Abstract: A passive optical network is upgraded by a subsystem PON2 for additional high speed communication. The additional subsystem PON2 enables independent high speed communication between a new type of optical network terminations with second downstream time division multiplex signals and second upstream multiplex burst signals via additional upstream and downstream channels.

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: An OLT includes a first transmitter and receiver unit for transmitting and receiving signals with ONUs, a first communication control timer, a measurement unit for measuring a round trip time (RTT) between the OLT and each of ONUs, an advance notice time generation unit for generating an advance notice time signal by adding a predetermined time to a time information that indicates a time in the first communication control timer in response to a first time reference pulse, and a unit for controlling the first transmitter and receiver unit to transmit the generated advance notice time signal to each of the ONUs, and to transmit signals indicating measured RTT/2 to the respective ones of the ONUs.

Abstract: An HDMI optical transceiver comprises an optical bench, at least one light emitter disposed on the optical bench, at least one first fiber assembly, at least one photodetector disposed on the optical bench and at least one second fiber assembly. The optical bench has a surface, at least one first groove recessed from the surface and at least one second groove recessed from the surface. The light emitter has a light-emitting surface. The first fiber assembly is disposed at the first groove of the optical bench and comprises a first sleeve fixed at the first groove and a first optical fiber which is disposed in the first sleeve and aligned with the light-emitting surface. The photodetector has a light-receiving surface. The second fiber assembly is disposed at the second groove of the optical bench and comprises a second sleeve fixed at the second groove and a second optical fiber which is disposed in the second sleeve and aligned with the light-receiving surface.

Abstract: In the present invention, a receiving unit using a voltage-controlled oscillator, and the like are allowed to compensate for the frequency characteristics of the voltage-controlled oscillator resulting from temperature change, without adding a capacitive element for temperature compensation.

Abstract: A general object of the present invention is to provide an optical communication system in which an optical transmission power of an optical communication apparatus is controlled to be a required minimum power that apparatuses of all subscribers in the optical communication system meet a prescribed error rate. An optical line terminating apparatus (OLT) transmits data to multiple optical network apparatuses (ONUs) at an optical intensity calculated based on information acquired from the multiple ONUs, which is related to optical intensities of signals that the multiple ONUs receive from the OLT, the optical intensity being calculated so that a minimum optical intensity of the optical intensities of the signals is greater than a predetermined value.

Abstract: An object of the present invention is to improve the accuracy of bandwidth control by an optical line terminal 1 by preventing an optical network unit 2 from performing upstream transmission of an amount of data that is not expected by the optical line terminal 1. The optical network unit 2 of the present invention is an optical network unit in a PON system, which is capable of performing bidirectional optical communication with the optical line terminal 1 through a passive light-splitting node 6, and which performs upstream transmission of a FEC frame including a variable length frame to the optical line terminal 1. The optical network unit 2 includes a grant processing unit 207 that determines whether an amount of allocation specified in a grant G1 which is a report request is one unit amount of data (one FCW) of the FEC frame; and a frame transmitting unit 206 that transmits only a report R to the optical line terminal 1 if a result of the determination is affirmative.

Abstract: Provided is a passive optical network (PON) based on a reflective semiconductor optical amplifier (RSOA). In the PON, seed-light-injection RSOAs are used in an optical line terminal (OLT) to achieve the color-less management of the wavelengths of OLT optic sources, and wavelength reuse RSOAs are used to achieve the color-less management of the wavelengths of ONTs. Therefore, problems related to ONT wavelength management can be eliminated by the wavelength reuse RSOAs, and problems related to OLT wavelength management can be eliminated by the seed-light-injection RSOAs.

Abstract: The present disclosure discloses a passive optical network (PON) user terminal comprising a passive optical network interface unit (PONIU) having access to a PON system, a service data distribution unit (SDDU) connected to the PONIU for distributing service data, a plurality of service processing units (SPUs) for receiving and accordingly processing the service data distributed by the SDDU, a power source for providing power to the above units, and a power supply control unit (PSCU) for controlling the activating/deactivating of the energy-saving power supply to the SPUs, the SDDU, and the PONIU. The present disclosure further provides a method for controlling the PON power supply and for reporting the power supply state. The present disclosure allows control of the energy usage of the PON user terminal to save power when a service in the PON user terminal is not used or when the user terminal uses a backup power source to supply power.

