2029results about "Electromagnetic network arrangements" patented technology

The communication system includes a hybride fiber / coax distribution network. A head end provides for downstream transmission of telephony and control data in a first frequency bandwidth over the hybrid fiber / coax distribution network and reception of upstream telephony and control data in a second frequency bandwidth over the hybrid fiber / coax distribution network. The head end includes head end multicarrier modem for modulating at least downstream telephony information on a plurality of orthogonal carriers in the first frequency bandwidth and demodulating at least upstream telephony information modulated on a plurality of orthogonal carriers in the second frequency bandwidth. The head end further includes a controller operatively connected to the head end multicarrier modem for controlling transmission of the downstream telephony information and downstream control data and for controlling receipt of the upstream control data and upstream telephony information. The system further includes service units, each service unit operatively connected to the hybrid fiber / coax distribution network for upstream transmission of telephony and control data in the second frequency bandwidth and for receipt of the downstream control data and telephony in the first frequency bandwidth. Each service unit includes a service unit multicarrier modem for modulating at least the upstream telephony information on at least one carrier orthogonal at the head end terminal to another carrier in the second frequency bandwidth and for demodulating at least downstream telephony information modulated on at least a band of a plurality of orthogonal carriers in the first frequency bandwidth. Each service unit also includes a controller operatively connected to the service unit multicarrier modem for controlling the modulation of and demodulation performed by the service unit multicarrier modem. A method of monitoring communication channels, a distributed loop method for adjusting transmission characteristics to allow for transmission of data in a multi-point to point communication system, a polyphase filter technique for providing ingress protection and a scanning method for identifying frequency bands to be used for transmission by service units are also included. Also provided is a method and apparatus for performing a Fast Fourier Transform (FFT). In one embodiment, a scalable FFT system is built using a novel dual-radix butterfly core.

A method for testing a fiber drop terminal from a single geographic location may include placing a signal onto a first optical fiber at the single geographic location. The first optical fiber is communicatively coupled to a first output receptacle on the fiber drop terminal. The method may also include detecting the signal via a second optical fiber at the single geographic location. The second optical fiber is communicatively coupled to a second output receptacle on the fiber drop terminal, and the second output receptacle is communicatively coupled to the first output receptacle via a loop-back assembly.

An optical signaling header technique applicable to optical networks wherein packet routing information is embedded in the same channel or wavelength as the data payload so that both the header and data payload propagate through network elements with the same path and the associated delays. The header routing information has sufficiently different characteristics from the data payload so that the signaling header can be detected without being affected by the data payload, and that the signaling header can also be removed without affecting the data payload. The signal routing technique can be overlaid onto the conventional network elements in a modular manner using two types of applique modules. The first type effects header encoding and decoding at the entry and exit points of the data payload into and out of the network; the second type effects header detection at each of the network elements.

A system for data transport in a Distributed Antenna System (DAS) includes a plurality of remote Digital Access Units (DAUs) located at a Remote location. The plurality of remote DAUs are coupled to each other and operable to transport digital signals between the plurality of remote DAUs. The system also includes a plurality of central hubs. Each of the plurality of central hubs is in communication with one of the remote DAUs using an electrical communications path. The system further includes a plurality of transmit / receive cells. Each of the plurality of transmit / receive cells includes a plurality of remote hubs. Each of the remote hubs in one of the plurality of transmit / receive cells is in communication with one of the plurality of central hubs using an optical communications path.

One embodiment provides a system for power saving in an Ethernet Passive Optic Network (EPON). The system includes an optical line terminal (OLT), an optical network unit (ONU), a traffic-detection module configured to detect status of traffic to and from the ONU, and a power-management module configured to place the ONU in sleep mode based on the detected traffic status. The ONU includes an optical transceiver that includes an optical transmitter configured to transmit optical signals to the OLT and an optical receiver configured to receive optical signals from the OLT.

