Bidirectional Patents (Class 398/72)
  • Patent number: 7668463
    Abstract: The present invention includes method and apparatus for converting optical signals to MWOF signals for transmission to wireless data, audio and/or video terminals in the W-band. Advantageously, there is no need to maintain expensive and complex remote stations because a centralized station performs all the complex processing.
    Type: Grant
    Filed: March 3, 2006
    Date of Patent: February 23, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Xiang Liu, Carsten Metz
  • Patent number: 7660528
    Abstract: One embodiment of the present invention provides a system for mitigating Raman crosstalk between downstream data and video transmission in an Ethernet passive optical network (EPON), wherein the EPON includes an optical line terminal (OLT) and one or more optical network units (ONU's). During operation, the system transmits a data stream from the OLT to the ONU's on a first wavelength that is substantially at 1490 nm. The system also transmits a video signal stream from the OLT to the ONU's on a second wavelength that is substantially at 1550 nm. The system modifies the bit sequence for the data stream to change the power spectral distribution (PSD) for the data stream, thereby reducing power spectral content in the frequency range where significant Raman crosstalk can occur between data and video signal streams.
    Type: Grant
    Filed: May 9, 2006
    Date of Patent: February 9, 2010
    Assignee: Teknovus, Inc.
    Inventors: Ryan E. Hirth, Lowell D. Lamb, Glen Kramer, Benjamin J. Brown
  • Publication number: 20100021164
    Abstract: A system for overlaying an analog broadcast channel in a Wavelength Division Multiplexed Passive Optical Network (WDM-PON). A remote node of the WDM PON includes a MUX/DEMUX for demultiplexing a Wavelength Division Multiplexed (WDM) signal and supplying respective wavelength channels to each one of a plurality of channel fibers; an optical power splitter for supplying the analog broadcast channel to each one of a plurality of distribution paths; and a respective optocoupler connected to each distribution path, each opticoupler coupling the analog broadcast channel into one of the channel fibers. The analog broadcast channel has a wavelength that is outside a wavelength band of the WDM signal. An Optical Network Terminal (ONT), which is connected to one of the channel fibers, includes a triplexer for separating the analog broadcast channel from at least a downlink wavelength channel of the WDM-PON.
    Type: Application
    Filed: December 22, 2008
    Publication date: January 28, 2010
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: Tom LUK, James GOODCHILD, Giovanni MANTO, Richard HABEL
  • Patent number: 7652390
    Abstract: The invention is directed to an optical network terminal (ONT) for use in a passive optical network (PON) that provides reliable battery status reporting and, optionally, remote monitoring and configuration of an uninterruptible power supply (UPS) unit. In particular, the UPS unit provides power to the ONT via a power line and transmits data to the ONT via the power line. Generally, the described invention supports one-way or two-way communication of status, alarm, and configuration signals using a single power line. Specifically, such signals may be transmitted over the power line by inserting a carrier frequency, such as a carrier frequency of approximately 1 MHz, onto the power line. In this manner, the invention may provide a simple battery status monitoring system while also reducing the cost of installation.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: January 26, 2010
    Assignee: Calix Networks, Inc.
    Inventors: Clifford Vrla, Mark Thomas Paulsen, Mark Richard Biegert, Gary Lee Steinkogler
  • Patent number: 7653309
    Abstract: In accordance with the teachings of the present invention, a system and method for distributing traffic in an optical network is provided. In a particular embodiment, an optical network includes an upstream terminal, a distribution node, and a plurality of downstream terminals. The distribution node in the optical network includes a wavelength router configured to receive wavelength division multiplexed (WDM) traffic in a plurality of wavelengths from the upstream terminal, route the traffic in at least one wavelength to a primary power splitter, and route the traffic in a plurality of other wavelengths for distribution to particular downstream terminals. The distribution node also includes a primary power splitter configured to receive the traffic in the at least one wavelength from the wavelength router, split the received traffic in the at least one wavelength into a plurality of copies, and forward the copies for distribution to all of the downstream terminals.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: January 26, 2010
    Assignee: Fujitsu Limited
    Inventors: Martin Bouda, Stephen J. Brolin
  • Patent number: 7653305
    Abstract: The present disclosure is directed to an optical transport system and device that conserves power, provides for efficient transport of photonic signals and is capable to accommodate a number of different nodes. The system and device are implemented with the major components at the nodes to provide easy maintenance. In a first aspect, the disclosure is directed to an optical transport system that provides for low power and efficient transport of photonic signals. The optical transport system can be implemented with a plurality of similar or identical network interface units that correspond with each node of the system. Also disclosed is an optical transport system architecture having an example architecture that includes a primary system and a secondary system, which is redundant to the primary system and is adapted to be operational when the primary system is inactive, or an example architecture that includes just a primary system.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: January 26, 2010
    Assignee: Lockheed Martin Corporation
    Inventor: Brian L. Uhlhorn
  • Publication number: 20090324225
    Abstract: The invention relates to a method for maintaining the compatibility of legacy receivers in network termination units of an optical distributing network structure, especially in a passive optical network, when in the distributing network structure advanced receivers with a multiple of the data rate of the legacy receivers shall be operated too, in which signals for the advanced receivers are transmitted on the same wavelength and using the same physical paths as signals for the legacy receivers, in which, while transmitting signals for the advanced receivers at the same time also signals for the legacy receivers are transmitted, and in which the amplitude of the signals for the advanced receivers compared to the amplitude of the signals for the legacy receivers are chosen such that the signals for the advanced receivers do not block the legacy receivers in the receipt of the signals intended for them.