Abstract: According to one embodiment of the present invention, a wavelength-shifted dynamic intelligent bidirectional access optical system utilizes key optical elements such as: a quantum dot enabled semiconductor optical amplifier, a phase modulator and an intensity modulator to provide upstream optical signals. These key optical elements reduce the Rayleigh backscattering effect on the transmission of optical signals. Reduced Rayleigh backscattering effect enables a longer-reach access network topology (more than any other current access network topology) between a subscriber unit and a super node (e.g., many local nodes collapsed into one super node). Such a longer-reach access network topology eliminates operational costs and capital costs related to a vast array of middle equipment such as routers and switches, which would otherwise be needed between super nodes and many remote nodes.

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: A dynamic bandwidth allocation method of an Ethernet passive optical network, comprises a predictor and a rule of QoS-promoted dynamic bandwidth allocation (PQ-DBA); the predictor predicts a client behavior and numbers of various kinds of packets by using a pipeline scheduling predictor consisted of a pipelined recurrent neural network (PRNN), and a learning rule of the extended recursive least squares (ERLS); the present invention establishes a better QoS traffic management for the OLT-allocated ONU bandwidth and client packets sent by priority.

Abstract: A network for delivering optical power over an optical conduit includes at least one optical power source delivering optical power to multiple outlet power subsystems the subsystem managing demands for power from the multiple outlet sinks.

Abstract: A method for accessing a Passive Optical Network (PON) is disclosed. The method includes: obtaining a first distance parameter of an Optical Network Unit (ONU), where the first distance parameter indicates the location of the ONU relative to an Optical Line Termination (OLT); receiving an ONU information request message delivered by the OLT, and returning an ONU information response message to the OLT when a second distance parameter carried in the ONU information request message corresponds to the first distance parameter; and receiving a ranging request message, where the ranging request message is delivered by the OLT according to the ONU information response message, returning a ranging response message as a basis for the OLT to obtain an Equalization Delay (EQD) value of the ONU, and connecting the ONU to the PON according to the EQD value. An ONU, an OLT, and a PON are also disclosed.

Abstract: A time division multiplex (TDM)/wavelength division multiple access (WDMA) passive optical network (PON) device includes a base station terminal, a wavelength splitter, and a subscriber terminal optical transceiver. The base station terminal includes a transmitter, an optical circulator transmitting the optical signals output from the transmitter to an optical distribution network, and a receiver demultiplexing wavelength division multiplexed upstream signals from the optical distribution network through the optical circulator. The wavelength splitter splits the downstream signals from the base station terminal to subscriber ports corresponding to wavelengths and multiplexes the optical signals received from each of the subscriber ports to the base station terminal. The subscriber terminal optical transceiver receives the downstream signals from the wavelength splitter and reuses the received downstream signals as optical sources for upstream signals.

Abstract: A system for providing bi-directional RF services over a point-to-multipoint Passive Optical Network (PON). A system that can transport upstream RF signals generated by devices such as a set top box or a cable modem, through a passive Optical Network while simultaneously supporting downstream RF video and bi-directional base-band services on the PON.

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.

Abstract: Provided is an apparatus for implementing an electro-optical cable distribution network in which a coaxial cable is replaced with an optical cable in order to provide a service integrating broadcast data and communication data by solving a frequency constraint problem in a cable television (CATV) network employing a conventional hybrid-fiber coaxial (HFC) network architecture. The apparatus includes an optical network unit (ONU) which converts a downstream signal received from a system operator (SO) into an optical signal and transmits the optical signal to an optical cable; and an optical cable modem which receives the optical downstream signal from the ONU and converts the received signal into an electrical signal. In addition, the ONU and the optical cable modem control signal quality of an optical path.

