Abstract: An optical line terminal (OLT) performs power management control in a passive optical network (PON) by acquiring a respective reception level for each optical network unit (ONU) in the PON and maintaining a reception table that stores the respective reception level for each ONU. Prior to receiving a burst signal from an ONU, it sets a reception threshold of an optical receiver at the OLT with the reception level of the ONU.

Abstract: Embodiments of the present invention exploit the existing capabilities of the Ethernet Passive Optical Network (EPON) MAC layer, designed for fiber optics communications, to provide a low cost MAC layer with upper layer connectivity over a hybrid fiber coaxial (HFC) network. In particular, embodiments allow for the EPON MAC to be used end-to-end (i.e., from an optical line terminal (OLT) to a coaxial network unit (CNU)) in a HFC network, thereby fully leveraging the packet processing capabilities, QoS functions, and management features of the EPON MAC. Furthermore, embodiments enable unified provisioning and management for both fiber and coaxial network units in a HFC network.

Abstract: An apparatus including a section acquiring the information as to the information processor of the delivery destination in the second network, a section alternatively providing service to an access from the first network by using the acquired information, a section receiving and delivering the information from the first network by using the alternatively supplied service, a section changing the information processor of the delivery destination in the second network to the service providing state, when the apparatus receives the information including the contents from the first network and the information processor of the delivery destination in the second network is not in the service providing state, it is possible to change the information processor of the delivery destination to the service providing state and deliver information including the contents to the information processor of the delivery destination.

Abstract: In an optical element integrated module, first through n-th optical data signals are externally input to first ports of first through n-th optical circulators and are input to first through n-th optical/optical converters via second ports. The first through n-th optical/optical converters modulate first through n-th optical short pulse trains in accordance with the first through n-th optical data signals. First through n-th modulated optical data signals are input to the second ports of the first through n-th optical circulators and are input to an optical time division multiplexing section. The optical time division multiplexing section generates optical time division multiplexed signals by time division multiplexing the first through n-th modulated optical data signals.

Abstract: Systems and methods for signal conversion with smart multitap are disclosed. Embodiments of the systems can be scalable to model different signal topologies, transmission frequencies, bandwidths, and distances. An exemplary embodiment of the systems and methods includes a fiber optic to RF converter and a smart multitap. Although a fiber optic to RF converter is used in exemplary embodiments throughout the disclosure, conversion between other signal topologies is within the scope of the disclosure. The smart multitap includes a multiple tap for distributing a signal to multiple terminals and a microprocessor to select a particular terminal for a signal. Exemplary embodiments include downstream implementations in which a stream is typically sent from a service provider server to a user. Alternative embodiments include downstream implementations as well as upstream implementations in which a user typically sends a stream to a service provider server.

Abstract: A method and system for averaging the effects of polarization distortions across a multitude of transmitted data streams in a dual polarization multiplexed optical communications system. Data streams are interleaved amongst each other in accordance with a predetermined pattern. The interleaved data streams are symbol mapped and modulated to provide a pair of optical signals. The pair of optical signals are orthogonally polarized, and multiplexed for transmission across an optical fiber. A receiver circuit receives the transmitted signal and extracts the interleaved data streams. The interleaved data streams are de-interleaved to generate the original data streams. While the data streams can be interleaved and transmitted via a single wavelength optical signal, the data streams can be interleaved and transmitted over two or more different wavelength optical signals to further mitigate the effects of polarization distortions.

Abstract: Various embodiments of the present invention are directed to photonic-based interconnects for transmitting data encoded in electromagnetic signals between electronic mosaics. In one embodiment of the present invention, a photonic-based interconnect comprises a first photonic node coupled to a second photonic node via a waveguide. The first photonic node is coupled to a first electronic mosaic and is configured to transmit electromagnetic signals encoding data generated by the first electronic mosaic to a second electronic mosaic and receive electromagnetic signals encoding data generated by the second electronic mosaic. The second photonic node is coupled to the second electronic mosaic and is configured to transmit electromagnetic signals encoding data generated by the second electronic mosaic to the first electronic mosaic and receive electromagnetic signals encoding data generated by the first electronic mosaic.