    Type: Application
    Filed: April 22, 2008
    Publication date: December 31, 2009
    Applicant: Alcatel Lucent
    Inventors: Heinz Krimmel, Thomas Pfeiffer, Lothar Jentsch
  • Patent number: 7639946
    Abstract: A distribution node for an optical network is provided that includes an integrated filter module comprising a first thin-film and a second thin-film coupled to a common substrate and operable to receive a first downstream signal at the substrate comprising at least traffic in a first wavelength and a second wavelength, transmit the traffic in the first wavelength from the first thin-film to a first plurality of downstream terminals, reflect the traffic in the second wavelength to the second thin-film, and transmit at least the traffic in the second wavelength from the second thin-film to a second plurality of downstream terminals. A traffic distributor is operable to receive a second downstream signal comprising at least traffic in a third wavelength and forward the traffic in the third wavelength to the common substrate for distribution to the first plurality and second plurality of downstream terminals.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: December 29, 2009
    Assignee: Fujitsu Limited
    Inventor: Martin Bouda
  • Patent number: 7639949
    Abstract: A TDM PON including: an optical line terminal; a remote node including multiple secondary optical distributors connected to multiple optical network units; and the multiple optical network units generating and outputting a corresponding upstream optical signal. Each of the secondary optical distributors splits an upstream optical signal input from one of the optical network units connected thereto so as to generate split upstream optical signals and transmits one of the upstream optical signals to the optical line terminal, and transmits another upstream optical signal to a different optical network unit.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: December 29, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Dae-Kwang Jung, Seong-Taek Hwang, Jin-Woo Park, Sang-Rok Lee, Seong-Geun Lee
  • Publication number: 20090304388
    Abstract: In the case where, in a WDM-PON system, a high-output optical signal or a pseudo signal for illegal access by a hostile user, or an optical signal with a wavelength which is not assigned from an OLT is input to an ONU-side optical fiber, the quality of communications for other users is possibly affected and a receiver on the station side is possibly destroyed. By providing an optical blocking unit at a position near an ONU-side optical splitter of an optical branching unit, in the case where input of an extraordinary optical signal is detected, an optical route into which the extraordinary optical signal is input is blocked, so that the input of the extraordinary optical signal to an OLT and optical lines shared by plural users can be preliminarily blocked.
    Type: Application
    Filed: June 4, 2009
    Publication date: December 10, 2009
    Inventors: Kazuyori UMEMATSU, Yusuke Yajima, Tsuyoshi Kano, Toshiki Sugawara
  • Patent number: 7630640
    Abstract: An optical communication system which constructs, at low cost, a network that uses Time Division Multiplexing in at least one direction of the communication. The optical communication system includes an optical multiplexer/demultiplexer that mediates communication between a network unit and a plurality of terminal units. The optical multiplexer/demultiplexer regenerates a synchronization clock from a downstream signal light. In addition, the optical multiplexer/demultiplexer adjusts, using the regenerated synchronization clock, the delay times of a plurality of upstream signal lights received from the terminal units. The network unit and the terminal units do not need to control the timing of the upstream signal lights. Thus, the construction costs of the optical communication system are reduced.