A system for powering a network element of a fiber optic wide area network is disclosed. When communication data is transferred between a central office (CO) and a subscriber terminal using a network element to convert optical to electrical (O-E) and electrical to optical (E-O) signals between a fiber from the central office and twisted wire pair, coaxial cable or Ethernet cable transmission lines from the subscriber terminal, techniques related to local powering of a network element or drop site by the subscriber terminal or subscriber premise remote powering device are provided. Certain advantages and / or benefits are achieved using the present invention, such as freedom from any requirement for additional meter installations or meter connection charges and does not require a separate power network.

An optical-fiber-network (OFN) radio-frequency identification (RFID) system for deploying and / or maintaining and / or provisioning service and / or locating faults in an OFN. The system includes a plurality of OFN components, and at least one RFID tag that includes RFID tag data that has at least one property of the OFN component associated with the RFID tag. The RFID tag data is written to and read from the RFID tags using one or more mobile RFID readers either prior to, during or after deploying the OFN components. An OFN-component-data database unit is used to store and process the RFID tag data and is automatically updated by the one or more mobile RFID readers. This allows for different maps of the OFN to be made, such as an inventory map and a maintenance map, and for the maps to be automatically updated. The OFN-RFID system allows for mobile automated operations and management of OFN components by service personnel, and provides for faster and more accurate OFN system deployment and maintenance.

One embodiment of the present invention provides a system that facilitates forwarding of packets in an Ethernet passive optical network (EPON), which includes a central node and at least one remote node. During operation, the system assigns a logical link identifier (LLID) to a remote node, wherein an LLID corresponds to a logical link between the central node and a remote node. The system also associates an LLID with a port of a switch within the central node, wherein the switch has a number of ports; wherein a port may be a physical port or a virtual port; and wherein the number of ports on the switch are divided into network-side ports and user-side ports. Upon receiving a downstream packet from a network-side port, the system searches a mapping table to determine whether one or more field values of the downstream packet correspond to any LLIDs or ports. If the one or more field values correspond to an LLID, the system assigns the LLID to the downstream packet and transmits the downstream packet to a remote node.

A SW (70) receives an Ethernet® signal from an outside of areas E and F. The SW (70) selects and outputs the obtained Ethernet® signal to any one of APs (91a to 91e) in accordance with a network structure managed by the SW (70). The AP (91a to 91e) converts the Ethernet® signal to an electrical signal type wireless LAN signal, which is in turn output to a main station (10). The main station (10) frequency-multiplexes the signal output from each of the APs (91a to 91e), and converts the signal to an optical signal, which is in turn output to sub-stations (20a and 20b) The sub-station (20a and 20b) transmits the signal transmitted from the main station (10) to a terminal in the form of a wireless radio wave. Thereby, when a plurality of communication areas are present, the accommodation capacity of an AP can be effectively utilized in each communication area.

Disclosed by the present invention is a system and method for optical fiber transmission. The switching portion of the present invention adopts the single-layered integrated switching technology so as to ensure a relatively simple and easy maintenance compared with the switching in a traditional communication network where said switching is made in the service network layer and the bearer network layer, respectively. Moreover, the present invention implements data transmission via optical fiber throughout the entire telecommunication system such that demands for bandwidth resources are satisfied during the whole data transmission process and the QoS (Quality of Service) of different services as well as rapid and un-blocking switching of the services are ensured in the telecommunication system. Therefore, the present invention can implement on-demand allocation of bandwidth resources, enhancing the flexibility in network resource management while a subscriber can apply for bandwidth resources based on its demand, which satisfies the individual needs of the user.

A system and method for managing the optical layer network data communications of an optical fiber data network by an optical transceiver module is disclosed. The management of the optical layer network data communications comprising data link layer functions or layer 2 functions in an OSI model. Benefits include reduction in reduced cost of network deployments from consolidation of network equipment, such as switches, and reduction in power consumed as well as enabling point-to-multipoint network connections from previously only point-to-point network connection.

