Abstract: A method for enabling alternating current (AC) coupling of high-speed burst data signals transmitted by an optical network unit (ONU). The method comprises generating a first data pattern to be sent to an optical transceiver through an AC coupling circuit, wherein the first data pattern is a direct current (DC) balanced pattern; generating a second data pattern to be sent to the optical transceiver through the AC coupling circuit, wherein the second data pattern is output prior to transmission of a high-speed burst data signal; and generating a third data pattern to be sent to the optical transceiver through the AC coupling circuit, wherein the third data pattern is output posterior to the transmission of the high-speed burst data signal.

Abstract: A passive optical network (PON) comprises an Optical Line Termination (OLT), an Optical Distribution Network (ODN), and a plurality of Optical Network Terminations (ONTs), wherein the OLT includes an OLT Dense Wavelength Division Multiplexing (DWDM) multiplexer, an OLT CWDM demultiplexer, and a Wavelength Division Multiplexing (WDM) filter, wherein the OLT DWDM multiplexer and the OLT CWDM demultiplexer are coupled to the WDM filter, wherein the ODN includes a WDM filter, a DWDM demultiplexer, and a plurality of fanout splitters, wherein the DWDM demultiplexer is coupled to the WDM filter, wherein the WDM filters are coupled to one another and wherein a portion of the plurality of ONTs that are associated with a wavelength are coupled to one of fanout splitters that is associated with the wavelength.

Abstract: An optical communications network that is composed of one station-side equipment being connected to plural subscriber-side equipments. The station-side equipment refers to downstream data signals and prepares transmission plans, and generates downstream control signals that include the transmission plans, and converts downstream signals, that include the downstream data signals and the downstream control signals to which identifiers indicating the subscriber-side equipments that are addressees are assigned, into downstream optical signals, and sends the downstream optical signals out toward the subscriber-side equipments.

Abstract: According to one general aspect, an interconnection node may be configured to dynamically provide interconnection access between a first optical network (e.g., a core optical network) and at least either a second optical network (e.g., an access optical network) or a third optical network (e.g., another access optical network) in a purely optical fashion. The interconnection node may include a first network portion and a second and third network portions. The first network portion may be coupled with the first network that includes a first pair of wavelength cross-connect (WXC) units coupled between a first transmission path of the first network, and providing a plurality of add and drop ports, and a second pair of wavelength cross-connect (WXC) units coupled between a second transmission path of the first network, and providing a plurality of add and drop ports.

Abstract: A method, equipment, and operation management system for detecting and authenticating a terminal in a passive optical network are provided. The method includes the following steps. The terminal has a logic registration code. A central office end receives the logic registration code sent by the terminal. The central office end judges whether the logic registration code of the terminal matches with the logic registration code stored at the central office end, and determines that the terminal is a valid terminal if the logic registration code sent by the terminal matches with the logic registration code stored at the central office end. The central office end records a terminal serial number from the valid terminal, and records a terminal identifier assigned to the valid terminal.

Abstract: A point-to-multipoint optical communication network includes a fiber optic cable, and a single photodiode for optical/electrical conversion at the upstream end of the cable. On the other hand, an “n” number of electrical/optical up-converters are connected between an “n” number of downstream points and the downstream end of the cable. Within this arrangement, radio frequency signals “fn” from respective “n” different downstream points are impressed onto respective wavelengths “?n”. The resultant optical signals “?n” can then be simultaneously transmitted upstream over the fiber optic cable, and passed through the photodiode for optical/electrical conversion and transmission to an upstream point, according to “fn”. For downstream communications, a single transmitter and a single wavelength ? can be used to transmit all fn signals.