Abstract: A passive optical network (PON) system comprising a plurality of optical network units (ONUs) having one downstream receiver and one upstream transmitter, an optical line terminal (OLT) having a downstream transmitter and a plurality of upstream receivers, wherein each upstream receiver is associated with a subset of the ONUs, and an optical distribution network (ODN) that connects the OLT to the ONUs is disclosed. An OLT for a PON, comprising a downstream transmitter, and a plurality of upstream receivers, wherein a downstream transmitter bandwidth is greater than each upstream receiver bandwidth is also disclosed. A network component comprising a processor configured to implement a method comprising determining a downstream bandwidth and an upstream bandwidth for a PON, and increasing a number of upstream channels per downstream channel for the PON when asymmetry between the downstream bandwidth and the upstream bandwidth is greater than a threshold amount is also disclosed.

Abstract: A method, a computer readable medium, and a system for discovering an Optical Network Terminal (ONT) in a Dense Wave Division Multiplex (DWDM) hybrid Passive Optical Network (PON) Line Terminal (LT), comprises implementing, by an Optical Line Termination (OLT), a ranging procedure on at least one downstream link, wherein the OLT is communicably coupled to the ONT, discovering at least one new ONT, by the OLT, on the at least one downstream link based on the ranging procedure, discovering an unranged ONT, by the OLT, during the ranging procedure, and determining, by the OLT, that the unranged ONT resides on the at least one downstream link.

Abstract: In general, techniques are described for inline packet replication in network devices. A network device referred to as an optical line terminal (OLT) may implement the techniques. The OLT comprises a customer interface that supports different logical interfaces to which couple a plurality of optical network terminals (ONTs) and a network interface that receives a data unit. The OLT further comprises a conversion unit, such as a media access control (MAC) module, located in a data path of the optical line terminal that determines whether the received data unit is a candidate for replication. The conversion unit includes an inline packet processing module that performs replication to generate at least one copy of the data unit based on the determination that the received packet is a candidate for packet replication. The customer interface outputs the at least one copy of the data unit to the ONTs.

Abstract: A optical switch and switching system is provided for effecting a switchover from a first optical fiber to a second optical fiber includes a first, large scale switching component and a second, small scale switching component. The first, large scale switching component is configured to establish a cross connect between the second optical fiber and the second, small scale switching component. The second, small scale switching component may then be configured to select the cross connect following establishment of the cross connect, thereby ensuring rapid switchover from the first fiber to the second fiber, regardless of the speed of the first large scale switching component.

Abstract: In a PON system by WDM, IP broadcast can be received without oppressing a band used by a user for Internet communication. An OLT provides a first wavelength received in common by respective ONUs and plural second wavelengths by which the OLT and the respective ONUs perform communication individually. With respect to signals in the downstream direction, each of the OLTs includes a transmitter to transmit the first wavelength and plural transmitters to transmit the second wavelengths used for the individual communication with the respective ONUs. Each of the ONUs includes a receiver to receive the first wavelength and a receiver to receive the second wavelength used in the ONU itself. The OLT transmits data of the IP broadcast by the first wavelength and transmits individual data of each of the ONUs by the second wavelength corresponding to the ONU.

Abstract: A passive optical network system, a line coding method and an optical network unit are described. The optical network unit comprises a downlink optical receiver configured to receive a first portion of a downstream data signal, and an uplink optical remodulator configured to receive a second portion of the downstream data signal and remodulate it to generate a return-to-zero line coded upstream data signal. The downstream data signal may be inverse-return-to-zero line coded.

Abstract: In accordance with the teachings of the present invention, a system and method for transmitting upstream traffic in an optical network is provided. In a particular embodiment, the method includes transmitting upstream traffic at a first wavelength from a first downstream terminal to a distribution node and transmitting upstream traffic at a second wavelength from a second downstream terminal to the distribution node. The method also includes combining the upstream traffic in the first wavelength and the upstream traffic in the second wavelength at a coupler in the distribution node without multiplexing the upstream traffic in the first wavelength and the upstream traffic in the second wavelength. The method also includes forwarding the combined traffic from the distribution node to a single upstream terminal.

