Abstract: An optical communication system includes a plurality of Customer Premises Equipment (CPE) each having a reverse power supply and configured to transmit and receive data and provide power over a wire pair connected thereto. An optical network unit is formed as a plurality of communication ports. A respective communication port is configured to provide communications data service with a respective CPE by transmitting and receiving data therewith. A power management circuit is connected to the communication ports and configured to receive power provided by each reverse power supply at a respective CPE and manage power consumption in the ONU. A processor is configured to receive alarms generated by at least one of a CPE and ONU indicative of a power fault condition and process the alarms and discriminate between different power fault conditions.

Abstract: Methods and apparatus for line coding in a communications network are described. According to one embodiment of the invention, downstream communications traffic bits are received and mapped into downstream bit positions of a transmission structure. A pre-selected bit in each upstream bit positions of the transmission structure is provided to form a downstream transmission structure. A downstream optical signal carrying the downstream transmission structure is generated for transmission. Upstream communications traffic bits are also received and mapped into the upstream bit positions of the transmission structure to form an upstream transmission structure. An upstream optical signal carrying the upstream transmission structure is generated for transmission.

Abstract: A system for delivering multiple passive optical network services is disclosed. The system includes a first optical transmission service comprising a common wavelength pair routed from a source to each of a plurality of subscribers. The system further includes a second optical transmission service comprising a plurality of unique wavelength pairs, where each of the unique wavelength pairs is routed from the source to a subscriber among the plurality of subscribers. The system delivers the first optical transmission service and the second optical transmission service to the subscriber on a single optical fiber.

Abstract: An OLT comprising a processor configured to calculate a downstream bandwidth map that indicates an active period of time when the OLT is scheduled to transmit a data frame to an ONU, and generate a message comprising the downstream bandwidth map, and a transmitter coupled to the processor and configured to send the message to the ONU via a PON, wherein the message instructs the ONU to power off at least one ONU receive data processing unit outside the active period. Also disclosed is a computer program product comprising computer executable instructions stored on a non-transitory computer readable medium such that when executed by a processor cause an ONU to receive a message indicating an active period, wherein the active period indicates a scheduled period during which data communicated over a PON is relevant to the ONU and power down an ONU receive data processing unit outside the active period.

Abstract: An optical transmission system comprises a metropolitan core network operated in a wavelength division multiplexing mode and connected via metro connection devices to access connections to optical network terminals connected by means of a passive optical splitter. The metro connection devices contain regenerators and wavelength converters, so that data regeneration takes place between the network terminals and the central management and switching unit. This makes it possible to cover distances around 100 km.

Abstract: Novel tools and techniques providing for the robust wire-based plus wireless distribution of communications signals from a provider to multiple customer premises. Certain embodiments comprise one or more modular communications apparatuses which are located near to customer premises. The modular communications apparatuses features an enclosure which is, at least in part, transparent to radio frequencies. A modular communications apparatus also typically includes one or more communications radios or transmitter/receiver devices within the enclosure. The apparatus also includes at least one and possibly more than one antenna located within the enclosure along with wire or cable-based signal output apparatus.

Abstract: One or more devices of a network having asymmetric delay are configured to participate in time synchronization protocol sessions in which a client device synchronizes its local clock to a master device. In one example, a system includes an optical line terminal configured to receive a time synchronization protocol packet from a grandmaster clock and an optical network unit (ONU) configured to calculate a residence time of the time synchronization protocol packet, encode the residence time into the packet, and to forward the packet to a client device. Moreover, the system may participate in a plurality of time synchronization protocol sessions with a plurality of client devices, such that the client devices become synchronized in frequency and phase.

Abstract: A media distribution system for aircraft comprises a processor, an optical encoder/decoder, and an optical backbone. The processor is configured to retrieve digital media from an in-flight media node. The optical encoder/decoder is configured to optically encode the digital media. The optical backbone is configured to carry the encoded digital media between the optical encoder/decoder and a Li-Fi access point at a passenger seat location.