Abstract: A device determines a bandwidth demand for traffic provided between a line terminal (LT) and multiple optical network terminals (ONTs), and dynamically tunes, based on the determined bandwidth demand, one or more tunable filters provided in the LT and the multiple ONTs to one of balance the traffic, protect the traffic, or increase available bandwidth for the traffic.

Abstract: Systems and methods for signal conversion with smart multitap are disclosed. Embodiments of the systems can be scalable to model different signal topologies, transmission frequencies, bandwidths, and distances. An exemplary embodiment of the systems and methods includes a fiber optic to RF converter and a smart multitap. Although a fiber optic to RF converter is used in exemplary embodiments throughout the disclosure, conversion between other signal topologies is within the scope of the disclosure. The smart multitap includes a multiple tap for distributing a signal to multiple terminals and a microprocessor to select a particular terminal for a signal. Exemplary embodiments include downstream implementations in which a stream is typically sent from a service provider server to a user. Alternative embodiments include downstream implementations as well as upstream implementations in which a user typically sends a stream to a service provider server.

Abstract: A wavelength division multiplexing based passive optical network is disclosed. The network includes an optical line terminal; a power optical splitter connecting to the optical line terminal by an optical fiber; and several optical network units. Each of the optical network units connects to the power optical splitter by each of other optical fibers by a random process.

Abstract: In a PON system with WDM, at the time of initial setting, each ONU negotiates with an OLT, and automatically acquires a wavelength which can be used by the ONU. One wavelength for negotiation of assigned wavelength is fixed as a default, and a newly connected ONU first uses the wavelength. The OLT 200 includes a plurality of light sources for downstream communication. The ONU 300 includes a wavelength variable filter selectively receiving one of wavelengths of downstream communication, and a wavelength variable light source selectively emitting light of one of plural wavelengths for upstream communication. The ONU 300 uses a transmission wavelength (for example, ?u32) for negotiation and transmits a wavelength assignment request 1000 to the OLT 200. The OLT 200 selects a wavelength ?u1 to be assigned from unused wavelengths, and transmits wavelength information to the ONU 300. The OLT 200 and the ONU 300 communicates using the notified wavelengths.

Abstract: A system and method for simultaneous delivery of a plurality of independent blocks of 500 MHz digital broadcast television services, stacking a plurality of RF blocks on a plurality of spectrally sliced WDM optical bands.

Abstract: A WDM communication system that includes links traversing substantially inaccessible regions may tolerate multiple failures. In one implementation, a primary link spanning such a region is protected by a backup link. To provide further fault tolerance diverse paths may be provided to and from this backup link. The region may be, for example, an ocean.

Abstract: The present invention provides TDM service, such as DS1, E1, or DS3, in a GPON system that is cost-effective, flexible, and that is easily configured and reconfigured. A system for telecommunications comprises circuitry operable to receive time division multiplexed data traffic, circuitry operable to form Virtual Tributary encapsulated data traffic including the time division multiplexed data traffic, circuitry operable to transmit the Virtual Tributary encapsulated data traffic, circuitry operable to receive the Virtual Tributary encapsulated data traffic, and circuitry operable to extract the time division multiplexed data traffic from the Virtual Tributary encapsulated data traffic.

Abstract: A radio-over-fiber (RoF) wireless picocellular system adapted to form an array of substantially non-overlapping individual picocells by operating adjacent picocells at different frequencies is operated to form one or more combined picocells. The combined picocells are formed from two or more neighboring picocells by the central head-end station operating neighboring picocells at a common frequency. Communication between the central head-end station and a client device residing within a combined picocell is enhanced by the availability of two or more transponder antenna systems. Thus, enhanced communication techniques such as antenna diversity, phased-array antenna networks and multiple-input/multiple-output (MIMO) methods can be implemented to provide the system with enhanced performance capability. These techniques are preferably implemented at the central head-end station to avoid having to make substantial changes to the wireless picocellular system infrastructure.

Abstract: A wavelength-division-multiplexed based photonic burst switched (PBS) network, which includes edge and switching nodes, optically communicate information formatted into PBS control and data burst frames. Each PBS data burst frame is associated with a PBS control burst frame. A PBS burst frame includes a PBS burst header and burst payload having fields to indicate whether: (a) the PBS burst frame is a PBS control burst; (b) the control burst is transmitted on a wavelength different from that of the associated PBS data burst; and (c) the PBS burst frame has a label for use in a generalized multi-protocol label swapping (GMPLS)-based control system. The PBS burst payload frame includes fields to indicate (a) specific PBS payload information; (b) PBS data payload; and (c) an optional PBS payload frame check sequence (FCS) for error detection.