Abstract: There is provided a customer premises optical network unit (ONU) capable of reading management signals and of outputting data through an external node by using I2C serial interfaces. In the ONU, an ONU functioning section has another serial signal terminal and is connected with a first management processing section through a sub-serial transmission path. The first management processing section is also connected with a MSA interface module through an additional monitoring signal transmission path and a monitoring signal transmission path. The monitoring signal transmission path on the side of the MSA interface module is connected with a sub-I/F section. A part of management signals set in an OAM layer of a signal transmitted between an OLT and the ONU may be outputted to an external node by using the first management processing section, the additional monitoring signal transmission path and the monitoring signal transmission path.

Abstract: Methods and systems are provided that prevent buffer overflow in multibus systems. In one aspect, a method for controlling the flow of data in a multibus system includes, for each node having an associated broadcast bus in the multibus system, generating status information regarding available data storage space of each receive buffer of the node. The method includes broadcasting the status information to the other nodes connected to the broadcast bus and collecting status information regarding the available storage space of receive buffers of the other nodes connected to the broadcast bus. The method also includes determining whether or not to send data from the node to at least one of the other nodes over the broadcast bus based on the collected status information.

Abstract: An optical line terminal includes an optical network interface having an optical receiver unit to convert an optical signal received from an optical network unit into an electrical signal and output a direct current bias monitoring signal and an error code detector to detect an error code in the electrical signal to output an error code indication signal, a storage to store therein a direct current bias table indicating a direct current bias corresponding to a direct current bias control parameter of the optical network units and a dynamic band allocation information table indicating communication time slot information allotted to each optical network unit and a control unit to receive the direct current bias monitoring signal and the error code indication signal and supply the direct current bias control signal to the optical receiver unit to thereby form one feedback circuit together with the optical network interface.

Abstract: A fiber distribution device includes a swing frame chassis pivotally mounted to a support structure. At least a first optical splitter module is mounted to the swing frame chassis. Pigtails having connectorized ends are carried by the swing frame chassis and have portions that are routed generally vertically on the swing frame chassis. An optical termination field includes fiber optic adapters carried by the swing frame chassis. The fiber optic adapters are configured to receive the connectorized ends of the pigtails.

Abstract: In a passive optical network, a downstream transmission rate from an OLT to multiple ONTs can be optimized by matching a transmission scheme for frames addressed to a channel to the downstream transmission characteristics of the channel. An FEC coding can be made channel dependent so that channels with low error rates can use minimal protection, and therefore minimal overhead, while channels with high input bit error rates can use the level of FEC coding required to produce a desired output bit error rate.

Abstract: Methods and apparatuses to provide an “Open access” service model using wavelength division multiplexing (“WDM”) passive optical networks (“PONs”) are described. A cross-connect is used to supply a first set of optical signals corresponding to a first service provider and a second set of optical signals corresponding to a second service provider to a WDM multiplexer/demultiplexer. The WDM multiplexer/de-multiplexer is used to multiplex and transmit the first set and the second set to a remote location. Another WDM multiplexer/de-multiplexer at the remote location is used to de-multiplex the first set and the second set. The first set may be supplied to a first user and the second set may be supplied to a second user. Transceivers coupled to the cross-connect may be used to generate the optical signals. For one embodiment, the transceivers include a wavelength-locked light source. For one embodiment, the transceivers are alike.

Abstract: An optical network unit useful in a passive optical network has capability for automatic shutdown upon detection of a malfunction, thereby protecting the integrity of upstream data transmitted in the network. The unit detects the generation of upstream light during intervals in which transmission is not authorized. In response, the light source of the unit is deactivated to prevent collisions with upstream data from other optical network units in the network.

Abstract: An apparatus comprising a frame alignment processor coupled to a receiver, wherein the frame alignment processor is configured to align a first frame and a second frame in the receiver by matching a first synchronization (sync) pattern predicted using a first sync field in the first frame with a second sync pattern obtained from a second sync field in the second frame. Included is an apparatus comprising at least one component configured to implement a method comprising receiving a first frame, subsequently receiving a second frame that was transmitted after the first frame, predicting a first sync pattern from a first sync field in the first frame, obtaining a second sync pattern from a second sync field in the second frame, and determining that the first frame and the second frame are aligned when the first sync pattern matches the second sync pattern.