Abstract: This is a method for use in architecting low cost networks using a thin optical transport layer. A long reach hot pluggable interface is inserted onto an electrical switch resulting in a standardization of the optical layer. Standardized parts like the long reach hot pluggable interfaces and standard control planes form the logic that connects components of the low cost optical layer. After the components are in place, provisioning is done at end points only. This ensures an automatic and fast turn-up capacity without the need to visit intermediate sites in the network.

Abstract: A visible light multiplex communication system, and more particularly, a visible light multiplex communication system in which identification (ID) information and data information can be simultaneously transmitted and received to and from a server and a plurality of clients by using visible light, is disclosed. Visible light communication can be smoothly performed in a state where visible light ID communication and visible light data communication do not interfere with each other in the same space. In addition, data can be efficiently transmitted and received to and from a plurality of ID clients and a plurality of data clients by using visible light. In addition, visible light ID communication and visible light data communication can be efficiently performed in a state where interference between a plurality of clients using different protocols does not occur in the same place.

Abstract: A method for operating PON (passive optical network) user terminal and a PON user terminal equipment, when there is only few data service request in the PON, the PON user terminal operates in power saving manner which maintains low speed connection, the method comprises: a judgment condition that the PON user terminal changes to power saving state is set; the PON user terminal determines whether its own state meet the judgment condition changing to power saving state, if so, it transmits a request to change to power saving state to the OLT (optical line terminal); after the PON user terminal receives the respond that the OLT has accepted the request, it controls parts of the modules therein to change to power saving state, and intermittently switch over between power saving state and normal state. The invention allows saving power under the condition that keeps the low speed service uninterrupted, in the meanwhile alleviates the pressure of ONU terminal thermal design.

Abstract: There is a need to recover an ONU from a sleep state for communication with the PON before a specified sleep cancel time in a short period of time without degrading the band use efficiency. An OLT manages an electric state of each ONU connected to a PON. When at least one ONU is in sleep mode, the OLT transmits a grant to allocate a band for a sleep cancel report to the ONU. When the sleep-mode ONU requires communication, the ONU transmits the sleep cancel report to the OLT using the band for the sleep cancel report. When receiving the sleep cancel report, the OLT changes the managed ONU to a normal state and resumes the communication with the PON.

Abstract: While continuously providing a service in an existing optical communication system, a service at another communication speed is realized at low cost. For this reason, a station-side optical network terminal apparatus is configured so that to one light-emitting unit connected are a first processing unit that performs a process to output an optical signal at one communication speed by the light-emitting unit and a second processing unit that performs a process to output an optical signal at another communication speed by the light-emitting unit.

Abstract: In order to be able to moderate the inclination of the PON burst reception characteristics and to improve the FEC effect, a first offset is used in a ranging window field, and a second offset, which is lower than the first offset value, is used in a burst data field other than the ranging window field.

Abstract: A method for enabling bidirectional data communication using a single optical carrier and a single laser source with the aid of an integrated, colorless demodulator and detector for frequency modulated signals, and a reflective modulator. A receiving optical system holds a technique for demodulation and detection of optical frequency modulated signals, enabling remodulation of the incoming signal to establish bidirectional communication with the transmitting optical system, without introducing a high penalty. A colorless demodulator and detector, which provides the functionality of a periodic filtering device for demodulation of the downstream, and also detection capability. The principle of operation of the CDD relies on the introduction of a comb transfer function with the help of a Semiconductor Optical Amplifier, by providing a reflected feedback signal to the CDD's active element.

Abstract: The present invention discloses methods for reducing power consumption in a PON while maintaining service continuity, the method including the steps of: providing an OLT operationally connected to at least one ONU; triggering a sleep request for at least one requesting ONU; upon receiving a sleep acknowledgement, activating a sleep mode for at least one requesting ONU according to a sleep period designated in the sleep request; and terminating the sleep mode according to the sleep period. Preferably, the sleep acknowledgement is transmitted from the OLT to the requesting ONU. Preferably, the sleep period is executed by a sleep command in the sleep acknowledgement. Preferably, the method further includes the step of: upon completion of the sleep period, transmitting buffered data traffic from the OLT to a sleeping ONU. Preferably, the step of transmitting is performed without the sleeping ONU being re-registered and without causing packet reordering.