A method for testing a fiber drop terminal from a single geographic location may include placing a signal onto a first optical fiber at the single geographic location. The first optical fiber is communicatively coupled to a first output receptacle on the fiber drop terminal. The method may also include detecting the signal via a second optical fiber at the single geographic location. The second optical fiber is communicatively coupled to a second output receptacle on the fiber drop terminal, and the second output receptacle is communicatively coupled to the first output receptacle via a loop-back assembly.

Provided are an apparatus and method for monitoring optical fibers of a passive optical network system including an optical line termination located in a central office, a remote node that is a local office, and optical network units on the subscriber side. The apparatus respectively allocates monitoring light wavelengths to optical network units such that optical fibers of the respective optical network units can be identified and monitored using the monitoring light wavelengths, combines a monitoring light having various wavelengths and a downward optical signal using the WDM coupler, and analyzes signal waveforms of the monitoring light having various wavelengths reflected from the optical network units, to detect the position of a defect generated on an optical line. Accordingly, it is possible to transmit optical signals and monitor the physical states of the optical fibers of the optical network units.

A data centre network, comprises a first group of optical ports for connection to respective servers of a first group of servers; a second group of optical ports for connection to respective servers of a second group of servers; a first lower passive optical routing element arranged to route optical communication signals between the first group of optical ports and a first lower optical communication path; a second lower passive optical routing element arranged to route optical communication signals between the second group of optical ports and a second lower optical communication path; an upper passive optical routing element arranged to: (i) route optical communication signals between the first lower optical communication path and an upper optical communication path, and (ii) route optical communication signals between the second lower optical communication path and the upper optical communication path.

A packet is routed by "dead reckoning" on a network having a generally regular topology. The packet is received at a node where a local routing decision is made. The packet is output in a direction selected according to the routing decision. The packet carries in addition to a destination address a directional flag indicating explicitly the preferred direction of onward travel and the routing decision is made using this flag. Several flags may be used, corresponding to different dimensions of the network.

The present disclosure provides hybrid packet-optical private network systems and methods for a private and dedicated multi-point Ethernet Private Local Area Network (EPLAN). The network systems and methods include a Layer 1 infrastructure service with the inclusion of reserved, dedicated packet switch capacity upon which clients can build their personal, private packet networks. In the systems and methods described herein, packet networking methods are not used to partition the isolated LAN connectivity. Instead, dedicated Ethernet Private LANs (EPLs) are defined between dedicated virtual switching instances (VSIs) that are defined, as necessary, within larger packet-optical switches. Each VSI is partitioned from the remainder of its packet switch fabric as a dedicated, private resource for a specific EPLAN. A packet network is then built by the customer on top of the private EPLAN bandwidth and operated as an isolated, private network with no influence by other carrier's network resources.

An optical transmitting apparatus is configured such that K pieces of output ports of optical path switching units whose input port is connected to k-th input transmission path are connected to first to K-th output transmission paths except for the k-th output transmission path and to the k-th input port of a dropping unit, and the optical path switching units and the dropping unit outputs light of wavelength which is part or all of WDM light received from said input port from a specific output port, and can output light having a wavelength different from that of the light output from said specific output port from an output port different from said specific output port. Accordingly, while largely reducing the number of optical fiber patch cords necessary in an optical transmitting apparatus and largely reducing the number of spare ports, the flexible expansion of apparatus function can be realized.

The present invention relates to a technology of an IP node for transferring IP packets accommodated in a wavelength division multiplexing optical signal. The optical IP node of the present invention includes a space switch unit supplied with a wavelength division multiplexing optical signal and a packet with another node destination and generating an optical signal with the self node destination and multiplexing the optical signal with another node destination and an optical signal caused by the packet together and generating the multiplexed signal, link failure detecting unit connected to an input side and an output side of the space switch unit, detecting link failure and generating a detection signal, an OAM packet transmitting unit for generating a monitoring packet at a predetermined time interval, and a traffic restoration control unit connected to the link failure detecting unit, selecting each optical signal depending on the wavelength in response to reception of the detection signal, switching the optical path and generating the optical signal. Each of the optical IP nodes carries out optical path switching on the wavelength division multiplexing optical signal and assignment of an IP packet to be transmitted to an optical signal and switching of the assignment. Thus, the number of optical wavelengths utilized for transmission can be reduced and the size of the optical IP node can be made small.