Abstract: Technologies are generally described for substantially maximizing capacity in a wavelength division multiplexing (WDM) passive optical network (PON). An “achievable rate region” may be defined as a set containing admissible traffic rates of a given WDM PON system such that a volume of an achievable rate region is proportional to a capacity of the network. Deriving the achievable rate region for a particular network, decisions may be made whether incoming traffic rate can or cannot be achieved for that network. Moreover, the achievable rate region may be used to construct a WDM PON utilizing a minimum number of wavelengths, a minimum number of lasers with narrowest tuning ranges, and a minimum number of receivers, thereby reducing a capital expenditure in building the PON system.

Abstract: A system and method for handling accesses by nodes connected to a ring network, using time division multiplexing (TDM). The system includes: nodes capable of receiving only an optical signal of a wavelength or positional space allocated to the node, and of transmitting optical signals of wavelengths allocated to other nodes; and a ring network that performs TDM transmission of optical signals. The ring network has slots for transmitting optical signals of individual wavelengths. Information indicates whether an optical signal to be transmitted exists in each of the slots. Nodes include means for updating the information indicating that the optical signal exists and determining means for updating the information and determining, on the basis of the information, whether to transmit the optical signal.

Abstract: Methods and apparatus are described for “Smart” RF over Glass (RFoG) CPE Unit with Seamless PON Upgrade Capability. A method includes operating a customer premises equipment device including transporting upstream cable return services with a laser; and switching a drive source for the upstream laser from an analog driver to a digital driver by using a managed electrical switch to reuse a wavelength of the laser. An apparatus includes a customer premises equipment device including a laser for transporting upstream cable return services; and a managed electrical switch coupled to the laser that is used to switch a drive source for the upstream laser to reuse a wavelength of the laser.

Abstract: ONU 2A for P-P includes a signal-type discriminating unit 22A that discriminates whether a type of a downstream signal transmitted from OLT is for the P-P or not, and outputs an enable/disable control signal that controls an optical transmitter to an enable state or a disable state, and a control unit 21 that controls the optical transmitter to the enable state or the disable state according to the enable/disable control signal, wherein the signal-type discriminating unit 22A outputs to the control unit 21 a disable control signal that controls the optical transmitter to the disable state under an initial state before the type of the downstream signal is discriminated, and outputs to the control unit 21 an enable control signal that controls the optical transmitter to the enable state after the downstream signal is discriminated to be for the P-P.

Abstract: An OLT, which is one of the embodiments of the present invention, is provided with: an allocation request receiving unit that receives a bandwidth allocation request from each of 1G-ONUs and each of 10G-ONUs; an allocation execution unit that allocates to each of the ONUs a time slot for data transmission in accordance with an allocation rule based on fairness in time allocation or an allocation rule based on fairness in throughput allocation; and an allocation result notification unit that notifies each of the ONUs of information regarding the time slot.

Abstract: It is necessary to completely remove the overlapping of signals between plural PONs in order to make the PONs coexist. Accordingly, it is required to share or intensively manage bandwidth use conditions over an optical fiber that serves as a common band between plural systems. Therefore, transmission clocks should be synchronized with high accuracy between the plural systems. A reference clock is provided from an external device or a representative OLT to the entire systems to perform clock synchronization between the plural systems, so that the overall systems are synchronized by synchronizing each OLT with the reference clock. A hierarchical management method is selected that manages ONUs under the control of each OLT by managing band use information arranged for each OLT with respect to an external device or a representative OLT for sharing of bandwidth use conditions between plural systems.