Abstract: A time synchronization method and a time synchronization device in a passive optical network (PON), and a PON are provided. The method includes receiving a synchronization packet sent after time synchronization of an optical line terminal (OLT) with a master clock (MC) is achieved, wherein the synchronization packet carries a timestamp TMt1i determined after the time synchronization of the OLT is achieved, adjusting a local clock according to the timestamp to achieve time synchronization of an optical network unit/optical network terminal (ONU/ONT) with the OLT, and after the time synchronization of the OLT is achieved, instructing an slave clock (SC) to perform time synchronization. A time synchronization device and a time synchronization system for implementing the method in a PON are further provided.

Abstract: There are provided a method of allocating upstream bandwidth resources and a method of transmitting upstream data in an orthogonal frequency division multiple access-open optical subscriber network. The method of allocating an upstream bandwidth resource according to an embodiment of the invention includes receiving queue status information from each optical network unit (ONU), and allocating an upstream bandwidth by providing to each ONU a 2-D upstream bandwidth map on a subcarrier-time resource through a frame synchronized at constant cycles, based on the queue status information received from each ONU.

Abstract: Systems and methods for distributing signals in an optical network are disclosed. In accordance with one embodiment of the present disclosure a method for distributing signals in an optical network comprises combining input signals into one or more output signals, determining, an availability status of optical lanes for carrying the output signals and distributing the output signals to optical transmitters associated with the optical lanes if the availability status indicates that the optical lanes are available.

Abstract: A laser system includes an array of lasers that emit light at a number of different, fixed wavelengths. A group of optical transport systems connect to the laser system. Each of the optical transport systems is configured to modulate data signals onto the light from the laser system to create optical signals and transmit the optical signals on one or more optical fibers.

Abstract: The present invention relates to a station side device having a plurality of PON lines and connected thereto. A fallback mode where a partial access control unit is not allowed to communicate communication frames is performed by switching an upper switch and a lower switch in the manner shown in the following (a) and (b): (a) output destinations of downstream frames to the first and second PON lines and inputted to the upper switch are aggregated into a first access control unit, and output destinations of the downstream frames inputted from the first access control unit to the lower switch are distributed to first and second optical transmitting and receiving units and; and (b) output destinations of upstream frames inputted from the first and second optical transmitting and receiving units and to the lower switch are aggregated into the first access control unit.

Abstract: A method and system for channelizing a Passive Optical Network (PON) Media Access Controller (MAC) includes increasing a clock rate of each of one or more PON MAC(s) to create communication lanes each comprising a plurality of N channels. The PONs are channelized according to NX, where N equals a number of ports supported by the MAC and X equals a designated operating PON MAC clocking rate allowing for leveraging of existing Passive Optical Network (PON) infrastructures to provide a more power efficient and physically smaller MAC layer for OLTs.

Abstract: An access network includes an access device having an optical interface module that outputs a plurality of pairs of optical communication signals, each of the pairs of optical communication signals comprising a modulated optical transmit signal and an unmodulated optical receive signal, each of the pairs of optical communication signals having a different wavelength. A customer premise equipment (CPE) comprises an optical interface module to receive the modulated optical transmit signal and the unmodulated optical receive signal for any of the plurality of pairs of optical communication signals. The optical interface module includes a receive module to demodulate the modulated optical transmit signal into inbound symbols and a transmit module having an optical modulator and reflective optics to modulate the unmodulated optical receive signal in accordance with a data signal and reflect a modulated optical receive signal to communicate outbound data symbols to the access device.

Abstract: A system and method for carrying control data in a preamble. A control-data bearing preamble is defined to facilitate end-to-end labeling and control-data transport. This control-data bearing preamble provides a unified labeling scheme with minimal overhead, which facilitates greater ease in parsing. The control-data bearing preamble can be converted to/from other control/labeling schemes at the edge of the control-data bearing preamble aware portion of the network.