    Type: Grant
    Filed: May 15, 2006
    Date of Patent: December 8, 2009
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Masatoshi Kagawa, Hiromi Tsuji
  • Patent number: 7630639
    Abstract: One embodiment of the present invention provides a system that facilitates transmission control in an Ethernet passive optical network, which includes a central node and at least one remote node, and wherein a remote node implements a data-link layer and a physical layer. During operation, the system starts by receiving, at the physical layer of a remote node, a word which is communicated from the data-link layer of the remote node, wherein the word may be a data word or an idle word. The system then delays the word for a pre-determined amount of time before allowing the word to be transmitted by a transmitter, thereby providing time for turning the transmitter on or off. The system also turns the transmitter on or off based on the content of the received words.
    Type: Grant
    Filed: September 14, 2004
    Date of Patent: December 8, 2009
    Assignee: Teknovus, Inc.
    Inventors: Glen Kramer, Edward W. Boyd
  • Patent number: 7630637
    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: August 14, 2006
    Date of Patent: December 8, 2009
    Assignee: Hitachi Communication Technologies, Ltd.
    Inventors: Masahiko Mizutani, Takeshi Shibata, Tohru Kazawa, Yoshihiro Ashi, Masanobu Kobayashi, Masayuki Takase
  • Patent number: 7623786
    Abstract: The present invention is generally drawn to optical network architecture that can include a multi-subscriber optical interface that can service a plurality of subscribers that are located in close proximity relative to one another. For example, the multi-subscriber optical interface can service multiple dwelling units such as an apartment complex that has many different subscribers to the optical network system. Further, the invention can also service subscribers over the same optical waveguide who may have different bandwidth needs, such as businesses, personal/home users and the like.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: November 24, 2009
    Assignee: Enablence USA FTTX Networks, Inc.
    Inventors: Paul F. Whittlesey, Emmanuel A. Vella, James O. Farmer
  • Patent number: 7616892
    Abstract: A contents information delivery method for delivering a desired contents information by transmitting an optical signal from a central station to each of a plurality of user stations via a transmission line includes: a first step (S1) of outputting an optical signal containing the contents information as an optical signal having mutually different wavelengths each assigned for the each user station in advance, in the central station; a second step (S2) of transmitting an optical signal having a plurality of wavelengths outputted via the transmission line in the first step; and a third step (S3), in which each user station receives the optical signal having the wavelength assigned from among the transmitted optical signals, whereby, this simple configuration does not limit the transmission rate, the coding format, or the like in an optical access system, i.e., making it possible to cope with a super-large capacity.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: November 10, 2009
    Assignee: Fujitsu Limited
    Inventors: Yasuo Suzuki, Hiroaki Nakazato
  • Patent number: 7616890
    Abstract: Embodiments of the invention include a method, device an/or system of expanding the operational bandwidth of a communication infrastructure.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: November 10, 2009
    Assignee: Xtend Networks Ltd.
    Inventors: Zeev Orbach, Hillel Weinstein
  • Publication number: 20090274463
    Abstract: This disclosure is directed to devices and methods for facilitating the upgrade of optical networks. An optical network terminal (ONT) that terminates an optical fiber link of an optical network comprises two or more transport engines that each converts data transmitted via different transports to data corresponding to a service. For example, the ONT may include a first transport engine and a second transport engine. The first transport engine converts data received over the optical network via a first transport, e.g., a legacy transport, into data corresponding to a service for one or more subscriber devices. The second transport engine converts the data received over the optical network via a second transport, e.g., a next generation transport, into the data corresponding to the service for the subscriber devices. The ONT is selectively configurable to select one of the first and second transport engines, thereby making the ONT upgrade-resilient.
    Type: Application
    Filed: May 5, 2008
    Publication date: November 5, 2009
    Applicant: Calix, Inc.
