Bidirectional Patents (Class 398/72)
  • Patent number: 8000602
    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.
    Type: Grant
    Filed: April 17, 2008
    Date of Patent: August 16, 2011
    Assignee: PMC-Sierra Israel Ltd.
    Inventors: Onn Haran, Lior Khermosh, Victor Vaisleib
  • Patent number: 7995914
    Abstract: An approach is provided for performing fault recovery using composite transport groups (CTGs). A first logical channel is established within a composite transport group, wherein the first logical channel is established over a first link associated with a first service provider to a customer premise equipment (CPE) node configured to transport packets. A second logical channel is established within the composite transport group, wherein the second logical channel is established over a second link associated with a second service provider to an optical node. Packets are received over the first logical channel. Packets are received over the second logical channel if the first logical channel experiences a fault condition, wherein switching to the second logical channel is transparent to the CPE node.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: August 9, 2011
    Assignee: MCI Communications Services, Inc.
    Inventor: Ning So
  • Patent number: 7995920
    Abstract: Optical network terminal (ONT) power failure management. A system for permitting a customer of a telecommunication company, for whom fiber to the premises (FTTP) has been installed, to control operating features associated with operation of a battery backup unit (BBU) which is used, during power failure, for powering the ONT associated with the FTTP installation and the customer's telephone(s). The controlling of these features includes utilization of signal-controlled switches, which are manually over-rideable by the customer, thereby providing the desired operating feature control.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: August 9, 2011
    Assignee: Verizon Patent and Licensing Inc.
    Inventor: Stanley J. Wynman
  • Patent number: 7986880
    Abstract: A return path system includes inserting RF packets between regular upstream data packets, where the data packets are generated by communication devices such as a computer or internet telephone. The RF packets can be derived from analog RF signals that are produced by legacy video service terminals. In this way, the present invention can provide an RF return path for legacy terminals that shares a return path for regular data packets in an optical network architecture.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: July 26, 2011
    Assignee: Enablence USA FTTx Networks Inc.
    Inventors: James O. Farmer, Deven J. Anthony, Stephen A. Thomas, Patrick W. Quinn
  • Patent number: 7978976
    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.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: July 12, 2011
    Assignee: Schofield Technologies LLC
    Inventors: Olli-Pekka Pohjola, Ari Tervonen, Harri T. Jarvinen, Markku Oksanen
  • Patent number: 7978977
    Abstract: The present invention is directed towards monitoring and adjusting a power level of reverse subcarrier signals at an input of an optical node as opposed to at an input of a CMTS blade. Advantageously, reverse subcarrier signals are digitally transmitted throughout the optical link thereby avoiding the use of attenuators in the optical link. Therefore, any attenuation of the power level of the reverse subcarrier signals is caused by an RF feeder portion of the communications system. The CMTS blade then detects the power level of the reverse subcarrier signal that is equivalent to the power level at the input of an optical node and sends a control signal to CPE adjusting the transmitter power level without affecting the optical node dynamic range.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: July 12, 2011
    Inventor: Lamar E. West, Jr.
  • Patent number: 7974532
    Abstract: A system and method for management of bandwidth in a fiber optic, ethernet-based, TDMA communications system. A request/grant process is used to control the use of upstream bandwidth. A sense of time must therefore be shared by a headend and remote end-user devices. The invention provides for a gigabit media-independent interface in a media access controller to detect start-of-frame delimiters in incoming data. This allows for synchronization of a headend and end-user devices. The invention also allows for phase locking a transmit bit rate, at a headend, to the headend's clock. Transmitted data can the be used downstream to derive a local clock. Synchronization can also be maintained by the use of synchronization bytes in MPEG frames and/or variable length frames. Efficient bandwidth usage can also be facilitated by the use of maximum data units in allocating bandwidth in unsolicited grants, and by allowing flexible fragmentation and/or prioritization of internet protocol (IP) packets.