Abstract: Certain embodiments herein relate to a hybrid cable that includes a center conductor for disturbing electrical signals and one or more optical fibers adjacent to the center conductor for distributing light signals in a service provider network. According to one configuration, materials found in a coaxial cable may be included in the hybrid cable, such as a dielectric material, one or more protective shields, and an outer protective core. Such a hybrid cable may be utilized to replace drop cables in a service provider network, which may connect an access point, such as a tap, to a customer location. Certain embodiments herein may also relate to making and installing the hybrid cable.

Abstract: A method for multi-service provisioning in an OFDMA-PON that includes linking communicatively to a core network and bandwidth provisioning, dynamically within a single wavelength, traffic from the core network to a network of multiple virtual passive optical networks VPONs for multi-service provisioning to the VPONs.

Abstract: In a method of scheduling frames, a first channel of a plurality of channels is selected for a first frame. The first frame is sent across a media-independent interface to a physical-layer device for transmission on the first channel. A data rate of the media-independent interface is greater than a data rate of the physical-layer device for the first channel. After the first frame is sent across the media-independent interface, subsequent sending of frames for the first channel across the media-independent interface is disabled for a period of time that is based at least in part on rate adaption from the data rate of the media-independent interface to the data rate of the physical-layer device for the first channel.

Abstract: The present invention relates to a method of processing a Digital Multiplex (DMX)-Visible Light Communication (VLC) address and a device using the method. In the method of processing a DMX-VLC address, a DMX-512 packet is received. It is determined whether the DMX-512 packet includes dimming data by using a start code of the DMX-512 packet. Lighting data is processed using an address recorded in a DMX-512 address field of a DMX-VLC address included in the DMX-512 packet if it is determined that the DMX-512 packet includes the dimming data. Non-lighting data is processed using an address recorded in a DMX-VLC extended address field of the DMX-VLC address if it is determined that the DMX-512 packet does not include dimming data.

Abstract: A method is performed in a communication device that includes one or more media access control (MAC) entities, a coax physical layer (PHY), and a media-independent interface coupling the one or more MAC entities with the coax PHY. In the method, a bitstream is generated that includes data frames and characters corresponding to time windows in which the coax PHY does not transmit signals. The bitstream is provided to the coax PHY through the media-independent interface. Signals corresponding to the data frames are transmitted from the coax PHY during a transmit mode. The coax PHY enters a receive mode when the bitstream contains the characters corresponding to the time windows.

Abstract: A packet transport layer passive optical network providing method controls an optical line termination device and an optical network terminal or an optical network unit of the subscriber end to transport packet transport layer passive optical network packets between the optical network terminals or the optical network units and the optical line termination device, and the optical network terminals or the optical network unit of the subscriber end becomes an end point of a packet transport layer connection.

Abstract: A digital subscriber line (DSL) unit comprises a first user port configured to communicate signals according to an Ethernet protocol and a second user port configured to communicate signals according to a second non-Ethernet protocol The DSL unit also comprises at least one DSL port configured to communicate signals according to a DSL protocol; and a processing device configured to analyze Ethernet signals received over the first user port to determine when to output data from the respective received Ethernet signals over the second user port and when to output data from the respective received Ethernet signals over the at least one DSL port. The processing device is further configured to extract data from signals received over the second user port and insert the extracted data into a corresponding Ethernet signal having a respective emulated circuit identification and to output the corresponding Ethernet signal over the first user port.

Abstract: A hybrid passive optical network (“PON”) includes a time-division multiplexing (“TDM”) optical line terminal (“OLT”) and a wavelength-division multiplexing (“WDM”) OLT. The TDM OLT communicates with a first group of customer premises (“CPs”) via TDM signals while the WDM OLT communicates with a second group of CPs via WDM signals. A remote node power splitter is coupled to receive the TDM and WDM signals and broadcast both the TDM signals and the WDM signals on all of its ports facing towards the CPs. Optical filters are disposed between the remote node power splitter and the second group of CPs. Each optical filter is configured to pass a sub-group of the WDM signals while blocking other WDM signals such that each of the second group of CPs receives its own allocation of WDM signals but does not receive WDM signals allocated to other CPs of the second group of CPs.