Abstract: A system and method for a transparent WDM metro ring architecture in which optics enables simultaneous provisioning of dedicated wavelengths for high-end user terminals, while low-end user terminals share wavelengths on “virtual rings”. All wavelengths are sourced by the network and remotely modulated at customer “End Stations” by low cost semiconductor optical amplifiers, which also serve as transmission amplifiers. The transparent WDM metro ring architecture permits the communication of information and comprises a fiber optical feeder ring, at least one fiber optical distribution ring, a network node (NN), at least one access node (AN) said network node and said at least one access node connected via said fiber optical feeder ring and at least one end station (ES) connected via said fiber optical distribution ring to said at least one access node, wherein said user is attached to said at least one end station.

Abstract: Methods and apparatus are described for simultaneous transport of analog video signals and Ethernet data on an optical fiber. A method includes propagating a downstream signal on an optical signal conductor from an upstream combiner to a downstream combiner; and propagating an upstream signal on the optical signal conductor from the downstream combiner to the upstream combiner.

Abstract: A station-side apparatus adapted for use in a passive optical network (PON) system is disclosed, which remotely collects inside information of optical network terminals (ONTs) even before completion of start-up of an optical network unit (ONU), permits an obstruction-detected ONU to send out an emergency notification message to the station-side apparatus, e.g., optical line terminal (OLP), and permits the OLT that received this message to interrupt the transmission of an upload signal toward another ONU after the elapse of a fixed length of time while at the same time receiving information from the obstruction-suffering ONU to thereby facilitate cut-and-divide or “segmentation” of obstruction. A subscriber-side device for use in the PON system is also disclosed.

Abstract: This invention provides a new architecture for a communication system between head-ends and end-users which expands bandwidth and reliability of the communication system. A mux-node receives communication signals from a head-end and forwards the received communication signals to one or more mini-fiber nodes. The connection to the head-end is via a small number of optical fibers and the connections to each of the mini-fiber nodes may be via one or more optical fibers that may provide full duplex communication. The head-end may communicate with the mux-node using digital or digital and analog signals. The mini-fiber nodes may combine the signals received from the head-end with loop-back signals used for local media access control prior to forwarding the signals to the end-users. Upstream data are received by the mini-fiber nodes and transmitted to the mux-node.

Abstract: In a Wavelength Division Multiplexed Passive Optical Network (WDM-PON) including, a system for distributing uplink, downlink and RF/Video broadcast signalling. An Array Waveguide Grating (AWG) couples respective wavelength channels between a trunk fibre of the WDM-PON and a plurality of branch fibers of the WDM-PON. The AWG has a predetermined free spectral range and implements a channel plan comprising at least three spectral segments, each segment having a width equal to the free spectral range of the AWG. An Optical Line Terminal of the WDM-PON receives wavelength division multiplexed uplink signals within a first one of the spectral segments, and transmits wavelength division multiplexed downlink signals within a second one of the spectral segments. Respective channel plans within the first and second spectral segments are identical. An RF/Video broadcast transmitter generates an RF/Video broadcast signal within a third one of the spectral segments.

Abstract: A DWDM optical system in a first embodiment includes a plurality of scramblers on the transmit side and a plurality of corresponding de-scramblers on the receiver side of the DWDM system. Each scrambler includes an input for an encryption key with the corresponding de-scrambler including an input for the same encryption key. In accordance with the pseudorandom encryption key, input data channels are scrambled onto output optical channels to provide data security across the optical path. With a suitable algorithm, this technique can provide very strong data confidentiality. The strength of the technique of the embodiments of the invention resides in the scrambling algorithm that is used to scramble the data over the optical carriers. Preferably the scrambling algorithm is very unpredictable and does not repeat for a very long time.

Abstract: In order to increase the capacity of a deployed passive optical network (PON) without replacing optical network terminators (ONTs), a PON is provided that is partitioned into multiple channels. The upstream and downstream channels in the PON are partitioned into M channels, with the number of channels on the upstream preferably equaling the number of channels on the downstream. In the downstream, the partitioning is accomplished by use of wavelength division multiplexing filters arranged in a way as to place groups of ONTs on M different wavelength bands, where all of the wavelength bands are within the downstream wavelength range of the existing PON. On the upstream, partitioning is accomplished using “injection locking” to narrow the possible wavelength range of each ONT transmitter to a portion of that possible in the existing PON.