    Type: Grant
    Filed: March 19, 2009
    Date of Patent: July 5, 2011
    Assignee: Broadcom Corporation
    Inventors: Dolors Sala, Ajay Chandra V. Gummalla, Niki R. Pantelias
  • Patent number: 7974533
    Abstract: An optical network is provided including a first optical network section operatively coupled to a carrier facility configured to transmit traffic onto channels in the first optical network section. A second optical network section may be operatively coupled to the first optical network section at a first node. Additionally, the second optical network section may be operatively coupled to a customer location at a second node. The first and second nodes may include tunable filters for passing traffic via at least one channel from the first optical network section to the second optical network section.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: July 5, 2011
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: Glenn A. Wellbrock, Tiejun J. Xia
  • Patent number: 7965939
    Abstract: A system for providing bi-directional RF services over relating to a point-to-multipoint Passive Optical Network (PON).
    Type: Grant
    Filed: June 15, 2007
    Date of Patent: June 21, 2011
    Assignee: Northpeak Enterprises, Inc.
    Inventors: Ketan Gadkari, Tom Warner
  • Patent number: 7962047
    Abstract: When an optical signal that is a wide dynamic range and different in level depending on burst signals is input as in a GPON system, a preamplifier can stably control the gain within a short preamble. The gain changeover of the preamplifier is controlled by the aid of timing information that is extracted from a data signal as data count number, to change over the gain at a high speed and with high precision. A level detector, a preamble recovery, a counter, and a control circuit are disposed within the preamplifier in addition to a TIA main body. In order to suppress the band deterioration or the phase margin reduction which are attributable to the gain changeover, there is provided a bias terminal for conducting a current injection and a current drawing with respect to the signal amplification transistor of the TIA main body.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: June 14, 2011
    Assignee: Hitachi, Ltd.
    Inventor: Tomoo Murata
  • Patent number: 7962037
    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.
    Type: Grant
    Filed: November 19, 2009
    Date of Patent: June 14, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Masahiko Mizutani, Takeshi Shibata, Tohru Kazawa, Yoshihiro Ashi, Masanobu Kobayashi, Masayuki Takase
  • Publication number: 20110135307
    Abstract: Fiber optic terminals, systems, and methods for providing differentiated network services to subscribers of a fiber optic network are disclosed. In certain embodiments, fiber optic terminals and methods are disclosed for providing more than one network service to subscribers supported by the same fiber optic terminal. In one embodiment, a fiber optic terminal is provided comprising a first optical path connected to a first network-side optical fiber providing a first network service to a first subscriber-side optical fiber. The fiber optic terminal also comprises a second optical path connected to a second network-side optical fiber providing a second network service differentiated from the first network service to a second subscriber-side optical fiber. In this manner, differentiated network services can be provided to subscribers supported by the fiber optic terminal by configuring connections of the subscribers to either the first optical path or second optical path in the fiber optic terminal.
    Type: Application
    Filed: December 4, 2009
    Publication date: June 9, 2011
    Inventors: Mark E. Conner, Kenneth F. Dunn, JR.
  • Patent number: 7957647
    Abstract: In a WDM-PON system wherein a plurality of ONUs transfer signals by sharing wavelengths, one wavelength dedicated to a ranging procedure is set, and the ranging is performed with only the dedicated wavelength, so as to measure reciprocating delay times. At the other wavelengths, transmission signals from a plurality of ONUs are transferred in time division multiplexing based on the obtained reciprocating delay times. An OLT includes a burst receiver circuit for only the wavelength dedicated to the ranging, and subsequently to the ranging, the OLT adjusts transmission amplitudes and transmission phases for the ONUs, so as to equalize received amplitudes and received phases in the OLT. For this purpose, the OLT includes means for measuring the amplitudes and phases of received signals, as the burst receiver circuit, and it includes a table for managing the received amplitudes and received phases of the respective ONUs.