Abstract: A WDM optical system includes first and second WDM's including an optical link therebetween. Each WDM includes circuitry for linking multiplexer and demultiplexer circuitry to a plurality of modular elements. The modular elements include a first set of modules for converting between native protocol media signals and common format signals. A second set of modules converts between the common format signals and optical signals at separate wavelengths for communication with the multiplexers and demultiplexers. A dual path transmit and receive optical link is provided between near and far end WDM's.

Abstract: Distributed CMTS device for a HFC CATV network serving multiple neighborhoods by multiple individual cables, in which the QAM modulators that provide data for the individual cables are divided between QAM modulators located at the cable plant, and remote QAM modulators ideally located at the fiber nodes. A basic set of CATV QAM data waveforms may be transmitted to the nodes using a first fiber, and a second set of IP/on-demand data may be transmitted to the nodes using an alternate fiber or alternate fiber frequency, and optionally other protocols such as Ethernet protocols. The nodes will extract the data specific to each neighborhood and inject this data into unused QAM channels, thus achieving improved data transmission rates through finer granularity. A computerized “virtual shelf” control system for this system is also disclosed. The system has high backward compatibility, and can be configured to mimic a conventional cable plant CMTS.

Abstract: An optical data transmission system having a hub, an optical router, and a plurality of optically pumped sources at a curb location, and a plurality of optical network units (ONUs). The ONUs generate and transmit respective data modulated pumping light to the curb location where it is received by the optically pumped sources, which convert it into the wavelength channels having predefined wavelength ranges assigned to respective ONUs. The optical router routes the wavelength channels for transmission to the hub.

Abstract: A system for providing bi-directional RF services over relating to a point-to-multipoint Passive Optical Network (PON).

Abstract: An optical system and method includes a source-free optical network unit coupled to an optical fiber for receiving an original carrier signal with downstream data over the optical fiber. The optical network unit includes a modulator configured to remodulate the original carrier signal with upstream data to produce an upstream data signal for transmission back down the optical fiber in a direction opposite to a direction in which that original carrier signal was received.

Abstract: Provided is an ONU that suppresses transmission of a useless multicast control message to a PON section and enables a communication bandwidth of the PON section to be effectively used. The ONU of the PON system has a multicast group management table that shows a correspondence between a multicast group identifier and an address of a user terminal participating in a multicast group. When the ONU receives a request message of participation in the multicast group from the user terminal, the ONU registers the correspondence between the multicast group identifier indicated by the received message and the user terminal address. A new received message is deleted without being sent to the OLT if another user terminal address is registered already, along with a correspondence with the same multicast group identifier, in the multicast group management table.

Abstract: System and method for data synchronization in Passive Optical Networks. According to an embodiment, the present invention provides a method for providing upstream data synchronization in an optical communication network. The method includes sending data from an Optical Network Unit. The data includes a first data frame, which includes a header sequence, a synchronization segment, and a data segment. The synchronization segment includes 66 bits, which includes a first number of bits having nonzero values and a second number of bits having a value of zero. The first number is different from the second number. The method further includes receiving at least the first data frame by an Optical Line Terminal. The method also includes processing the first data frame. The method additionally includes selecting a first segment of the first data frame, the first segment including 66 bits.

Abstract: A system for transporting signals through PON, including a device for transporting optical network signals and a device for transporting optical line signals, wherein: the device for transporting optical network signals is adapted to map upstream optical signals with a PON frame format to upstream optical channel data unit signals, to convert into upstream signals with an optical channel transport unit format, and to transport to the device for transporting optical line signals through OTN; and to perform corresponding downstream processing; the device for transporting optical line signals is adapted to convert the upstream signals into upstream optical channel data unit signals, to de-map to upstream optical signals with a PON frame format, and to transport to an optical line terminal; and to perform corresponding downstream processing. The invention further discloses relevant devices and methods.