Abstract: An aggregation node device of a passive optical network (PON) is provided which includes an aggregation optical line terminal (OLT) and an aggregation optical network unit (ONU). The aggregation OLT is connected to a user-side ONU. The aggregation OLT aggregates service data transmitted by a user-side ONU and transmits the aggregated service data to the aggregation ONU. The aggregation ONU is adapted to transmit the received aggregated service data to a network-side OLT. A PON system is further provided. The device and system can not only support the conventional time division multiplexing (TDM) services but also support the services based on variable-length packets and the multicast service. Moreover, it is not necessary to build an equipment room and supply power for an intermediate optical distribution network (ODN) which greatly reduces the network construction and operation costs.

Abstract: A method and system for ensuring confidentiality of signal transmission in a point-to-multipoint data transmission network like Ethernet passive optical network, including at least one hub, at least one transmission medium and at least one station connected to the hub via the transmission medium. When an upstream signal is transmitted from a first station, the upstream signal is reflected by at least one disturbing reflector for producing a disturbing reflection. The disturbing reflection combines with a second reflection of the upstream signal and renders the second reflection undecodable by a second station.

Abstract: The invention aims to provide an optical transmission system that specifies such a transmission condition so as to obtain high spectrum efficiency and a large transmission distance-capacity product at the same time, and uses low cost and small sized optical senders and optical receivers, to realize a high density wavelength multiplexing optical transmission. For this purpose, a WDM optical transmission system of the invention has a system structure that specifies by calculation the spectrum efficiency at which transmission distance-capacity product becomes a maximum value based on the determination of the type of signal light modulation and the assumption of an equation model expressing transmission characteristics of an optical multiplexer and an optical demultiplexer, and optimizes a bit rate and frequency spacing of signal light output from each optical sender, and the transmission characteristics of the optical multiplexer and the optical demultiplexer, so as to approach the spectrum efficiency.

Abstract: By using wavelength division multiplexing technologies, redundant star topology network is constructed on a ring-shaped optical fiber network. Edge-switches 5a, 5b, 5c, and 5d are connected to client station groups 6a, 6b, 6c, and 6d are connected, respectively. The edge-switches 5a, 5b, 5c, and 5d are connected to edge optical transport device 2a, 2b, 2c, and 2d. Core-switches 4a and 4b are connected to a core optical transport device 1. The edge optical transport device 2a, 2b, 2c, 2d, and the core optical transport device 1 are connected to a ring-shaped single optical fiber 3. A communication circuit 7 is formed among core optical transport device 1, edge optical transport devices 2a, 2b, 2c, and 2d, by using wavelength division multiplexing technologies.

Abstract: The present invention discloses a method and a system for transparent transport of optical channel transmission unit (OTU) signals via an optical transport network (OTN), which includes a transmitting unit and a receiving unit at the OTN network boundary: the transmitting unit converts an OTUj signal mapping entering the OTN network into OTUk signals of the current OTN network for transmission. In the mean time, it reserves the OTUj control overhead, or extracts the OTUj control overhead and transfers it to the reserved overhead location; the receiving unit receives the OTUk signals arriving at the OTN network boundary, and performs demapping and converting them into OTUj signals.

Abstract: Provided are extendable loop-back passive optical network (PON) and scheduling method and apparatus for the same. The loop-back type PON includes an OLT (optical line terminal) including a wavelength-tunable optical transmitter and a wavelength-locked optical receiver, and an RN (remote node) including an optical coupler/splitter, the optical coupler/splitter receiving optical signals from the wavelength-tunable optical transmitter and splitting the optical signals by wavelength so as to transmit the optical signals to corresponding ONTs (optical network terminals). Each of the ONTs transmits upstream data to the OLT using the same wavelength as the wavelength of the optical signal received from the OLT through the RN. Since the optical network makes use of the TDM and WDM communication schemes, the optical network can be maintained and upgraded at lower cost.