    Type: Grant
    Filed: April 15, 2008
    Date of Patent: June 7, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Kazawa, Yusuke Yajima, Masaki Oohira
  • Patent number: 7953325
    Abstract: An optical fiber network can include an outdoor laser transceiver node that can be positioned in close proximity to the subscribers of an optical fiber network. The outdoor laser transceiver node does not require active cooling and heating devices that control the temperature surrounding the laser transceiver node. The laser transceiver node can adjust a subscriber's bandwidth on a subscription basis or on an as-needed basis. The laser transceiver node can also offer data bandwidth to the subscriber in preassigned increments. Additionally, the laser transceiver node lends itself to efficient upgrading that can be performed entirely on the network side. The laser transceiver node can also provide high speed symmetrical data transmission. Further, the laser transceiver node can utilize off-the-shelf hardware to generate optical signals such as Fabry-Perot (F-P) laser transmitters, distributed feed back lasers (DFB), or vertical cavity surface emitting lasers (VCSELs).
    Type: Grant
    Filed: August 26, 2009
    Date of Patent: May 31, 2011
    Assignee: Enablence USA FTTX Networks, Inc.
    Inventors: James O. Farmer, John J. Kenny, Patrick W. Quinn, Thomas A. Tighe, Paul F. Whittlesey, Emmanuel A. Vella
  • Patent number: 7949256
    Abstract: A method is provided for increasing downstream bandwidth in an optical network that includes providing a downstream terminal comprising a digital output path and an analog output path. The method also includes receiving a signal comprising at least one wavelength at the downstream terminal. The method further includes selectively processing the signal at the downstream terminal. The signal is selectively processed at the downstream terminal by processing the signal on the analog output path if the signal comprises analog video data and processing the signal on the digital output path if the signal comprises data to be converted to a digital bit stream.
    Type: Grant
    Filed: January 5, 2007
    Date of Patent: May 24, 2011
    Assignee: Fujitsu Limited
    Inventors: Martin Bouda, Takao Naito
  • Patent number: 7945164
    Abstract: A method, an apparatus, and a system where multiple lower bandwidth optic Ethernet (e.g. 1000Base-FX) signals can be interleaved or encoded onto a single fiber optic link by overclocking the physical layer elements in such a manner as to be transparent to the data link layer and other higher network layers in the Open Systems Interconnection Reference Model (OSI Model) are provided. Such embodiments may provide increased port density over the existing fiber optic gigabit Ethernet (GbE) standards. In embodiments where multiple GbE signals are not channelized, overclocking the physical layer elements may provide increased bandwidth for a single link over existing fiber optic GbE standards.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: May 17, 2011
    Assignee: Cisco Technology, Inc.
    Inventor: James T. Theodoras, II
  • Patent number: 7945166
    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.
    Type: Grant
    Filed: December 7, 2007
    Date of Patent: May 17, 2011
    Assignee: HOYA Corporation USA
    Inventor: Henry A. Blauvelt
  • Patent number: 7945163
    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.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: May 17, 2011
    Assignee: NEC Corporation
    Inventor: Hirokazu Ozaki
  • Patent number: 7941055
    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.
    Type: Grant
    Filed: November 9, 2006
    Date of Patent: May 10, 2011
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Wei Huang, Jun Zhao, Peilong Tan, Tao Jiang, Feng Wang, Jun Chen, Yuntao Wang, Huafeng Lin, Guo Wei
  • Patent number: 7936991
    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.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: May 3, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Toshiki Sugawara, Masahiko Mizutani, Hiroki Ikeda, Kenichi Sakamoto
  • Patent number: 7929862
    Abstract: After implementing a scrambler upon an electric signal of digital signals to be transmitted to a user terminal, this electric signal is converted into a digital optical signal, and an analog optical signal and this digital optical signal are multiplexed by wavelength division multiplexing, thereby reducing influence of cross-talk interference that is exerted on the analog optical signal by the digital optical signal.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: April 19, 2011
    Assignee: Fujitsu Limited
    Inventors: Katsuhiko Hakomori, Hiroshi Nishimoto, Akihiko Ichikawa
  • Patent number: 7925156
    Abstract: Apparatus and method to measure the quality of burst signals and to perform optical line diagnostics in and optical passive optical network (PON). Statistical information about phase noise (jitter), signal distortion, clock distortions, and any other effects present in burst signals is generated. The statistics are based on phase and bit-length distortions, direction and length of the effect as detected by a phase error detector integrated in a burst mode clock and data recovery (BCDR) circuit. The invention can be further adapted to perform optical line diagnostics to detect the root cause performance degradation and failures in the PON, thereby providing an optical layer supervision tool for monitoring the PON. The statistical information can be used to estimate the quality of service (QoS) per customer connected to the PON. In addition, the generated statistic information can be used to calibrate transmission parameters of optical network unit (ONU) transmitters.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: April 12, 2011
    Assignee: Broadlight, Ltd.