Abstract: The present invention is to provide an optical access network in which a remote unit receives an optical burst signal. A central unit (OLT) transmits a DC-balanced optical continuous signal including packets having identification information for identifying each remote unit (ONU) to an optical switching module (OSM). The optical switching module (OSM) receives the DC-balanced optical continuous signal from the central unit (OLT), optically switches the packets based on the identification information, and transmits a DC-balanced optical burst signal including the packets to the remote unit (ONU). The remote unit (ONU) receives the DC-balanced optical burst signal and acquires the packets transmitted to the remote unit (ONU).

Abstract: An OLT allocates a bandwidth budget and assigns upstream transmission order by receiving upstream transmission requests from a plurality of ONUs. Each ONU's request includes a requested guaranteed bandwidth and a requested best effort bandwidth. Each ONU has respective first and second attribute values. One attribute is given allocation priority over the other attribute. One attribute is given scheduling priority over the other attribute. Within each attribute, an allocation rank and a transmission rank is assigned to the possible attribute values. The bandwidth budget is allocated in accordance with the allocation priority and ranks. The upstream transmissions are scheduled in accordance with the scheduling priority and ranks.

Abstract: A passive optical network couples a WDM optical line terminal (“OLT”) to WDM optical network units (“ONUs”). The WDM OLT includes an optical transmitter array with coherent transmitters to generate downstream WDM signals encoded using phase modulation, an optical receiver array with direct detection photo-detectors to receive upstream WDM signals encoded with amplitude modulation, and an optical diplexer optically coupled to the optical transmitter array and the optical receiver array. The WDM ONU includes a tunable optical transmitter having a first tunable laser source coupled to generate a selectable upstream carrier wavelength and direct amplitude modulation circuitry coupled to amplitude modulate the first tunable laser source and a tunable optical receiver having coherent detection circuitry to demodulate phase information from the downstream WDM signals and a second tunable laser source operated as a local oscillator and coupled to tune to a selectable downstream carrier wavelength.

Abstract: A transmission speed of a protection (backup) line using 1G-OLT unit and 1G-ONU unit is set to be lower than a transmission speed of a working (primary) line using 10G-OLT unit and 10G-ONU unit. A priority and band of each communication service in ONU are preset individually and separately every LLID for a working (primary) line and a protection (backup) line. When bands are allocated to the protection (backup) line, the band allocation is performed so as to secure a minimum number of bands of each communication service. A monitoring controller refers to a predetermined band information table according to an operation state of the working (primary) line or the protection (backup) line with respect to a downstream signal packet.

Abstract: A network of global coverage, scalable to hundreds of petabits per second, comprises bufferless switch units each of dimension n×n, n>1, arranged in a matrix of ? columns and ? rows, ?>1, interconnecting a maximum of ?×n edge nodes. Each edge node has ? upstream channels to ? switch units in ? different columns and ? downstream channels from ? switch units in ? different rows. All upstream channels to a switch unit are time-locked to the switch unit, thus enabling coherent switching at the switch unit. The switch units are preferably fast-switching optical nodes. Alternatively, the switch units may comprise fast-switching optical nodes each of dimension m×m, arranged in a first ?×? matrix, and latent space switches each of dimension n×n, n>1, arranged in a second ?×? matrix, ?>1, where ?×m=?×n. An edge node time locks to each optical node and each latent space switch to which it connects.

Abstract: Techniques and a control architecture (apparatus and logic) are provided for an adaptive hybrid DWDM-aware computation scheme. The architecture is one that is a hybrid of a centralized control scheme and a distributed control scheme that performs adaptive physical impairment computations for an optical network. A central control server is connected to multiple client control devices each of which resides in a node in a dense wavelength division multiplexed (DWDM) optical network, wherein each client control device is part of an optical control plane associated with the optical network. The control server obtains data for path route analysis from the client control devices.