    Inventors: Christopher T. Bernard, Charles J. Eddleston
  • Patent number: 7613395
    Abstract: A transmission system for a passive optical network comprises a shared optical transmission apparatus, a shared electrical interface apparatus and a plurality of transmission convergence termination units. The shared optical transmission apparatus is configured for being coupled to an optical line termination unit via an optical fiber. The shared electrical interface apparatus is coupled to the shared optical transmission apparatus. The plurality of transmission convergence termination units is coupled to the shared electrical interface apparatus. Each one of the transmission convergence termination units is configured for selectively controlling the shared electrical interface apparatus.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: November 3, 2009
    Assignee: Alcatel Lucent
    Inventors: Jonathan Huffman, Ray Tyrrell, Hal Thorne, Dirk Corsus, Duane Remein, David Eckard, Travis Lentz
  • Patent number: 7609966
    Abstract: An optical communication system includes an optical ring that couples a hub node and a plurality of local nodes. The hub node is capable of receiving traffic over the optical ring from the plurality of local nodes on a transmitting wavelength and transmitting traffic over the optical ring to the local nodes on a receiving wavelength. At least one local node is capable of adding traffic to the optical ring by determining whether any other local node is transmitting at the transmitting wavelength and, in response to determining that no other local node is transmitting at the transmitting wavelength, transmitting a request message to the hub node requesting use of the transmitting wavelength. The local node adding traffic is further capable of receiving a grant message from the hub node and, in response to receiving the grant message from the hub node, transmitting traffic at the transmitting wavelength.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: October 27, 2009
    Assignee: Fujitsu Limited
    Inventors: Ashwin Anil Gumaste, Susumu Kinoshita, Raghu Ramireddy Valisammagari
  • Patent number: 7609967
    Abstract: An apparatus automatically maintains bi-directional communication between an optical network unit (ONU) and a central office (CO) in a passive optical network (PON) when the CO changes from a first PON mode to a second PON mode. The apparatus senses a PON mode relating to downstream data flow from the CO to the ONU; and upon detecting a change in the PON mode from the first PON mode to the second PON mode, synchronizes the ONU to operate according to the downstream and upstream configurations of the second PON mode.
    Type: Grant
    Filed: April 10, 2006
    Date of Patent: October 27, 2009
    Assignee: Broadlight Ltd.
    Inventors: Simon Hochbaum, Eli Elmoalem, Doron Tal, David Ivancovsky
  • Patent number: 7606492
    Abstract: An optical fiber network can include an outdoor bandwidth transforming node that can be positioned in close proximity to the subscribers of an optical fiber network. The outdoor bandwidth transforming node does not require active cooling and heating devices that control the temperature surrounding the bandwidth transforming node. The bandwidth transforming node can adjust a subscriber's bandwidth on a subscription basis or on an as-needed basis. The bandwidth transforming node can also offer data bandwidth to the subscriber in preassigned increments. Additionally, the bandwidth transforming node lends itself to efficient upgrading that can be performed entirely on the network side. The bandwidth transforming node can also provide high speed symmetrical data transmission. Further, the bandwidth transforming node can increase upstream and downstream bandwidth and transmission speed by propagating data signals at different wavelengths.
    Type: Grant
    Filed: October 5, 2006
    Date of Patent: October 20, 2009
    Assignee: Enablence USA FTTX Networks Inc.
    Inventors: James O. Farmer, Paul F. Whittlesey, Patrick W. Quinn, John J. Kenny, Emmanuel A. Vella, Thomas A. Tighe
  • Patent number: 7606489
    Abstract: A highly reliable, carrier class passive optical network and associated devices which employs multiple instances of operating software in host systems, as well as mechanisms to automatically determine whether an individual OLT device has entered or left the system without disruption to overall system operation.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: October 20, 2009
    Assignee: Cortina Systes, Inc.
    Inventors: Charles Chen, Yibin Yang
  • Patent number: 7606490
    Abstract: In an optical data network, such as a passive optical network (PON), an optical line terminator (OLT) measures the strengths of one or more signals received from the optical network units (ONUs) and generates a message containing an indication responsive to the measured signal strength. The OLT transmits the message to the ONUs. The ONUs generate packets having preambles of a length responsive to the indication contained in the message.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: October 20, 2009
    Assignee: Alcatel Lucent
    Inventors: Rodger Dalton, Eugen H. Ruegg, Jason Teeter
  • Patent number: 7603036
    Abstract: A method includes transmitting, at a first wavelength, a first configuration message on the PON including a first transmitter interface number and transmitting, at a second wavelength, a second configuration message on the PON including a second transmitter interface number. The method further includes receiving a configuration response message from a first set of ONUs that comprises the first transmitter interface number and from a second set of ONUs that comprises the second transmitter interface, associating the first set of ONUs with the first wavelength and the second set of ONUs with the second wavelength, and transmitting downstream traffic destined for any ONU in the first set of ONUs at the first wavelength and transmitting downstream traffic for any ONU in the second set of ONUs at the second wavelength.