    Inventors: Raviv Weber, Amiad Dvir, Eli Elmoalem, Alex Goldstein, Igor Elkanovich, David Avishai
  • Patent number: 7925164
    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.
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: April 12, 2011
    Assignee: Broadlight Ltd.
    Inventors: Gal Sitton, Jacob Harel, Ifat Naaman
  • Patent number: 7920792
    Abstract: In accordance with the teachings of the present invention, a system and method for managing communication in a hybrid passive optical network (HPON) is provided. In a particular embodiment, the method includes transmitting, at a first wavelength, a first configuration message on the HPON. The method also includes receiving at one or more of a plurality of receivers at an optical line terminal (OLT) one or more configuration response messages from one or more optical network units (ONUs) in a first set of ONUs. The method further includes, based on the configuration response messages from the first set of ONUs, associating, in a database, each ONU in the first set of ONUs with the first wavelength and with the receiver receiving the configuration response message from the ONU. The method also includes, after transmitting the first configuration message, transmitting, at a second wavelength, a second configuration message on the HPON.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: April 5, 2011
    Assignee: Fujitsu Limited
    Inventors: Paparao Palacharla, Martin Bouda, Takao Naito
  • Patent number: 7920789
    Abstract: A system for communication of signals between remote devices and monitoring and control devices via fiber. The system in accordance with one aspect of the invention includes a plurality of remote interface units each coupled to a corresponding one of the remote devices, a base unit coupled to one or more monitoring devices and one or more control devices, and a central hub coupled between the base unit and the plurality of remote interface units. The central hub is coupled to the base unit by a first fiber optic link, and is coupled to the remote interface units by additional fiber optic links.
    Type: Grant
    Filed: January 5, 2009
    Date of Patent: April 5, 2011
    Assignee: Multidyne Electronics Inc.
    Inventors: Vincent Jachetta, Brian C. Moore, James G. Jachetta, Francis P. Jachetta
  • Patent number: 7917032
    Abstract: The present invention relates to a multi-bit-rate optical communication method, optical network units, and an optical line terminal that enable multi-bit-rate transmission of low bit-rate data and high bit-rate data while maintaining compatibility with existing systems and reducing upgrade costs of optical network units and labor required for the upgrade, wherein the optical line terminal transmits a first data area including frame synchronization information in a predetermined frame format at a first bit rate and a second data area at a second bit rate which is the first bit rate×Mdown (Mdown>1), and any of the optical network units performs reception processing at a rate once every Mdown-bit to detect the frame synchronization information in the first data area and, based on detection timing thereof, performs reception processing of the second data area by a bit.
    Type: Grant
    Filed: October 18, 2006
    Date of Patent: March 29, 2011
    Assignee: Fujitsu Limited
    Inventor: Kazuyuki Mori
  • Patent number: 7912372
    Abstract: The present invention relates to a passive optical network, which inexpensively improves the spectral efficiency of an access network and is capable of increasing the number of subscribers per channel by using WDM in combination with Time Division Multiplexing (TDM) or SubCarrier Multiple Access (SCMA) to expand a conventional WDM passive optical network.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: March 22, 2011
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang Hee Lee, Jin Serk Baik, Keun Youl Park, Seung Hyun Jang, Ki Man Choi, Hyun Sik Min
  • Patent number: 7904550
    Abstract: An apparatus including a section acquiring the information as to the information processor of the delivery destination in the second network, a section alternatively providing service to an access from the first network by using the acquired information, a section receiving and delivering the information from the first network by using the alternatively supplied service, a section changing the information processor of the delivery destination in the second network to the service providing state, when the apparatus receives the information including the contents from the first network and the information processor of the delivery destination in the second network is not in the service providing state, it is possible to change the information processor of the delivery destination to the service providing state and deliver information including the contents to the information processor of the delivery destination.
