and the point-to-multi-point optical fiber connections. Following the rectification of the fault, the network can revert to its normal state and transmit data to the DSLAMs via the main OLT and the plurality of point-to-point optical fiber connections.

Abstract: Techniques for determining an alternative communication mode for vehicle-to-vehicle communication at a host vehicle can include monitoring the primary mode of RF communication to ensure it is effectively communicating and, if not, intelligently selecting a backup communication mode comprising one or more other sensors and/or systems of the vehicle. The selection of the backup communication mode may take into account various factors that can affect the various modes of communication from which the backup communication mode is selected.

Abstract: Some aspects and embodiments of the present invention provide effective mechanisms for provisioning virtual networks on communication networks. In particular some aspects and embodiments provide an effective mechanism for embedding a virtual network into a multi-layered substrate network which utilizes a different communication technology at each layer. One such example is an IP network overlaid over an optical network, such as an OTN network. Embodiments jointly determine the assignment of virtual nodes and virtual links. Assigning the nodes and links together can provide for a more optimal solution than assigning the nodes and the links separately. Some embodiments generate a collapsed graph which includes the optical network and the IP network in a single layer. Accordingly some embodiments jointly determine the assignment of virtual nodes and virtual links within such a collapsed graph, which can provide more optimal assignments than considering assignments within each layer separately.

Abstract: Embodiments relate to providing simultaneous digital and analog services in optical fiber-based distributed radio frequency (RF) antenna systems (DASs), and related components and methods. A multiplex switch unit associated with a head-end unit of a DAS can be configured to receive a plurality of analog and digital downlink signals from one or more sources, such as a service matrix unit, and to assign each downlink signal to be transmitted to one or more remote units of the DAS. In one example, when two or more downlink signals are assigned to be transmitted to the same remote unit, a wave division multiplexer/demultiplexer associated with the multiplex switch unit can be configured to wave division multiplex the component downlink signals into a combined downlink signal for remote side transmission and to demultiplex received combined uplink signals into their component uplink signals for head-end side transmission.

Abstract: An indication of a combination of a Shared Risk Link Group identifier and a node identifier for each of a plurality of links through at least one network and between a source network device and a destination network device is received at a network device. A primary path through the at least one network between the source network device and the destination network device is determined at the network device. The primary path comprises a first subset of the plurality of links through the at least one network. A back-up path through the at least one network between the source network device and the destination network device is determined at the network device. The back-up path comprises a second subset of the plurality of links through the at least one network.

Abstract: There is provided a reception device including a receiver configured to receive a wavelength-multiplexed optical signal so as to generate a wavelength-multiplexed signal, a filter configured to pass through the wavelength-multiplexed signal having a specific wavelength and an adjacent wavelength to the specific wavelength from the wavelength-multiplexed signal, and a processor configured to detect a specific signal having the specific wavelength from the wavelength-multiplexed signal having the passed through wavelengths by the filter, and detect a first supervisory control signal having the specific wavelength and a second supervisory control signal having the adjacent wavelength from the wavelength-multiplexed signal having the passed through wavelengths by the filter.

Abstract: In the case of a OXC device having a route & select-type configuration of the conventional technique, when the port number is 20, then the entire device requires 120 WSSs having a 1×9 configuration. In the case of a route & select-type OXC device having ports more than 20 ports, a large amount of expensive WSSs is required. Thus, such a device is impractical from the viewpoint of cost. Thus, the expansion depending on an increase of traffic at nodes was impossible, flexible scalability could not be provided, and a reasonable network operation from the viewpoint of economy was difficult. According to the OXC device of this disclosure, regardless of the input port number and the output port number of the device, WSSs having a smaller scale than the conventional technique are used and the WSSs are internally-connected from a viewpoint different from that of the conventional technique, thus providing the device having a significantly-reduced cost.

Abstract: In a network protection method, a network node, and a communications system provided in embodiments of the present disclosure, when signal degrade or signal fail occurs in a service transmission path, a communication status of a source node of a current protection segment is obtained, and whether to perform protection switching is determined according to the communication status of the source node and a communication status of a local communication path. This can avoid erroneous switching to some extent, thereby improving protection switching accuracy of a communications network.