Abstract: To achieve a station-side apparatus of a wavelength multiplexing PON system, which is capable of saving the wavelength resource through automatically carrying out allotment of the wavelength and the network address to reduce the complicated work for the setting, and through dynamically allotting the wavelength without fixing it in advance. It is a station-side apparatus (OLT) of a wavelength multiplexing PON system that comprises a plurality of in-home apparatuses (ONUs). The station-side apparatus is connected to the in-home apparatuses via transmission paths including an optical multiplexing distributor, and executes allotment of the wavelength in response to wavelength allotment requests from the in-home apparatuses. The station-side apparatus comprises a wavelength/network address allotting device that is provided with a DHCP server in advance, which dynamically allots wavelength and network address to the in-home apparatus in response to the wavelength allotment request from the in-home apparatus.

Abstract: A network interface apparatus comprises a bidirectional optical signal port, an optical diplexer connected to the bidirectional optical signal port, a first RF signal port (bidirectional), a second RF signal port, a first RF diplexer, and an RF splitter. The RF diplexer transmits a first received RF input signal from the first RF signal port to the optical diplexer to modulate an optical output signal transmitted by the optical diplexer to the optical signal port. The RF splitter receives from the optical diplexer an RF signal derived from an RF-modulated optical input signal received from the bidirectional optical signal port, transmits a first portion of the derived RF signal as a first RF output signal to the first RF signal port through the first RF diplexer, and transmits a second portion of the derived RF signal as a second RF output signal to the second RF signal port.

Abstract: The present invention discloses a method, device and system for managing information of an optical node in an optical distribution network, relates to management of information of an optical node in an optical distribution network, is capable of solving the problem of manual entry of information of an optical node being cumbersome, and is not limited by installation locations of the optical node. The method for managing information of an optical node in an optical distribution network includes: obtaining an identity code of an optical node; querying a pre-established optical node information table according to the identity code of the optical node, wherein the optical node information table comprises the identity code of the optical node and the installation location information of the optical node. The present invention is suitable for management of information of an optical node in an optical distribution network.

Abstract: This invention provides a method for upgrading the network rate of a Passive Optical Network (PON), which mainly includes: upgrading the optical fiber line rate of the central office device, and adapting, by the network terminal device, the working rate of the upstream/downstream line automatically to the optical fiber line rate of the central office device according to a downstream data flow transmitted from the central office device. Using the method of this invention, the network rate of the PON can be upgraded without replacing the network terminal and without a manual intervention.

Abstract: An optical access communication apparatus and an optical access communication system for the coexistence of two wideband PON systems without using an expensive optical device or module. A low-speed PON and a high-speed PON have a same upstream wavelength, and an OLT receives optical signals by a same optical receiver in the two systems, converts the optical signals into electric signals, amplifies the electric signals, branches the amplified electric signals, and processes the branched signals by clock and data recovery sections of bit rates corresponding to the two PON systems, thereby achieving an optical communication apparatus and an optical communication system for constructing a simple and low-cost triple-play service system of excellent transmission quality.

Abstract: In a light reception element such as an APD (Avalanche Photo Diode) used for receiving a high-speed and weak optical signal, it is possible to prevent the phenomenon of distortion of a signal inputted after a large-level light is received. A PON (Passive Optical Network) system includes an OLT (Optical Line Terminal) which can impartially and effectively transmit light reception data to each ONU (Optical Network Unit). According to a light reception amplitude received by each ONU, an inter-frame gap of an appropriate length is assigned for each ONU. The OLT includes a unit for measuring and accumulating the reception light amplitude and data on the inter-frame gap of an appropriate length decided in advance according to the characteristic of the light reception device and generates a grant value for assuring an inter-frame gap of an appropriate length by using the both information.

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: 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 problem to be solved in an optical communication system for carrying out bidirectional transmission between communication nodes by wavelength-division-multiplexed optical signals is that a plurality of optical add-drop multiplexers installed in the communication nodes are required for each transmission direction, and therefore, the communication cost is increased. An optical circulator or an optical coupler is arranged at an input/output port of the optical add-drop multiplexer and the wavelength-division-multiplexed optical signals are assembled for each transmission direction, whereby optical signals transmitted bidirectionally can be handled by one optical add-drop multiplexer.