    Type: Grant
    Filed: February 25, 2008
    Date of Patent: March 8, 2011
    Assignee: Fujitsu Limited
    Inventors: Takuya Sakamoto, Toru Kamiwada
  • Publication number: 20110038632
    Abstract: A PON extender includes an optical amplifier that is adapted to compensate optical power for PON signals in a downlink channel. An optical control switch is connected with an ONU and is adapted to extract overhead information of the PON signals in the downlink channel and to select one channel of ONU uplink signals as output uplink channel PON signals according to the extracted overhead information. A regenerating device is adapted to regenerate optical signals for the uplink channel PON signals output under control of the optical control switch.
    Type: Application
    Filed: October 22, 2010
    Publication date: February 17, 2011
    Applicant: HUAWEI TECHNOLOGIES CO., LTD.
    Inventor: Shimin Zou
  • Patent number: 7889990
    Abstract: In a GPON system conforming to ITU-T Recommendations G.984.3, an optical line terminal is provided which has an active bandwidth allocation function that preferentially puts small bandwidth signals in a particular segment of a frame, e.g., at a head of the frame, to prevent fragmentations that may occur particularly when allocating small bandwidths of about 100 kbits/s.
    Type: Grant
    Filed: July 27, 2007
    Date of Patent: February 15, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Kazawa, Kenichi Sakamoto, Ryosuke Nishino
  • Patent number: 7885542
    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.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: February 8, 2011
    Inventor: Robert R. Riggsby
  • Patent number: 7885543
    Abstract: A device determines a bandwidth demand for traffic provided between a line terminal (LT) and multiple optical network terminals (ONTs), and dynamically tunes, based on the determined bandwidth demand, one or more tunable filters provided in the LT and the multiple ONTs to one of balance the traffic, protect the traffic, or increase available bandwidth for the traffic.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: February 8, 2011
    Assignee: Verizon Patent and Licensing Inc.
    Inventors: David Z. Chen, Joseph M. Finn, Steven Gringeri
  • Patent number: 7881607
    Abstract: A method and corresponding apparatus is disclosed for determining a particular Optical Network Terminal (ONT) in a Passive Optical Network (PON) is malfunctioning by sending a continuous stream of light up a shared fiber, which results in adversely affecting communications between the ONT and an Optical Line Terminal (OLT). The example embodiment verifies the failure is due to a faulty optical transmitter in the ONT and not a different network fault, such as a fiber optic line cut or power outage. Through the use of the example embodiment, a service provider can determine in an automated manner which specific ONT of a PON is malfunctioning.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: February 1, 2011
    Assignee: Tellabs Petaluma, Inc.
    Inventors: David A. DeLew, Ryan D. Houlgate, Nathan D. Knuth, Manic C. Steyn, Weijun Li
  • Patent number: 7877013
    Abstract: A wavelength division multiplexing based passive optical network is disclosed. The network includes an optical line terminal; a power optical splitter connecting to the optical line terminal by an optical fiber; and several optical network units. Each of the optical network units connects to the power optical splitter by each of other optical fibers by a random process.
    Type: Grant
    Filed: February 26, 2007
    Date of Patent: January 25, 2011
    Assignee: Futurewei Technologies, Inc.
    Inventor: Frank J. Effenberger
  • Patent number: 7877014
    Abstract: A return path system includes inserting RF packets between regular upstream data packets, where the data packets are generated by communication devices such as a computer or internet telephone. The RF packets can be derived from analog RF signals that are produced by legacy video service terminals. At a data service hub, a digitized-RF-to-packet converter (DRPC) can convert the RF packets into standard sized packets such as Ethernet packets for processing by a video services controller. In this way, the present invention can provide an RF return path for legacy terminals that shares a return path for regular data packets in an optical network architecture.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: January 25, 2011
    Assignee: Enablence Technologies Inc.