Abstract: An optical access system capable of avoiding cutoffs or interruption in the periodically transmitted signals that occur during the ranging time is provided. A first method to avoid signal cutoffs is to stop periodic transmit signals at the transmitter during the ranging period, and transmit all the periodic transmit signals together when the ranging ends, and buffer the signals at the receiver to prepare for ranging. A second method is to fix definite periods ahead of time for performing ranging, then cluster the multiple periodic transmit signals together in sets at the transmitter and send them, and then disassemble those sets back into signals at the receiver. The transmitting and receiving is then controlled so that the transmit periods do not overlap with the ranging periods. In this way an optical access system is provided that can send and receive signals requiring periodic transmissions without interruption even during ranging operation.

Abstract: A method, system and apparatus for managing alarms in a Long Reach Passive Optical Network (LR-PON) system are disclosed. The method includes: obtaining a PON signal from an Optical Line Terminal (OLT) or an Optical Network Unit (ONU) on one side; checking whether the obtained PON signal fails; and notifying the ONU or the OLT on the other side if the PON signal fails. The method, system and apparatus under the present invention monitor the LR-PON transmission quality and process various alarm indications raised in the LR-PON signal monitoring.

Abstract: A subscriber terminal connected to a central-office unit in an optical communication network includes a variable optical attenuator for attenuating an optical signal received from the central-office unit; an optical-electric converter for converting the optical signal received via the attenuator to a corresponding electric signal; a clock extractor for extracting a clock from the electric signal and producing a clock extraction information signal representing whether or not the clock is extracted stably; and a terminal controller. The controller includes a clock extraction decider for determining whether or not the extractor stably extracts the clock on the basis of the information signal, a receiving level adjuster for setting an attenuation value to a value between a minimum and a maximum value, and an attenuation controller for setting the attenuation amount for the attenuator to the set attenuation value.

Abstract: An optical network component, architecture and method for a wavelength division multiplexed passive optical network includes a band coupler configured to demultiplex first and second wavelength division multiplexed content transmitted from an optical line terminal into a first band signal and a second band signal. An arrayed wavelength grating is configured to receive the first band signal and to further demultiplex the first band signal into different wavelengths to provide a plurality of wavelength signals. An optical splitter is configured to split the second band signal into sub-signals and multiplex the sub-signals with each of the wavelength signals such that the first and second wavelength division multiplexed content is provided on a single wavelength to a user.

Abstract: An optical line terminal connecting with numbers of optical network units comprises a control unit which controls each optical network unit to make it operate in a first mode in which transmission and reception of control messages and data are possible or in a second mode in which the transmission and reception of control messages are possible but the transmission of data is impossible, according to a communication permission request transmitted from an optical network unit and based on a preset maximum number of optical network units permitted to execute upstream communication from the optical network unit to the optical line terminal.

Abstract: A system, an unbundling optical line terminal (OLT), and a method are described herein that allow at least two service providers (SPs) to use individual fibers of an optical distribution network (ODN). In one embodiment, the unbundling OLT includes one or more wavelength division multiplexing-passive optical network (WDM-PON) line cards and one or more SP uplink cards that enable multiple SPs to each utilize one uplink port to access individual wavelengths of one or more passive optical networks (PONs). In another embodiment, the unbundling OLT includes one or more point-to-point line (p2p) line cards (e.g., p2p fiber Ethernet line cards) and one or more SP uplink cards that enable multiple SPs to each utilize one uplink port to access one or more individual fibers.

Abstract: A passive optical network is provided, which includes an optical central office connected to a line termination device by a branch of the network including a passive amplification medium. The central office is adapted to send/receive a first data optical signal and has a first amplifier for sending a second amplification optical signal. The second signal exciting the amplification medium to amplify the optical power of an optical signal. The line termination device is adapted to receive the first optical signal, modulate the second amplification optical signal; and inject the modulated second signal into the network.

Abstract: A wireless communication network architecture 100 is provided. The wireless communication network architecture consists of multiple fiber optic rings 110, 120, 130 and employs a Radio over Fiber (RoF) network. Each of these fiber optic rings is constructed using an optical fiber on a segment 105, 115, 125 formed by dividing a path. Each fiber optic ring includes a number of remote antenna units (RAUs) 181-184, 191-194. Each RAU 4 is integrated into a corresponding Add/Drop Multiplexer (ADM) 186-189, 196-199 and each ADM is further connected to a base station.