Abstract: A virtual local area network configuration system, a method and a computer program product thereof are provided. The virtual local area network configuration system includes physical machines running virtual machines, Ethernet switches and a network controller. The network controller deploys VLAN groups according to the physical machines and the virtual machines, creates virtual topologies corresponding to the VLAN groups and assigns VLAN IDs to the VLAN groups, wherein at least two VLAN groups among the VLAN groups have the same VLAN ID.

Abstract: Embodiments relate to providing simultaneous digital and analog services in optical fiber-based distributed radio frequency (RF) antenna systems (DASs), and related components and methods. A multiplex switch unit associated with a head-end unit of a DAS can be configured to receive a plurality of analog and digital downlink signals from one or more sources, such as a service matrix unit, and to assign each downlink signal to be transmitted to one or more remote units of the DAS. In one example, when two or more downlink signals are assigned to be transmitted to the same remote unit, a wave division multiplexer/demultiplexer associated with the multiplex switch unit can be configured to wave division multiplex the component downlink signals into a combined downlink signal for remote side transmission and to demultiplex received combined uplink signals into their component uplink signals for head-end side transmission.

Abstract: An illustrate method (and device) includes etching a cavity in a first substrate (e.g., a semiconductor wafer), forming a first metal layer on a first surface of the first substrate and in the cavity, and forming a second metal layer on a non-conductive structure (e.g., glass). The method also may include removing a portion of the second metal layer to form an iris to expose a portion of the non-conductive structure, forming a bond between the first metal layer and the second metal layer to thereby attach the non-conductive structure to the first substrate, sealing an interface between the non-conductive structure and the first substrate, and patterning an antenna on a surface of the non-conductive structure.

Abstract: Systems and methods for applying a pilot tone to multiple spectral bands are provided. An initial signal is divided into multiple spectral bands. A pilot tone is applied to each of the spectral bands, and then the signals are again combined for transmission. The pilot tones differ in some way, for example in phase or frequency.

Abstract: A buffer scheduling method is provided for use in an Internet data center in which flows are transmitted in a “Hybrid Switching Mode” using both an optical circuit switch and an electrical circuit switch or in an “All-optical Switching Mode” using only the optical circuit switch, to improve the overall switch throughput. In the “Hybrid Switching Mode,” an offloading scheme can be used; in the “All-optical Switching Mode,” a discard scheme, a padding scheme, a free-riding scheme, an aggregate scheme or a smart scheme can be used. During the transitioning stage of the technology, the offloading scheme can be used in the “Hybrid Switching Mode” to achieve significant improvement in the overall switching efficiency, whereas in the all-optical switching field, the free-riding scheme, the aggregate scheme and the smart scheme can be used to achieve good switching efficiency in the “All-optical Switching Mode.

Abstract: Systems and methods of coordinating Layer 1 and Layer 2 protection switching include, at a node having a plurality of ports including a first port that is an endpoint of a Layer 1 network and a second port that connects to a Layer 2 network, communicating defects in the Layer 1 network to a local Maintenance End Point (MEP) on the second port and any recovery actions being performed in the Layer 1 network; informing other nodes on the Layer 2 network via the second port of the defects and the recovery actions; and coordinating Layer 2 protection switching in the Layer 2 network based on the defects and based on the recovery actions in the Layer 1 network.

Abstract: A method is performed at a source node in a network of nodes configured with a link state protocol, and in which at least some of the nodes are enabled for multiprotocol label switching (MPLS). The node discovers and stores a link state topology representing the nodes of the network, links between the nodes, path-costs for the links, and whether each link is enabled or not enabled for MPLS. The node determines one or more shortest paths from the source node to a destination node among the nodes based on traversing the link state topology and, while the node traverses the link state topology, detects whether each shortest path supports or does not support MPLS end-to-end dataplane continuity. The node programs an IP dataplane with each shortest path, and programs an MPLS dataplane with ones of the one or more shortest paths that support the end-to-end MPLS continuity.