    Inventors: James O. Farmer, Stephen A. Thomas, Patrick W. Quinn, Deven J. Anthony
  • Patent number: 7873277
    Abstract: In a PON system with WDM, at the time of initial setting, each ONU negotiates with an OLT, and automatically acquires a wavelength which can be used by the ONU. One wavelength for negotiation of assigned wavelength is fixed as a default, and a newly connected ONU first uses the wavelength. The OLT 200 includes a plurality of light sources for downstream communication. The ONU 300 includes a wavelength variable filter selectively receiving one of wavelengths of downstream communication, and a wavelength variable light source selectively emitting light of one of plural wavelengths for upstream communication. The ONU 300 uses a transmission wavelength (for example, ?u32) for negotiation and transmits a wavelength assignment request 1000 to the OLT 200. The OLT 200 selects a wavelength ?u1 to be assigned from unused wavelengths, and transmits wavelength information to the ONU 300. The OLT 200 and the ONU 300 communicates using the notified wavelengths.
    Type: Grant
    Filed: June 27, 2007
    Date of Patent: January 18, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Kazawa, Kenichi Sakamoto, Ryosuke Nishino
  • Patent number: 7865081
    Abstract: Disclosed is an architecture enabling premium services to be provided over fiber to high-end users/customers. This architecture has a plurality of nodes and a passive optical device inserted prior to one of the nodes. The optical device allows wavelengths provisioned for original service(s) to pass through with minimal loss, while other wavelengths provisioned for the premium services are diverted onto a new fiber. This new fiber may be installed at the time of the upgrade, but, sometimes, dark fiber is available. Dark fiber is fiber that carries no optical signals.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: January 4, 2011
    Assignee: AT&T Intellectual Property II, L.P.
    Inventor: Sheryl Leigh Woodward
  • Patent number: 7860391
    Abstract: A WDM communication system that includes links traversing substantially inaccessible regions may tolerate multiple failures. In one implementation, a primary link spanning such a region is protected by a backup link. To provide further fault tolerance diverse paths may be provided to and from this backup link. The region may be, for example, an ocean.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: December 28, 2010
    Assignee: Cisco Technology, Inc.
    Inventors: Aldo Aprile, Massimo Cambiaghi, Valerio Viscardi
  • Patent number: 7848654
    Abstract: A radio-over-fiber (RoF) wireless picocellular system adapted to form an array of substantially non-overlapping individual picocells by operating adjacent picocells at different frequencies is operated to form one or more combined picocells. The combined picocells are formed from two or more neighboring picocells by the central head-end station operating neighboring picocells at a common frequency. Communication between the central head-end station and a client device residing within a combined picocell is enhanced by the availability of two or more transponder antenna systems. Thus, enhanced communication techniques such as antenna diversity, phased-array antenna networks and multiple-input/multiple-output (MIMO) methods can be implemented to provide the system with enhanced performance capability. These techniques are preferably implemented at the central head-end station to avoid having to make substantial changes to the wireless picocellular system infrastructure.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: December 7, 2010
    Assignee: Corning Cable Systems LLC
    Inventors: Michael Sauer, Richard S. Vodhanel, Martyn N. Easton, Aravind Chamarti, Jack Winters
  • Patent number: 7848653
    Abstract: Embodiments of the present invention provide a method for transmitting low rate signals over an optical transport network, including: adapting the low rate signals into low rate optical channel data units of the same rate level with the low rate signals; asynchronously mapping each of the low rate optical channel data units into a low rate optical channel data tributary unit respectively, and generating justification overhead used for rate adaptation for each of the low rate optical channel data units; and forming a higher order optical channel data unit with at least one low rate optical channel data tributary unit and justification overhead corresponding to the low rate optical channel data tributary unit. The present invention enables the optical transport network to support mapping, multiplexing and highly efficient transmission of low rate signals.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: December 7, 2010
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: Shimin Zou
  • Patent number: 7848643
    Abstract: A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON) includes a central office and remote nodes. When there is a fault in an optical fiber connecting a first blue/red band coupler to a blue/red band coupler R11, optical signals are inputted/outputted thereto/therefrom through a first 1×2 optical switch and a second blue/red band coupler, and when there is a fault in an optical fiber connecting the second blue/red band coupler to a blue/red band coupler R21, optical signals are inputted/outputted thereto/therefrom through the second 1×2 optical switch and the first blue/red band coupler.