Abstract: A method, apparatus and system for bearing Internet Protocol (IP) packets over a Passive Optical Network (PON) are disclosed. The method includes obtaining an IP packet, converting the IP packet into a Gigabit PON Encapsulation Method (GEM) frame. The method further includes performing a Gigabit PON Transmission Convergence (GTC) framing on the GEM frame to obtain a GTC frame and performing a PON physical layer processing on the GTC frame.

Abstract: A first node receives a first phase modulated optical signal at a first wavelength from a master node. The first node also transmits a first amplitude modulated optical signal to the master node at the first wavelength using a portion of the first phase modulated optical signal as a light source.

Abstract: A Cable Television optical fiber communication system is disclosed, comprises a provider end, plural optical signal transmission devices and plural user ends, each optical signal transmission device is provided between the provider end and the user ends and has an light splitting element, a RF receive module, and a RF return module. The light splitting element is connected to the provider end via an optical transmission wire and is served to bi-directionally transfer a laser beam having a signal between the provider end and the user ends. The RF receive module is served to transfer a first signal of the provider end to the user ends. The RF return module emits a laser beam having a second signal to the provider end only when an analog return signal is emitted from the user end.

Abstract: Transmitting and receiving data includes a process of transferring data over a coaxial network between an optical node and a plurality of cable modems of a hybrid fiber-coaxial cable network. A data transfer system which sends and receives data over a coaxial network located at an optical node of a hybrid fiber-coaxial cable network.

Abstract: The present invention relates to a wavelength-division multiplexed passive optical network (WDM-PON) for reducing degradation in noise characteristic of a wavelength-locked Fabry-Perot Laser Diode (F-P LD).

Abstract: A protocol configuration method for use by a substation to be coupled to a main station in an optical access network is described.

Abstract: Techniques, apparatus and systems for optical communications, including fiber ring networks with protection switching to maintain optical communications when an optical failure occurs and to automatically revert to normal operation when the optical failure is corrected, fiber ring networks that provide a circulating optical probe signal at an optical probe wavelength within the gain spectral range of optical amplifiers used in a fiber ring network to detect an optical failure, and fiber ring networks that support broadcast-and-select optical WDM signals carrying communication traffic to the optical ring nodes without regeneration at each optical ring node and one or more overlaid in-band node-to-node optical signals carrying communication traffic with regeneration at each node.

Abstract: Provided are a semiconductor optical amplifier and an optical signal processing method using the same. The reflective semiconductor optical amplifier includes: an optical signal amplification region operating to allow a downward optical signal incident from the external to obtain a gain; and an optical signal modulation region connected to the optical signal amplification region and generating a modulated optical signal. The downward optical signal is amplified through a cross gain modulation using the modulated optical signal and is outputted as an upward optical signal.

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 equipment which is utilized in a power line communication (PLC) system utilizing a hybrid fiber coax (HFC) which includes a PLC optical network unit, a PLC trunk bridge amplifier, a PLC distribution amplifier, and a PLC coupling device. In this instance, the PLC optical network unit does not require a PLC protocol conversion of an Ethernet signal by a cable modem and a PLC modem in each subscriber location, and enables a PLC communication between the each subscriber location and a communication terminal utilizing a PLC Ethernet signal as is, by receiving an optical signal from an optical transmitter via an optical fiber, converting the optical signal into the PLC Ethernet signal corresponding to a predetermined PLC protocol, and transmitting the PLC Ethernet signal to at least one subscriber location via a coaxial cable.