    Type: Grant
    Filed: October 25, 2006
    Date of Patent: October 13, 2009
    Assignee: Fujitsu Limited
    Inventors: Paparao Palacharla, Martin Bouda, Takao Naito
  • Patent number: 7599623
    Abstract: An apparatus or corresponding method of managing Plain Old Telephone Service (POTS) lines in a Passive Optical Network (PON) to prevent an alarm system from generating an alarm during a software upgrade or maintenance of an Optical Network Terminal (ONT), Optical Line Terminal (OLT), or PON while maintaining the effectiveness of the alarm system. The ONT may store data related to a POTS line in nonvolatile memory. The ONT may activate the POTS line based on the data from the nonvolatile memory in an event of interruption in communications with an OLT prior to reestablishing communications with the OLT. The interruption in communications may be caused by an ONT reboot to complete an installation of a software upgrade. The ONT may energize the POTS line with a voltage in response to activating the POTS line to prevent the alarm system from generating the alarm.
    Type: Grant
    Filed: February 10, 2006
    Date of Patent: October 6, 2009
    Assignee: Tellabs Petaluma, Inc.
    Inventors: John A. Stock, Douglas A. Atkinson, Raul F. Fernandez, Thomas E. Conklin, Marc R. Bernard
  • Patent number: 7599624
    Abstract: A channel switching function is added to a wavelength division multiplexing passive optical network (WDM-PON) system, which is an access optical network system, and the potential transmission rate is increased by combining wide wavelength tunable lasers and a time division multiplexing (TDM) data structure and properly using the necessary optical components. In addition, when the wavelength of a light source or an arrayed waveguide grating (AWG) changes, the wavelength is traced and the magnitude of a transmitted signal is maximized without an additional detour line using a loop-back network structure. Furthermore, fewer thermo-electric controllers (TECs) are required for stabilizing the temperature of an optical line terminal (OLT) using wavelength tunable lasers, each laser electrically changing its wavelength.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: October 6, 2009
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sahng Gi Park, Su Hwan Oh, Kwang Seong Choi, Moon Ho Park, Yong Soon Baek, Kwang Ryong Oh
  • Patent number: 7599622
    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 3, 2007
    Date of Patent: October 6, 2009
    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: 7596317
    Abstract: An optical network system includes a central office (CO) comprising an A-band BLS to be injected into a light source for downstream signals, an A-band BLS coupling device for coupling the A-band BLS, a first wavelength-division multiplexer/demultiplexer connected to the A-band BLS coupling device for multiplexing/demultiplexing, and a plurality of first optical transceivers connected to the first wavelength-division multiplexer/demultiplexer; a remote node (RN) comprising a B-band BLS coupling device and a second wavelength-division multiplexer/demultiplexer connected to the B-band BLS coupling device for multiplexing/demultiplexing, and being connected to the CO through an optical fiber; and a plurality of optical network terminations (ONTs) including a plurality of second optical transceivers connected to the second wavelength-division multiplexer/demultiplexer, wherein either the RN or one of the plurality of ONTs further includes a B-band BLS to be injected to a light source for upstream signals.
    Type: Grant
    Filed: May 10, 2007
    Date of Patent: September 29, 2009
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Chang-Hee Lee, Sang-Mook Lee, Min-Hwan Kim
  • Patent number: 7596801
    Abstract: Systems and methods are disclosed for providing reverse signals from a plurality of DHCTs to a downstream modulator that is located in the headend facility. The present invention includes a single wire return device (SWRD) that receives RF modulated signals, dynamically determines the address of the associated modulator, and converts the signals into Ethernet signals. The Ethernet signals are subsequently provided to the headend facility via fiber cable.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: September 29, 2009
    Assignee: Scientific-Atlanta, Inc.