    Type: Grant
    Filed: July 6, 2009
    Date of Patent: December 7, 2010
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yun Chur Chung, Eui Seung Son, Kyung Woo Lim, Kwan Hee Han
  • Patent number: 7848652
    Abstract: A wavelength division multiplexing passive optical network system is provided. A central office generates a multi-mode light having a mode interval equal to a period interval of a multiplexing filter of the remote node and the multi-mode light is used to control a wavelength of an uplink transmission optical signal of the optical network unit. A remote node multiplexes the multi-mode light with the multiplexing filter to transmit the multiplexed multi-mode light to the optical network unit and demultiplexes the uplink transmission optical signal to transmit the demultiplexed uplink transmission optical signal to the central office. An the optical network unit generates the uplink transmission optical signal by modulating a data signal with a Fabry-Perot laser which uses the multiplexed multi-mode light as an injection optical source. Accordingly, it is possible to control a wavelength of a transmitter of the optical network unit by using the injection optical source generated by the central office.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: December 7, 2010
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Moon Seob Lee, Byung Tak Lee, Hyun Seo Kang, Jai Sang Koh
  • Publication number: 20100296811
    Abstract: There are provided multiple candidates for FEC codes selectable for each of the ONTs. An OLT is provided with: means for storing redundancy and a code length of each FEC code in a table; means for selecting an FEC code; means for encoding or decoding data using the selected FEC code; means for calculating a bandwidth in consideration for the FEC redundancy and the code length with reference to the table during band assignment calculation; and means for notifying the destination ONT of the selected FEC code.
    Type: Application
    Filed: May 24, 2010
    Publication date: November 25, 2010
    Applicant: HITACHI, LTD.
    Inventors: Masaki Ohira, Tohru Kazawa, Yusuke Yajima, Akihiko Tsuchiya
  • Patent number: 7840135
    Abstract: A method for detecting a failure network terminal in a Passive Optical Network includes: changing timeslots assigned to potential failure network terminals one by one; and determining the failure network terminal according to uplink data frames sent by the potential failure network terminals whose timeslots are changed. Embodiments of the present invention also disclose an apparatus and system for detecting a failure network terminal. The solution of the present invention may detect which Optical Network Unit/Terminal (ONU/ONT) fails and perform the corresponding processing in accordance with embodiments of the present invention, which recovers the system health and improves the network security, stability and self-healing ability.
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: November 23, 2010
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Jun Zhao, Wei Huang, Yuntao Wang, Huafeng Lin, Guo Wei
  • Patent number: 7840137
    Abstract: A station-side apparatus adapted for use in a passive optical network (PON) system is disclosed, which remotely collects inside information of optical network terminals (ONTs) even before completion of start-up of an optical network unit (ONU), permits an obstruction-detected ONU to send out an emergency notification message to the station-side apparatus, e.g., optical line terminal (OLP), and permits the OLT that received this message to interrupt the transmission of an upload signal toward another ONU after the elapse of a fixed length of time while at the same time receiving information from the obstruction-suffering ONU to thereby facilitate cut-and-divide or “segmentation” of obstruction. A subscriber-side device for use in the PON system is also disclosed.