Abstract: A digital signal receiver comprises an iterative decoder configured to decode its input signal using an iterative decoding algorithm, a signal quality detector, configured to detect signal quality of the input signal of the iterative decoder; a power consumption monitor, configured to detect a parameter indicating power consumption of the iterative decoder; a voltage regulator, configured to adjust a supply voltage of the iterative decoder to maintain it within a preset supply voltage range, based on the detected parameter indicating the power consumption of the iterative decoder; and an iteration controller, configured to adjust a maximum iteration number of decoding based on the signal quality of the input signal of the iterative decoder.

Abstract: Systems, methods, and processor readable media for distributing digital data and electrical power to a plurality of devices over high-impedance cables are disclosed. Certain embodiments include a gateway device connected to a power source, a first device connected to the gateway device by a cable, the cable being a high-impedance cable having at least two conductive paths, and wherein the first device receives electrical power and digital data from the gateway device via the cable over the same conductive path of the cable, a second device connected to the gateway device by the cable wherein the second device receives power and digital data from the gateway device via the cable over the same conductive path, and wherein the power source provides power to the first and second devices via the cable, and wherein the second device is connected to the gateway device through the first device via a daisy-chain topology.

Abstract: Aspects of the subject disclosure may include, for example, a network device that accesses internet protocol addresses associated with a group of end point devices where the network device is a closest network device to the group of end point devices, and transmitting data to another network device responsive to a determination that an internet protocol address associated with the data from an end point device is one of the internet protocol addresses associated with the group of end point devices. Other embodiments are disclosed.

Abstract: A transceiver can include a transmitter and a receiver. The transmitter can include: a primary laser emitter; a primary monitor photodiode optically coupled with the laser emitter; a spare laser emitter; and a transmitter integrated circuit having a primary channel operably coupled with the primary laser emitter; a spare channel operably coupled with the spare laser emitter; a switch on the primary channel; and a secondary channel operably coupled with the switch and the spare channel. The receiver can include: a primary detector photodiode; a spare detector photodiode; and a receiver integrated circuit a primary receiver channel operably coupled with the at least one primary detector photodiode; a spare receiver channel operably coupled with the spare detector photodiode; a receiver switch on the spare receiver channel; and a secondary receiver channel operably coupled with the receiver switch and the primary receiver channel.

Abstract: A method for transmitting and receiving a radio frequency (RF) signal over an optical channel is described, where a nonlinear optical harmonic generation device is used to increase the system performance. The RF signal is phase modulated onto an optical carrier. The received optical carrier propagates through a nonlinear optical harmonic generation device, which increases a phase modulation depth at the harmonic wavelength. This larger modulation depth can be used to achieve larger gain. By photo-detecting both the fundamental and the harmonic optical wavelengths, then properly scaling and subtracting the two photo-detected signals, the enhanced modulation depth at the harmonic optical wavelength can be used to cancel out unwanted nonlinear distortions thereby linearizing the measured RF signal.

Abstract: Verifying a configuration of reconfigurable internal optical paths (970) in a wavelength selective optical switching WSS node (62) involves identifying which of several WSS subsystems (920, 950, 960) is coupled upstream of a first internal optical path based on detecting optical power distinctive of the upstream subsystem and carried to the downstream WSS subsystem. The detecting can be of a power of wavelengths used for traffic (110), or a power of optical noise when there is no traffic (120). A record is made of the identified configuration. The automated verification can be carried out without the conventional dedicated optical wavelengths or dedicated optical hardware for inserting such additional wavelengths dedicated to discovery, and without disrupting the traffic if upgrading a node. It can be controlled locally or by an NMS such as an SDN controller.

Abstract: A monitoring and troubleshooting system to determine whether or not an antenna that is used for receiving wireless weak signals, like base station for cellular wireless communication, is operational. The antenna status condition is signaled over the Fiber Optic (FO) link without interfering the signal during normal operation. When a fault is detected the status at the FO receiver is determined. Then, an indication using special signaling allows a service technician to distinguish if the status fault is antenna failure or antenna disconnect. The present invention will also allow a service technician to determine if there is a FO link failure by use of light intensity monitoring. The present invention also includes a method of monitoring the status of a radio frequency antenna with the apparatus as discussed above.