An architecture and method for performing coarse-grain reservation of lightpaths within wavelength-division-multiplexed (WDM) based photonic burst-switched (PBS) networks with variable time slot provisioning. The method employs extensions to the RSVP-TE signaling protocol, which uses various messages to reserve resources. A resource reservation request is passed between nodes during a downstream traversal of the lightpath route connecting a source node to a destination node via one or more switching nodes, wherein each node is queried to determine whether it has transmission resources (i.e., a lightpath segment) available during a future scheduled time period. Soft reservations are made for each lightpath segment that is available using information contained in a corresponding label. If all lightpath segments for a selected route are available, a reservation response message is sent back upstream along the route from the destination node to the source node. In response to receiving the response, the soft reservations are turned into hard reservations at each node.

An all optical network for optical signal traffic has at least a first ring with at least one transmitter and one receiver. The first ring includes a plurality of network nodes. At least a first add / drop broadband coupler is coupled to the first ring. The broadband coupler includes an add port and a drop port to add and drop wavelengths to and or from the first ring, a pass-through direction and an add / drop direction. The first add / drop broadband coupler is configured to minimize a pass-through loss in the first ring and is positioned on the first ring.

Systems and methods for data transport, including receiving one or more signals into a reconfigurable and flexible rate shared rate multi-transponder network architecture, wherein the network architecture includes one or more transponders with multiple line side interfaces and one or more client side interfaces. The transponders are configured to map one or more signals to multiple parallel Virtual Ethernet Links, remove idle characters from the one or more signals, buffer one or more blocks of characters using an intermediate block buffer, activate and deactivate one or more portions of input / output electrical lanes of an Ethernet module, multiplex and demultiplex the one or more signals to and from the input / output electrical lanes to enable sharing of a single optical transceiver by multiple independent signals, and insert blocks of idle characters to enable transmission over a lower rate transmission pipe.

The present invention relates to an optical cross connect unit comprising M wavelength separating sections for receiving multiplexed optical signals each having N kinds of wavelengths different from each other through M optical fibers, respectively, and for wavelength-separating each of the multiplexed optical signals into N optical signals, M optical reproduction relay sections each for conducting an optical reproduction and relay in a manner of making a conversion of each of the N optical signals, wavelength-separated in each of the wavelength separating sections, into an electric signal and then modulating it with a desired optical wavelength, a refill section for mutually refilling M sets of optical signals optically reproduced and relayed in the optical reproduction relay sections, a focusing section for focusing the M sets of optical signals refilled in the refill section, and a light source unit for supplying input lights having desired wavelengths to be modulated in the M optical reproduction relay sections. The light source unit includes N light sources for outputting lights having the N kinds of optical wavelengths, a multiplexing and branching section for multiplexing the lights from the N light sources to produce a multiplexed light having N kinds of optical wavelength components and further for branching the multiplexed light into MxN lights to output them as multiplexed and distributed lights, M wavelength filter sections for distributively receiving N multiplexed and distributed lights of the MxN multiplexed and distributed lights branched in the multiplexing and branching section to output N lights due to the passage of only arbitrary wavelengths of the N kinds of optical wavelengths, and a wavelength setting control section for setting optical wavelengths, which pass through the wavelength filter sections, so that they differ from each other. The N lights from each of the M wavelength filter sections are supplied as the input lights. In the case that many light sources are necessary for the modulation processing by modulators or the like, this optical cross connect unit is also suitable because of using given wavelengths from a small number of light sources for a lot of modulation processing.

A WDM optical transmission system of the invention has a configuration where WDM light generated at a wavelength multiplexing station is transmitted via a plurality of stations such as optical add-drop stations, arranged on an optical transmission line, and control of the power of the optical signals of respective wavelengths included in the WDM light is performed in the wavelength multiplexing station and the optical add-drop stations. A device is provided which communicates between stations, optical signals including information related to the control state of the optical signal power in each station, so that after control of the optical signal power at an upstream station is complete, control of the optical signal power at the downstream station is executed. As a result, stable control in respective stations can be performed even at the time of increasing or decreasing the number of wavelengths.