    Type: Grant
    Filed: July 27, 2007
    Date of Patent: November 23, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Tohru Kazawa, Kenichi Sakamoto, Ryosuke Nishino
  • Patent number: 7831145
    Abstract: The present disclosure provides a passive optical network (PON) system and a method for protecting the service of the system for service recovery and fault locating in case of a failure of the network, wherein the PON system comprises an optical line terminal (OLT), an optical distribution network (ODN) and an optical network terminal (ONT) equipment protection group comprising a plurality of ONT equipment groups, each of which is connected to at least one of other ONT equipment groups within the ONT equipment protection group for the mutual protection relationship. The PON system of the present disclosure does not require equipment and link redundancy for backup, contributes to reduced cost and improved utilization of resources, and provides a means for diagnosing any faults of the links and equipment in the network.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: November 9, 2010
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Hai Gao, Gang Zheng
  • Patent number: 7831147
    Abstract: This invention provides a new architecture for a communication system between head-ends and end-users which expands bandwidth and reliability of the communication system. A mux-node receives communication signals from a head-end and forwards the received communication signals to one or more mini-fiber nodes. The connection to the head-end is via a small number of optical fibers and the connections to each of the mini-fiber nodes may be via one or more optical fibers that may provide full duplex communication. The head-end may communicate with the mux-node using digital or digital and analog signals. The mini-fiber nodes may combine the signals received from the head-end with loop-back signals used for local media access control prior to forwarding the signals to the end-users. Upstream data are received by the mini-fiber nodes and transmitted to the mux-node.
    Type: Grant
    Filed: November 10, 2008
    Date of Patent: November 9, 2010
    Assignee: AT&T Intellectual Property II, L.P.
    Inventors: Charles D. Combs, Thomas Edward Darcie, Bhavesh N. Desai, Alan H. Gnauck, Xiaolin Lu, Esteban Sandino, Oleh J. Sniezko, Anthony G. Werner, Sheryl Leigh Woodward
  • Publication number: 20100278535
    Abstract: Provided are a wavelength division multiplexing-passive optical network (WDM-PON) in which a reflective semi-conductor optical amplifier (RSOA) is used as each optical transmitter of an optical line termination (OLT) and an optical network unit (ONU) and additional spectrum-sliced light is injected into RSOAs of each of the OLT and the ONU, and a WDM-PON that is combined with time division multiple access (TDMA) technology, by which the number of included ONUs increases and conventional TDMA ONUs can be used.
    Type: Application
    Filed: December 16, 2008
    Publication date: November 4, 2010
    Applicant: Electronics and Telecommunications Research Institute
    Inventor: Byoung Whi Kim
  • Publication number: 20100266284
    Abstract: A bidirectional optical communications network comprises an optical transmission fiber for carrying a downstream signal at a first wavelength and a multiplicity of upstream signals at a second, different wavelength. The fiber is characterized by distributed Raman gain over at least an extended portion of its length. A first terminal, optically coupled to one end of the fiber, includes a first transmitter for generating the downstream signal, a first receiver for detecting the upstream signals, and at least one pump source for generating pump light that provides Raman amplification to either the downstream signal or the upstream signal or both. A multiplicity of second terminals, optically coupled to another end of the fiber, each includes a second transmitter for generating one of the upstream signals, and a second receiver for detecting a downstream sub-signal.
    Type: Application
    Filed: March 19, 2010
    Publication date: October 21, 2010
    Applicant: OFS FITEL, LLC
    Inventor: Benyuan Zhu
  • Publication number: 20100260496
    Abstract: Method and apparatus for operating for operating an optical network including a shared laser array are disclosed. An example apparatus includes include a first plurality of N lasers. Each laser of the first plurality of N lasers is configured to output a respective optical seed signal having a respective wavelength. The example apparatus further includes a first optical coupler coupled with the first plurality of N lasers. In the example embodiment, the first optical coupler is configured to multiplex the respective optical seed signals of the first plurality of N lasers onto a plurality of N optical fibers. In this example, each optical fiber of first plurality of N optical fibers transmits each of the respective optical seed signals produced by the plurality of N lasers to a respective distribution node for distribution to N respective optical network units, where the optical network units use the optical seed signals to seed respective optical transmitters located at the N optical network units.
    Type: Application
    Filed: April 8, 2009
    Publication date: October 14, 2010
    Inventors: Carlo Tosetti, Damiano Rossetti, Alessandro Cavaciuti