Abstract: Upstream data handling in a digital Data Over Cable Service Interface Specification (DOCSIS) passive optical network (DPON). Embodiments include receiving at a headend, in an upstream path over an optical network, a plurality of digitized and serialized DPON upstream packets respectively distributed in a time division multiplexed fashion, wherein each DPON upstream packet includes a header, a trailer and a payload, monitoring the optical network for energy in the upstream path, including energy associated with a header and a trailer of respective DPON upstream packets, controlling a bit stuffer that adds bits to the upstream path to (1) stop adding bits to the upstream path when energy is detected in the upstream path and (2) resume adding bits to the upstream path after an end of a trailer of a given DPON upstream packet has been detected, and removing the header and the trailer of the respective DPON upstream packets.

Abstract: In one embodiment, a method for providing wireless communications utilizing a passive optical network (PON) is disclosed. The method includes receiving, at a PON, downstream packets from a base station destined for a mobile station, and transmitting the downstream packets to wireless transceivers associated with PON. The method also includes receiving, at the first wireless transceiver communicatively coupled to a first optical network terminal (ONT), the downstream packets from the first ONT and transmitting a first wireless signal comprising the downstream packets to a first cell. The method also includes receiving, at a second wireless transceiver communicatively coupled to a second ONT, the downstream packets from the second ONT and transmitting a second wireless signal comprising the downstream packets to a second cell.

Abstract: Dynamic optical wavebands are disclosed that allow a plurality of user streams having a common destination node to be positioned in a substantially adjacent non-overlapping manner on a spectrum for treatment as a routable entity. Each waveband has an associated center wavelength and spectral extent. The plurality of user streams can optionally be encrypted using a corresponding cipher. Wavebands that are received by a network node are filtered so that individual wavebands can be isolated, if necessary. For example, individual wavebands can be switched to an appropriate output node for forwarding in the optical network. In addition, the center wavelength and spectral extent of a waveband can be converted, if necessary, to position the waveband substantially spectrally adjacent to another waveband sharing a common path portion. In this manner, the substantially spectrally adjacent wavebands can be treated as an aggregated waveband for the common portion of a path.

Abstract: A fiber optic network transmits data between a hub node and a plurality of local nodes connected by at least one unidirectional fiber ring. Downstream data streams are carried on wavelength-division-multiplexed optical carriers from the hub node to the local nodes. An optical carrier corresponding to a specific wavelength carries downstream data streams to a specific local node. Downstream data streams are multiplexed onto an optical carrier via orthogonal frequency division multiplexing. A parallel signal detector in each local node detects all downstream optical carriers. A signal processing module demultiplexes the data stream from the optical carrier having the specific wavelength corresponding to the local node. An upstream data stream is multiplexed via orthogonal frequency division multiplexing onto an upstream optical carrier having the same specific wavelength and transmitted from the local node to the hub node. Upstream data awaiting transmission is allocated to specific subcarriers and time slots.

Abstract: A base station is provided for communicating data to a mobile terminal unit by means of at least one antenna unit, wherein the at least one antenna unit is linked to the base station by means of at least one optical fiber and the at least one antenna unit is operable to communicate wirelessly with the mobile terminal unit. The base station comprises an optical transmitter for transmitting modulated data signals to the at least one antenna unit for wireless transmission, an optical receiver for receiving modulated data signals forwarded by the at least one antenna unit and a demodulator for demodulating received modulated data signals.

Abstract: A distributed resources sharing method using weighting factors of sub-domains in an optical network includes connecting working paths to an optical network according to a request of a subscriber, and calculating weighting factors for measurement of concentration of the sub-domains including the working paths by using information on connected working paths. The method also includes setting up the backup paths by using the weighting factors, and allocating resources in response to connection request at the time of setting up the backup path and sharing the allocated resources. With this method, it is possible to prevent a waste of idle resources caused from concentration of allocated resources. In addition, since the information of the idle resources in the network can be sensed at the time of selecting the backup paths by using a weight factor, the shared resources can be distributed, thereby maximizing efficiency of the resources.