    Inventors: William E. Wall, William C. Versteeg
  • Patent number: 7596319
    Abstract: A wavelength division multiplexing-passive optical network (WDM-PON) system includes a light source provider configured to wavelength-division-multiplex a laser light source of a wavelength allotted to each subscriber and optical-power-divide the multiplexed light source, a plurality of optical line terminals each configured to transmit a light source for upward signal with the power-divided light source and convert an upward optical signal into an electric signal, a plurality of optical network units each configured to convert the light source for upward signal into the upward optical signal, and a multiplexer/demultiplexer configured to separate the signal source for upward signal transmitted from the optical line termination in each subscriber or to multiplex the upward optical signal for each subscriber transmitted from the optical network unit so as to transmit the multiplexed signal into the optical line terminal.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: September 29, 2009
    Assignee: KT Corporation
    Inventors: Soo Jin Park, Kil Ho Song
  • Patent number: 7593638
    Abstract: A method and system for ensuring confidentiality of signal transmission in a point-to-multi point data transmission network like Ether net passive optical network, including at least one hub, at least one transmission medium and at least one station connected to the hub via the transmission medium. When an upstream signal is transmitted from a first station, the upstream signal is reflected by at least one disturbing reflector for producing a disturbing reflection. The disturbing reflection combines with a second reflection of the upstream signal and renders the second reflection undependable by a second station.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: September 22, 2009
    Inventors: Olli-Pekka Pohjola, Ari Tervonen
  • Patent number: 7593647
    Abstract: An optical transmitter has a resonance wavelength characteristic that varies with the refractive index of the optical transmitter. The optical transmitter receives a narrow band injected wavelength signal from an incoherent light source. The controller substantially matches a resonant wavelength of the optical transmitter to the wavelength of the injected wavelength signal by changing the refractive index of the optical transmitter to substantially match the resonant wavelength of the optical transmitter and the wavelength of the injected wavelength signal. A detector measures a parameter of the optical transmitter to provide a feedback signal to a controller to determine when the resonant wavelength of the optical transmitter and the wavelength of the injected wavelength signal are substantially matched.
    Type: Grant
    Filed: April 22, 2003
    Date of Patent: September 22, 2009
    Assignee: Novera Optics, Inc.
    Inventors: Chang-Hee Lee, Kwang-Uk Chu, Bong-Soo Kim
  • Patent number: 7593639
    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. The invention operates independently of a legacy upstream transmission timing scheme so that the legacy upstream transmission timing scheme can remain effective in preventing data collisions. In other embodiments, the present invention allows for less complex hardware for subscribers that are not taking data services. Further, an optical signal present line in combination with a driver may be employed in order to reduce the amount of hardware in a laser transceiver node.
    Type: Grant
    Filed: January 16, 2007
    Date of Patent: September 22, 2009
    Assignee: Enablence USA FTTX Networks Inc.
    Inventors: James O. Farmer, John J. Kenny, Patrick W. Quinn, Deven J. Anthony
  • Publication number: 20090220231
    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.
    Type: Application
    Filed: October 23, 2008
    Publication date: September 3, 2009
    Applicant: ADC TELECOMMUNICATIONS, INC.
    Inventors: Steven C. Zimmel, Timothy G. Badar, Trevor D. Smith
  • Publication number: 20090220230
    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.
    Type: Application
    Filed: May 8, 2007
    Publication date: September 3, 2009
    Inventors: Byoung-Whi Kim, Mahn-Yong Park, Seung-Hyun Cho, Woo-Ram Lee
  • Patent number: 7583896
    Abstract: An optical transmitter of an optical-wireless hybrid transmission system according to the invention outputs a first single-mode optical signal (center frequency: fC1) to an optical receiver, generates a polarization-coupled optical signal by orthogonal-polarization-coupling a second single-mode optical signal (center frequency: fC2) with a third single-mode optical signal (center frequency: fC3) so as to give the two waves orthogonal polarization directions and the same optical power, and transmits the generated polarization-coupled optical signal to a base station as an optical carrier signal. The optical receiver couples a modulated optical signal transmitted from the base station with the optical signal output from the optical transmitter, demodulates an electrical signal having intermediate frequencies fIF1 and fIF2 that is obtained by photodecting a resulting coupled optical signal, and generates transmit-data by filtering a resulting output signal.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: September 1, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tomohiro Taniguchi, Naoya Sakurai
  • Patent number: 7583897
    Abstract: A modification to a cable modem termination system (CMTS) can include instructing the CMTS to ignore or skip steps of its timing algorithm so that upstream cable modem signals are controlled only by the upstream protocol of the optical network system. According to another exemplary aspect, a time stamp can be added to the upstream cable modem signals so that the CTMS timing scheme can be used. This time stamp can be used in the data service hub to adjust for the delays that occur while the upstream cable modem signals are sent across the optical network. Another adjustment of the CMTS timing scheme can include using less than a total number of miniature time slots for upstream cable modem transmissions. According to another exemplary aspect, a cable modem termination system can be positioned within a laser transceiver node or a subscriber optical interface.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: September 1, 2009
    Assignee: Enablence USA FTTx Networks Inc.