Abstract: This invention provides a new architecture for a communication system between head-ends and end-users which expands bandwidth and reliability of the communication system. A mux-node receives communication signals from a head-end and forwards the received communication signals to one or more mini-fiber nodes. The connection to the head-end is via a small number of optical fibers and the connections to each of the mini-fiber nodes may be via one or more optical fibers that may provide full duplex communication. The head-end may communicate with the mux-node using digital or digital and analog signals. The mini-fiber nodes may combine the signals received from the head-end with loop-back signals used for local media access control prior to forwarding the signals to the end-users. Upstream data are received by the mini-fiber nodes and transmitted to the mux-node.

Abstract: An optical repeater device of the present invention comprises: a preamble compensating circuit 53, for taking out a normal data signal from burst signals propagating through a communication transmission path, and for adding a preamble signal before and/or after the data signal. Furthermore, the preamble compensating circuit 53 comprises: a detector circuit 53a, for inputting the burst signal, and for outputting only the normal data signal; a buffer circuit 53b, for storing the data signal output from the detector circuit 53a, and for outputting thereof; a preamble signal generation circuit 53d, for outputting at least one type of the preamble signal; and an data output select circuit 53e, for outputting the data signal at the time of the data signal input from the buffer circuit 53b, and for outputting the preamble signal from the preamble signal generation circuit 53d at any other time thereof.

Abstract: Systems and methods for signal conversion with smart multitap are disclosed. Embodiments of the systems can be scalable to model different signal topologies, transmission frequencies, bandwidths, and distances. An exemplary embodiment of the systems and methods includes a fiber optic to RF converter and a smart multitap. Although a fiber optic to RF converter is used in exemplary embodiments throughout the disclosure, conversion between other signal topologies is within the scope of the disclosure. The smart multitap includes a multiple tap for distributing a signal to multiple terminals and a microprocessor to select a particular terminal for a signal. Exemplary embodiments include downstream implementations in which a stream is typically sent from a service provider server to a user. Alternative embodiments include downstream implementations as well as upstream implementations in which a user typically sends a stream to a service provider server.

Abstract: Systems and methods for unidirectional communication in an optical network employing bidirectional transponders are provided. The modulation and amplification capabilities of the bidirectional transponder are used to forward information to the next node. In this way a highly cost-effective “drop and continue” architecture is provided. In one implementation, the client-side output of the bidirectional transponder is looped back to the client-side input using, e.g., a Y-cable fiber. In this way, a unidirectional signal present on a network-side input wavelength to the transponder is presented both on a network-side output wavelength of the transponder and at the same time to a client. The modulation and amplification capabilities of the bidirectional transponder are thus exploited in forwarding the unidirectional signal to the next node.

Abstract: A Passive Optical Network includes: an Optical Line Terminal, an Optical Distribution Network, and an Optical Network Unit or an Optical Network Terminal, wherein the Optical Line Terminal is adapted to exchange data with the Optical Network Unit or the Optical Network Terminal by using an optical module via the Optical Distribution Network, and the optical module is an optical module sending data in a continuous mode. Further, a method for data communication based on the Passive Optical Network includes: sending data by using an optical module sending data in a continuous mode; receiving the data by an optical module based on a set optical power threshold of data “0” and a set optical power threshold of data “1”.

Abstract: Provided are a photonic cross-connector system, a wavelength division multiplexing (WDM) system using the photonic cross-connector system, and an optical communication network based on the WDM system. The photonic cross-connector system includes: an optical coupler branching an input optical signal into a plurality of paths; a wavelength selective switch (WSS) extracting at least one wavelength signal from the input optical signal and outputting the extracted wavelength signal to at least one port; a WDM multi-casting apparatus simultaneously copying and reproducing the input optical signal into different wavelengths and changing modulation methods of the input optical signal into different types of modulation methods; an optical transmitter and/or receiver branching and coupling the input optical signal; and a control system controlling the optical coupler, the WSS, the WDM multicasting apparatus, and the optical transmitter and/or receiver.

Abstract: Multi-channel Fabry-Perot laser transmitters and methods of generating multiple modulated optical signals are described. In one aspect, an optical transmitter includes a Fabry-Perot (FP) laser, an optical isolator, an optical splitter, and multiple electroabsorption modulators (EAMs). The FP laser is operable to generate multimode laser light. The optical isolator is arranged to transmit the multimode laser light. The optical splitter has more than one optical output and an optical input that is arranged to receive the multimode laser light transmitted by the optical isolator. Each of the EAMs is operable to modulate a respective laser light output from a respective optical output of the optical splitter. In another aspect, multimode laser light is generated. The multimode laser light is directionally isolated. The directionally-isolated multimode laser light is divided into more than one divided laser light output.