Abstract: An OLT includes an OLT control unit that generates a control signal for controlling a power saving operation of an ONU by specifying a different idle period with respect to a first power saving operation in which an optical receiver is operated while an optical transmitter of the ONU is controlled to a power saving state and a second power saving operation for controlling the optical transmitter and the optical receiver to the power saving state, and a station-side transmitter that transmits the control signal generated by the OLT control unit to the ONU. The ONU includes an ONU control unit that receives the control signal via the optical receiver to selectively perform the first power saving operation and the second power saving operation based on the idle period specified by the control signal.

Abstract: Disclosed herein is a Passive Optical Network (PON) system and method for detecting a fault in an Optical Network terminal (ONT). The PON system for detecting a fault in an ONT includes a plurality of ONTs for outputting optical signals in time slots allocated thereto in a time division access control manner and having at least one virtual ONT. An Optical Line Terminal (OLT) receives the optical signals output from the plurality of ONTs in the time division access control manner, and then detects a faulty ONT. According to the present invention, a faulty ONT that continuously outputs signals can be detected and action can be rapidly taken against system faults when a virtual ONT is formed in a plurality of ONTs connected to an OLT and then an optical signal in the section of the virtual ONT is detected, thus providing a reliable service.

Abstract: A method and apparatus for authentication in a passive optical network are disclosed. In the disclosure, a PLOAM message is sent from an ONU to an OLT, where the PLOAM message includes a first field for carrying an ONU identifier (ONU-ID) and a second field for carrying a first logic registration code, where the ONU-ID is assigned by the OLT to identify the ONU and wherein the first logic registration code is assigned to a user by an operation management system communicatively connected to the OLT and provisioned to the user for authentication. The OLT is configured to judge whether the first logic registration code received from the ONU matches with a second logic registration code provisioned by the operation management system to the OLT and to promote the ONU into service if the first logic registration code matches with the second logic registration code.

Abstract: An optical network unit (ONU) having a power saving function for reducing power consumption in an optical network and a power saving method thereof are provided. The ONU includes a first signal transmitter-receiver unit configured to transmit and receive a signal to and from an optical line terminal, a second signal transmitter-receiver unit configured to transmit and receive a signal to and from customer premises equipment through multiple communication ports, a signal processing unit configured to control a signal to be transmitted and received through the first signal transmitter-receiver unit and the second signal transmitter-receiver unit, and a processor configured to control powers of the first signal transmitter-receiver unit and the signal processing unit according to whether data traffic is received through the plurality of communication ports.

Abstract: An optical line terminal (OLT) configured to receive transmission requests from a plurality of both network elements (NE) and customer premises equipment (CPE), allocate a timeslot to each NE for transmission on an optical distribution network (ODN), and a timeslot to each CPE for transmission on an electrical distribution network (EDN), wherein each NE intermediates between the OLT and the CPEs. Included is a NE configured to transmit a timeslot to a CPE for transmission on an EDN allocated by an OLT, receive data frames from the CPE during the timeslot, and forward the data frames to the OLT without rescheduling. Also included is a method comprising sending a transmission request to an OLT, receiving a timeslot from the OLT for transmission on an EDN in response, transmitting data frames to a NE during the timeslot, wherein the NE forwards the data frames to the OLT without rescheduling.

Abstract: The present invention relates to an optical coupling/splitting device that realizes the splitting of a down-signal and the coupling of up-signals by the same optical device, and reduces coupling losses of the up-signal. An optical coupling/splitting device in the present invention comprises an optical coupling/splitting means for coupling a plurality of up-signals in a multi-mode for output and splitting a down-signal in a single mode for output, and a two-way optical propagation means for propagating the up-signal that is output from the optical coupling/splitting means in a multi-mode for output and propagate the down-signal in a single mode to be output to the optical coupling/splitting means.