    Inventors: James O. Farmer, Stephen A. Thomas, Patrick Quinn
  • Publication number: 20090208212
    Abstract: Provided is a bidirectional wavelength division multiplexed passive optical network (WDM-PON) which includes a central office (CO) that transmits and receives multiplexed optical signals, a remote node (RN) that communicates with the CO, receives a multiplexed optical signal to demultiplex, and receives a demultiplexed optical signal to multiplex, an optical network unit (ONU) that transmits and receives demultiplexed optical signals to and from the RN, operational and protective backbone optical fibers that connect the CO to the RN, and operational and protective distribution optical fibers that connect the RN to the ONU.
    Type: Application
    Filed: August 4, 2008
    Publication date: August 20, 2009
    Inventors: Kwan-Il Lee, Sang-Bae Lee
  • Patent number: 7577362
    Abstract: An optical access network method, an optical access network and an optical switch for an optical access network, capable of solving all the three problems in the conventional GE-PON: transmission distance problem, security problem and communication interference problem. The optical access network comprises an OLT, a plurality of ONUs and one or more stages of optical switches, which are connected one another. In the direction from the OLT to the ONU, each frame (packet) transmitted from the OLT to one of the ONUs is checked so that only the destination ONU specified in the frame (packet) is connected to the OLT. In the direction from the ONU to the OLT, a control message transmitted from the OLT to one of the ONUs is checked so that only one ONU which has been given a transmission allowance from the OLT is connected to the OLT with respect to each frame (packet).
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: August 18, 2009
    Assignee: NEC Communication Systems Ltd.
    Inventors: Hiroyuki Kasai, Toshinori Tsuboi, Hiromi Ueda, Takumi Nomura, Hirokazu Kobayashi, Kunitetsu Makino, Hiroyuki Endo
  • Publication number: 20090196612
    Abstract: The present invention relates to an optical modulation method and optical modulation system of a wavelength locked Fabry Perot-Laser Diode (FP-LD) by injecting a broadband light source (BLS) using mutual injection of FP-LDs. More specifically, the present invention relates to a novel modulation technology which embodies a wavelength locked FP-LD capable of being used as an economic light source in an optical network based on a wavelength-division multiplexing passive optical network (WDM-PON).
    Type: Application
    Filed: November 8, 2005
    Publication date: August 6, 2009
    Inventors: Chang-Hee Lee, Ki-Man Choi
  • Publication number: 20090185807
    Abstract: Disclosed is a wavelength division multiplexing passive optical network for simultaneously providing a broadcasting service and a data service by employing a broadband light source, which uses mutually injected Fabry-Perot laser diodes, as well as a central office used for the same.
    Type: Application
    Filed: September 19, 2006
    Publication date: July 23, 2009
    Inventors: Chang-Hee Lee, Jung-Hyung Moon, Ki-Man Choi
  • Patent number: 7558477
    Abstract: A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON). The communication recovering system can recover fault of optical fibers between the central office and the remote nodes without additional optical fibers by grouping two remote nodes and employing AWGs having periodic transmission characteristics, and can also simply and rapidly recover such a fault with minimal optical loss using 1×N structure of the AWGs and On-Off optical switches, although protection optical fibers are additionally installed therein. The communication recovering system has advantages in that it can simplify network structure, be cost-effectively implemented, reduce optical loss, and rapidly perform protection of optical fiber fault.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: July 7, 2009
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yun Chur Chung, Eui Seung Son, Kyung Woo Lim, Kwan Hee Han
  • Patent number: 7558484
    Abstract: The present invention provides a kind of ultra-wide band wireless system, which changes the previous electronic structure for ultra-wide band pulse generator, and uses light to generate pulse signal, transformed by microwave differentiator to Gaussian monocycle pulse transmission signal, the derived pulse signal can provide several GHz bandwidth to transmit fast speed information, and further complete the new ultra-wide band wireless system. It reduces the complexity of electronic system and enhances output signal quality by means of light property, with considerable leading advantage. And the signal generated by this system has broader band and no infringe property, its 10 dB band falls within the range prescribed by the Federal Communication Committee of United States (FCC), successfully realizing the ultra wide band fiberoptic wireless collection network system, and further attaining the goal of seamless communication collection.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: July 7, 2009
    Assignee: Chang Gung Memorial University
    Inventors: Wen-Piao Lin, Jun-Yu Chen
  • Patent number: 7555228