Abstract: Provided are methods of transmitting and receiving a multicast or broadcast frame in an optical line terminal (OLT) and an optical network unit (ONU) for a wavelength division multiplexing (WDM)-passive optical network (PON), a WDM-PON system, and an OLT for a WDM-PON. The method of transmitting a multicast or broadcast frame in an OLT for a WDM-PON includes converting and splitting a multicast or broadcast frame input using a single wavelength into a plurality of wavelengths, combining the split wavelengths, and outputting the multicast or broadcast frame. In this way, a multicast or broadcast frame can be transmitted and received, thereby providing a single copy broadcast (SCB) function in a WDM-PON.

Abstract: Methods and apparatus are described for fiber-to-the-home (FTTH) RF over Glass (RFoG) Architecture and customer-premise-equipment (CPE). A method includes up-converting a baseband upstream data signal to a frequency band above a frequency band of a baseband downstream data signal; combining the up-converted upstream data signal with an upstream cable return; transmitting the up-converted upstream data signal and the upstream cable return using a single upstream laser; separating the frequency up-converted data signal from the upstream cable return using an RF diplexer; and down-converting the frequency up-converted upstream data signal back to baseband.

Abstract: There is provided a wavelength division multiplexing transmission system and apparatuses used therein, in which a remote apparatus to be newly added to a station apparatus autonomously sets a wavelength to be used in the remote apparatus, thereby avoiding the need for presetting a wavelength to be used in the remote apparatus. The remote apparatus includes wavelength determining means that determines an available wavelength on the basis of an optical signal received from the station apparatus. The wavelength determining means may determine the wavelength of an unreceived optical signal as the available wavelength or may determine the wavelength of a received optical signal as the available wavelength, and may set that wavelength as a transmission and reception wavelength to be used in the remote apparatus.

Abstract: A communication system between head-ends and end-users is provided which expands bandwidth and reliability. A concentrator receives communication signals from a head-end and forwards the received communication signals to one or more fiber nodes and/or one or more mini-fiber nodes. The concentrator demultiplexes/splits received signals for the mini-fiber nodes and the fiber nodes and forwards demultiplexed/split signals respectively. The mini-fiber nodes may combine signals received from the head-end with loop-back signals used for local medium access control prior to forwarding the signals to the end-users. Upstream data are received by the mini-fiber nodes and/or fiber node and transmitted to the concentrator. The concentrator multiplexes/couples the mini-fiber node and the fiber node upstream signals and forwards multiplexed/coupled signals to the head-end.

Abstract: An Ethernet-based next generation optical transport network apparatus and a traffic grooming method in the apparatus are disclosed to provide a traffic grooming function to simultaneously transmit Ethernet data and a TDM signal through the same wavelength and provide a differentiated protection switching function by the flows to effectively support an Ethernet service in an optical transport network.

Abstract: A technique for asymmetric transport is disclosed. In one particular exemplary embodiment, the technique may be realized by/as a method for asymmetric transport. The method may comprise transmitting, from a network element, at least one first signal through at least one first transport interface at a first rate, where the at least one first transport interface accommodates the transmission of the at least one first signal through an optical medium. The method may also comprise receiving, at the network element, at least one second signal through at least one second transport interface at a second rate different from the first rate, where the at least one second transport interface accommodates the reception of the at least one second signal through the optical medium. At least one of the at least one first transport interface and the at least one second transport interface may be integrated with the network element.

Abstract: In accordance with the teachings of the present invention, a system and method for transmitting traffic in a plurality of passive optical networks (PONs) is provided. In a particular embodiment, a method for transmitting traffic in a plurality of passive optical networks (PONs) includes transmitting traffic at a first wavelength and at a second wavelength from an optical line terminal (OLT). The method also includes combining the traffic in the first wavelength and the traffic in the second wavelength and splitting the combined traffic into a plurality of copies. The method further includes forwarding a first copy to a first wavelength router at a first distribution node and forwarding a second copy to a second wavelength router at a second distribution node, wherein the first wavelength router is coupled to a first set of optical network units (ONUs) and the second wavelength router is coupled to a second set of ONUs.