Abstract: The invention discloses a time synchronization method and system for a passive optical network (PON) system to solve the problem that an ONU cannot be synchronized with an OLT accurately in the PON. The invention implements the time information synchronization between the ONU and the OLT by using a management path. The time information includes an information transmission delay between the ONU and the OLT and the sending time identifier information of the time information. The invention avoids the technical defect of the unfixed delay for an upper layer protocol data message in a GPON by using the characteristic that a PLOAM message or an OMCI message is not segmented during the transmission thereof in the PON, thus ensuring every ONU can be synchronized with the OLT accurately.

Abstract: A PON ring system and a method for realizing primary and backup link protection in a passive optical network (PON) are provided. A PON ring is established between at least two optical line terminations (OLTs) through at least two user side edge nodes or network side edge nodes. Each of the OLTs is coupled to any other OLT through the at least two edge nodes. Two links respectively in a clockwise direction and a counterclockwise direction exist in the PON ring, in which one link is a primary link and the other is a backup link. Node of the links adopt the transmission mode of “multiple sending and selective receiving”. Therefore, the present invention reduces the impact on the PON caused by single link failure in the network.

Abstract: The inventive concept relates to an optical line terminal registering optical network terminals having overlapping serial numbers. The optical line terminal may include a memory storing serial number information of optical network terminals of which a registration is completed in a storage region; and a control part that if a serial number by a serial number request is received from optical network terminals, the received serial number is compared with the serial number information of the memory and if they overlap each other, a previously set preliminary identifier is allocated to the optical network terminal having an overlapping serial number.

Abstract: A method of transmitting data in an optical transport network is provided. The method comprises generating an optical transmission unit frame including an in-band area including a first area to which information data is allocated and a second area to which the information data is not allocated and an out-band area including parity information and transmitting the data through the optical transmission unit frame.

Abstract: The present invention discloses a method for acquiring a PON port association relationship. An OLT where a standby PON port is located receives a protection packet from an optical network unit, parses the protection packet to obtain an identifier of an active PON port carried in the packet, and acquires an association relationship between the active PON port and the standby PON port according to an identifier of the standby PON port receiving the protection packet. When the present invention is implemented, the OLT where the standby PON port is located can acquire an association relationship between an active PON port and a standby PON port, and determine, according to the association relationship, whether the protection packet is valid or acquire, according to the association relationship, configuration information of the active PON port.

Abstract: An optical transmission device, which transmits a first frame containing second frames, includes newly adding and allocating, when a bit rate of a specific second frame among the second frames is to be changed, a time slot corresponding to an increase in the bit rate of the specific second frame to time slots previously set for the second frames in time slots of the first frame; and inputting a dummy signal as data to the newly-added time slot while performing such a setting that both of: a data writing speed and a data reading speed; and a delay time between writing and reading of the data for the newly-added time slot are in agreement with both of: a data writing speed and a data reading speed; and a delay time between writing and reading of the data for each time slot of the previously-set time slots.

Abstract: An apparatus for enabling a passive optical network (PON) having an OLT and at least one ONU on supporting time synchronization is disclosed. The apparatus comprises a timestamp correction module configured to make at least one network delay between the OLT and the at least one ONU of the PON equivalent to an equivalent path delay, wherein the timestamp correction module, through the PON, makes the at least one ONU responsible for modifying the timestamp in at least one PTP packet from the OLT, so that a slave clock at the backend of the at least one ONU is equivalent to synchronizing with a virtual master clock. The disclosure computes and corrects PTP commands so that the PTP clock at an ONU's backend may synchronize precisely with the master clock at an OLT's front end.