In an optical network some optical nodes are fitted with optical switches. The optical switches support the optical coupling and decoupling of the optical nodes and the remainder of the optical network. Electrical power supply failures to a node result in the node being optically decoupled from the remainder of the optical network thereby allowing the remaining nodes to continue normal operation.

An optical packet switch uses electric circuits to implement input and output sections of an optical switch that performs packet switching. Retiming of packet data in the output section is facilitated to reduce the scale of the circuitry. In the input section a packet-data signal and a clock signal for retiming the packet data are wavelength multiplexed by a wavelength multiplexer and transferred over the same optical waveguide of the optical switch. In the output section the packet-data signal and the clock signal, which have been transferred from the same optical waveguide in the packet switch, are demultiplexed by a wavelength demultiplexer, and retiming of the packet-data signal is performed by an intra-device frame terminating unit. A frame format comprises, in addition to a flag pattern and a data field, a preamble and dummy data at the beginning and end thereof, respectively, for accommodating skew caused by transfer through the optical switch as well as a period of signal instability produced by switching of the optical switch. The packet data is transferred upon being placed in the data field of the frame format.

One embodiment of the present invention provides a method for facilitating asymmetric line rates in an Ethernet passive optical network (EPON) which includes a central node and at least one remote node. During operation, the system provides a downstream code-group clock, wherein each cycle thereof corresponds to a code group transmitted from the central node to a remote node. The system also provides an upstream code-group clock, wherein each cycle thereof corresponds to a code group received at the central node from a remote node. In addition, the system provides a multi-point control protocol (MPCP) clock, wherein the frequency ratio of the MPCP clock to the downstream code-group clock is different from the frequency ratio of the MPCP clock to the upstream code-group clock, thereby allowing the downstream transmission to be performed at a faster line rate than the upstream transmission line rate.

A network includes a plurality of interconnected nodes utilizing an all-broadcast architecture for a plurality of wavelengths therebetween; a routing protocol configured to compute a loop-free path through the plurality of interconnected nodes, wherein the loop-free path is computed for at least one wavelength of the plurality of wavelengths using routing constructs adapted to a photonic domain; and at least one blocking element configured to selectively block the at least one wavelength based on the computed loop-free path. A routing method photonic node are also disclosed.

A bidirectional optical triplexer is disclosed, which may be connected to an external optical waveguide and receives first and second optical signals having first and second wavelengths through the external optical waveguide, and transmits a third optical signal having a third wavelength. The triplexer includes a platform having first and second trenches spaced from each other on a first optical path optically connected with the external optical waveguide, a first filter positioned in the first trench for reflecting the first optical signal proceeding through the first optical path to a second optical path, and a second filter positioned in the second trench for reflecting the second optical signal proceeding through the first optical path to a third optical path. The triplexer also includes a first optical receiver for detecting the first optical signal proceeding through the second optical path, a second optical receiver for detecting the second optical signal proceeding through the third optical path, and an optical transmitter for outputting the third optical signal to the first optical path. The first and the second optical receiver may be aligned at a first side of the first and the second trenches and the optical transmitter may be aligned at a second side of the first and the second trenches. The first side is opposite to the second side about the first and second trenches.

A network comprising a large number of electronic edge nodes interconnected through bufferless optical switch planes so that a signal from any edge node to any other edge node traverses only one switch plane scales to a capacity of hundreds of petabits per second while providing global geographic coverage. Each edge node is time-locked to each optical switch plane to which it connects to enable loss-free time-sharing of the network core despite the absence of buffers in the core. In an alternate implementation, a relatively small number of electronic switch units may be employed in a predominantly-optical core. In addition to scalability and high performance, the simple structure of the network significantly simplifies addressing and routing.