Abstract: A Wavelength Division Multiplexed Passive Optical Network (WDM-PON) includes: a respective Optical Network Terminal (ONT) at each one of a plurality of customer sites, each ONT comprising an ONT Fabry Perot (F-P) laser for generating a respective broadband multi-mode uplink optical signal; and an Array Waveguide Grating (AWG) for receiving each broadband multi-mode uplink optical signal through a respective branch port, and for multiplexing a portion of each received broadband multi-mode uplink optical signal into a Wavelength Division Multiplexed (WDM) signal. Each ONT F-P laser is non-injection locked. A gain of each ONT F-P laser is sufficiently inhomogeneous that the modes of the respective broadband multi-mode uplink optical signal are independent. A filter function of the AWG includes a pass band that encompasses at least one mode of a broadband multi-mode uplink optical signal.

Abstract: An optical communication system for transmitting telephone voice data to a subscriber terminal using an optical line is disclosed. The system includes an OLT (Optical Line Terminal) multiplexing the telephone voice data together with the broadcasting data and communication data, converting the optical signals transferred upward into electric signals, demultiplexing and converting the uplink telephone voice data into analog telephone voice signals to transfer the converted analog telephone voice signals to a PSTN; a plurality of ONTs (Optical Network Terminals) for converting the optical signals transferred from the OLT into electric signals, demultiplexing and converting the demultiplexed downlink telephone voice data into analog signals to transfer the converted analog signals to subscribers' telephones; and an optical branching filter for branching the signals from the OLT to the plurality of ONTs, combining, and transferring the signals from the plurality of ONTs to the OLT.

Abstract: The present disclosure provides a system and method for allocating bandwidth in remote equipment on a passive optical network (PON), wherein the system includes an optical line terminal (OLT), which monitors the acceptance of traffic requesting the PON remote equipment for service and configures through signaling control the parameters for the operation of classifying, shaping, and scheduling the traffic in the remote equipment, and a remote equipment which classifies, shapes, and schedules the accepted traffic based on the parameters configured by the OLT and allocates a proper bandwidth to the accepted traffic, and outputs the traffic in the scheduled order. The present disclosure helps ensure the bandwidth and delay requirements of individual traffic flows in the PON remote equipment are met and interaction between traffic of the same or different service class groups is eliminated.

Abstract: An optical wavelength division multiplexer/demultiplexer device is described that comprises a substrate having a plurality of wavelength selecting filters. The filters are arranged to provide conversion between a combined beam comprising a plurality of wavelength channels and a plurality of separate beams each comprising a subset of said plurality of wavelength channels. Hollow core waveguides are formed in said substrate to guide light between the wavelength selecting filters. An add/drop multiplexer is also described.

Abstract: The present invention provides an optical link monitoring system for the passive optical network. The system includes a master monitoring device connected to an optical line terminal and a plurality of response devices respectively connected to a plurality of optical network units. Through time division multiplexing technology, the master monitoring device broadcasts a predetermined instruction to the response devices to answer back predetermined optical signals in turn. The master monitoring device also measures the optical power of the returned predetermined optical signals and diagnoses the status of the optical links. The present invention also provides an optical link monitoring method.

Abstract: There is provided a wavelength division multiplexing transmission system and apparatuses used therein, in which a remote apparatus to be newly added to a station apparatus autonomously sets a wavelength to be used in the remote apparatus, thereby avoiding the need for presetting a wavelength to be used in the remote apparatus. The remote apparatus includes wavelength determining means that determines an available wavelength on the basis of an optical signal received from the station apparatus. The wavelength determining means may determine the wavelength of an unreceived optical signal as the available wavelength or may determine the wavelength of a received optical signal as the available wavelength, and may set that wavelength as a transmission and reception wavelength to be used in the remote apparatus.

Abstract: The invention is related to an injection light generator for use in a wavelength division multiplexed-passive optical network, which generates A-band injection light having a spectrum range separated into N wavelength ranges (N is a natural number equal to or greater than 2) to be used for a transmission of a downstream optical signal and B-band injection light having a spectrum range separated into N wavelength ranges to be used for a transmission of an upstream optical signal.