Abstract: An optical fiber transmission distribution assembly, wherein the assembly comprises at least a first splitter having a first split ratio of 1:x (where x is an integer) connected to optical drop cables leading to subscribers, and at least a second splitter having a second split ratio of 1:y (where y is an integer and is different from x), and transfer means whereby an optical drop cable connected to the first splitter can be transferred to receive split optical signals from the second splitter, thereby enabling the signal in the transferred drop cable to be further split by addition of a third splitter at a ratio of 1:p (where p is an integer), to provide p subscriber connection points each having a 1:p*y split ratio at the subscriber end of the transferred drop cable.

Abstract: A joint switching method for an aggregation node, an aggregation node, and an optical network protection system including an aggregation node are provided. By monitoring information transferred between an active optical line terminal (OLT) and a broadband network gateway (BNG), the aggregation node finds a fault in time according to the monitored information and when a fault occurs, the aggregation node starts a local protection solution, enables a corresponding backup port connected to a backup OLT corresponding to the active OLT, and disables an active port connected to the active OLT. Through the method, when the active OLT is switched to the backup OLT, the aggregation node performs joint switching, which ensures normal communication.

Abstract: A burst transmission method and a receiver resetting method and apparatus in a Passive Optical Network (PON) are provided. A burst receiver resetting method in a PON includes: receiving a preamble sequence and synchronizing data; after synchronizing the data, continuing to receive the data, and matching a Burst Terminator (BT); and resetting a receiver after successfully matching the BT. Meanwhile, an apparatus for implementing the method and a corresponding burst data transmission method are provided. By using the burst receiver resetting method and apparatus in the PON and the corresponding burst transmission method at an Optical Network Unit (ONU) burst transmission end, a Reach Extender (RE) does not need to unpack upstream burst bandwidth allocation information carried in downstream data.

Abstract: In general, a system and method provides secure communications between optical transceivers in an optical communication system. Two or more optical transceivers may be provisioned with one or more passcodes assigned to the transceivers, which may be used to indicate that received data traffic is intended for the transceivers. The transceivers may be configured to format data traffic with a secure version of the passcode in the overhead of the outbound signal and may be configured to determine if an inbound signal includes a secure version of the passcode provisioned in that transceiver. A transceiver may prevent data traffic from being read when the transceiver is not provisioned to receive data traffic with the embedded secure passcode and may insert an alternative maintenance signal (AMS) into an outbound signal in an opposite direction, at least temporarily, until the inbound signal includes the appropriate passcode.

Abstract: A GPON module comprises a housing and a circuit board disposed in the housing. The circuit board further includes ground lines that substantially isolate regions of the circuit board, an electro-optical interface for converting an inbound optical signal to an electrical signal and processing circuitry that is arranged to provide an electrical RF signal to an RF interface. The RF interface comprises a three-pin RF connector exposed from the housing, wherein the RF connector is coupled directly to the circuit board, and two of the three pins are coupled to ground.

Abstract: A fiber optic network having a multi-level architecture is disclosed. A first level of the fiber optic network comprises a first branch. The first branch comprises a plurality of first branch optical fibers optically coupled to a distribution cable and a first branch fiber optic network device. The first branch fiber optic network device is configured to optically couple a first predetermined one of the plurality of first branch optical fibers to a respective first predetermined sub-branch optical fiber, and a second predetermined one of the plurality of first branch optical fibers to a second predetermined sub-branch optical fiber. A second level of the fiber optic network comprises a sub-branch. The sub-branch comprises a first sub-branch fiber optic network device and a second sub-branch fiber optic network device.

Abstract: The present invention provide a method for forwarding a multicast program includes: receiving a multicast join request message requesting an on-demand program from a user; obtaining forwarding decision information according to the multicast join request message; determining a decision result corresponding to the forwarding decision information according to the forwarding decision information and forwarding relation data, where the decision result is forwarding according to PON replication or forwarding according to user replication, the forwarding relation data includes data elements indicating correspondence between various types of forwarding decision information and various types of forwarding modes, and the various types of forwarding modes include the forwarding according to PON replication and the forwarding according to user replication; and forwarding the on-demand program to the user according to the decision result.

Abstract: A power saving method in a passive optical network, including: when receiving an upstream burst timeslot allocated by the Optical Line Terminal (OLT) after a power supply of the Optical Network Unit (ONU) is turned off, the ONU dividing the upstream burst timeslot into one or more upstream burst timeslots; and the ONU turning on own laser in the upstream burst timeslot belonging to the ONU, and after sending one or more emergent Physical Layer Operations, Administration and Maintenance (PLOAM) messages to OLT in each upstream burst timeslot, promptly turning off the own laser. A power saving system in a passive optical network and an optical network unit is provided. The invention can decrease the power supply volume of an electric supply installation in a power-off ONU and reduce the cost of the electric supply installation.

Abstract: A method of allocating bandwidth in a network comprising receiving a GATE message allocating a transmission time window in an optical portion of the network to a coaxial network unit (CNU) in a coax portion of the network, and generating a coax network resource map by mapping the transmission time window to communication channel resources in the coax portion of the network; and sending the coax network resource map to the CNU.

Abstract: An optical data link includes first and second pluralities of transmission devices, at least one of which is configured as an array. A multichannel transmission link has a first end connected to the first plurality of transmission devices and a second end connected to the second plurality of transmission devices so as to form a plurality of parallel transmission channels therebetween. The multichannel transmission link includes a multicore fiber with a plurality of individual cores having a configuration matching the array configuration of the at least one plurality of transmission devices. The multicore fiber has an endface connected directly to the at least one plurality of transmission devices, with the individual cores of the multicore fiber aligned with respective devices in the at least one plurality of transmission devices. Further described are access networks and core networks incorporating a transmission link comprising at least one span of a multicore fiber.

Abstract: The present invention discloses a method and system for accurate time transfer in PON. An Optical Line Terminal (OLT) ranges Optical Network Units (ONUs) and obtains ranging information, then, triggered by the periodic Pulse per n Second (PPnS), generates a PPnS timestamp based on the local reference counter and the Time of Day (TOD) above second; OLT transmits the ranging information, the periodic PPnS timestamp and TOD to ONUs; ONUs predicts the time of the next second according to said periodic PPnS timestamp, TOD and ranging information, and outputs the corresponding PPnS. The invention is characterized by the combination of the features of PON point to multi-point and PON ranging into its time transfer method, the high accuracy of time transfer, and the low hardware costs for OLT and ONU, as well as the extremely small bandwidth occupancy.

Abstract: A radio-over-fiber (RoF) hybrid wired/wireless transponder is disclosed that is configured to provide both wireless and wired communication between a hybrid head-end and one or more client devices. The hybrid transponder includes optical-to-electrical (O/E) and electrical-to-optical (E/O) conversion capability and is configured to frequency multiplex/demultiplex electrical “wired” signals and electrical “wireless” signals. The electrical wireless signals are wirelessly communicated to the client device(s) via a multiple-input/multiple-output (MIMO) antenna system within a cellular coverage area. The electrical wired signals are communicated to the client device(s) via a wireline cable that plugs into a wireline cable port on the transponder. The hybrid RoF system includes a hybrid head-end capable of transmitting and receiving wired and wireless optical signals, and an optical fiber cable that is optically coupled to the hybrid head-end and to at least one hybrid transponder.

Abstract: Terminals of upstream and downstream sides of an in-service line and a detour line are connected by optical couplers. An optical oscilloscope is connected to one optical coupler, and a chirped pulse light source is connected to the other optical coupler to thereby form dualized lines. The detour line includes an optical line length adjuster for compensating for the phase difference of optical transmission signals that occurs because of the optical line length difference with the in-service line. Pulse light in which an optical frequency is chirped is transmitted from the chirped pulse light source. The pulse light is branched by the second optical coupler, passes through the in-service line and the detour line, is multiplexed again by the first optical coupler, and is measured by the optical oscilloscope.