    Abstract: An optical line termination comprises a DC current load, power measurement circuitry, upstream data path circuitry and current mirror circuitry. The current mirror circuitry is connected between the DC current load, the power measurement circuitry and the upstream data path circuitry. The DC current load is connected in parallel with a photodiode of the upstream data path circuitry. The DC current load exhibits a substantially fixed load. The current mirror provides a copy of an aggregate current to the power measurement circuitry. The aggregate current is a summation of a current draw by the DC current load and a current draw by the photodiode. The power measurement circuitry is configured for outputting a power level dependent upon the aggregate current. Accordingly, the optical line termination provides for a non-intrusive solution for measuring optical input power and, thereby, enables the measured optical power to be monitored.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: June 30, 2009
    Assignee: Alcatel Lucent
    Inventors: Eugen H. Ruegg, Richard C. Stamey, Jason T. Teeter
  • Patent number: 7555215
    Abstract: A dual structure for a multiplexing section extended to an OSU is obtained without adding a dynamic function, such as an optical switch, to a W-MULDEM. The W-MULDEM of an optical wavelength division multiplexing access system divides, among ports corresponding to the individual ONUs, downstream optical signals having wavelengths ?d1 to ?dn, which are received along a current-use optical fiber, or downstream optical signals having wavelengths ?d1+?? to ?dn+??, which are received along a redundant optical fiber. The W-MULDEM also multiplexes, for the port that corresponds to the current-use optical fiber or the redundant optical fiber, upstream optical signals having wavelengths ?u1 to ?un or wavelengths ?u1+?? to ?un+??, which are received along optical fibers corresponding to the ONUs. A wavelength difference between the downstream optical signal and the upstream optical signal that are consonant with each ONU is defined as an integer times the FSR of an AWG.
    Type: Grant
    Filed: May 28, 2004
    Date of Patent: June 30, 2009
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hirotaka Nakamura, Junichi Kani, Hiroo Suzuki, Mitsuhiro Teshima, Ukyo Yamaguchi, Hidetaka Onishi, Katsumi Iwatsuki
  • Patent number: 7551854
    Abstract: To inform a location of a caller to the other party in an IP phone system, a wireless IC tag preserving unique ID information is attached to an optical connector of a user connection port. The relations between locations of the optical connectors and ID information of corresponding wireless IC tags are stored in a port control database. An IC tag reader in an optical network unit (ONU) reads the ID information in the wireless IC tag attached to the optical connector to which the ONU is connected. When an emergency call is initialed, the ONU transmits destination information of the emergency call and the ID information of the wireless IC tag to a central station. A control terminal in the central station compares the ID information of the wireless IC tag against the port control database to determine a location of the optical connector. The central station adds the determined location information to the destination information of the emergency call and transmits the information to an IP network.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: June 23, 2009
    Assignee: KDDI Corporation
    Inventors: Yukio Horiuchi, Noboru Edagawa
  • Patent number: 7546036
    Abstract: In accordance with the teachings of the present invention, a hybrid passive optical network using shared wavelengths is provided. In a particular embodiment, a system for communicating optical signals over a network includes an upstream terminal. The upstream terminal includes a signal source operable to transmit a downstream signal comprising at least traffic in a first wavelength and traffic in a second wavelength. The upstream terminal is operable to receive upstream traffic in a third wavelength, wherein the third wavelength is shared by a first plurality of downstream terminals and a second plurality of downstream terminals. The system also includes a distribution node comprising a wavelength router. The wavelength router is operable to receive the downstream signal, route the traffic in the first wavelength to the first plurality of downstream terminals, and route the traffic in the second wavelength to the second plurality of downstream terminals.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: June 9, 2009
    Assignee: Fujitsu Limited
    Inventors: Martin Bouda, Takao Naito
  • Patent number: 7529485
    Abstract: A system and method for tuning a broadcast receiver such as a television set with a subscriber optical interface (SOI) that can be located outside a subscriber's premises and can be adjacent to the subscriber's premises. For example, a subscriber optical interface can be mounted on a side of a home which converts optical data and optical video signals received from an optical waveguide to electrical signals. Because of the hardware contained in the subscriber optical interface, any video processing hardware that is present within the subscriber's premises for tuning video programs can be reduced or substantially eliminated without sacrificing a range of services available to a subscriber from a fiber-to-the-home optical network.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: May 5, 2009
    Assignee: Enablence USA FTTX Networks, Inc.
    Inventors: James O. Farmer, Stephen A. Thomas
  • Publication number: 20090103922
    Abstract: Provided is a time division multiplex (TDM)/wavelength division multiple access (WDMA) passive optical network (PON) device. The TDM/WDMA PON device comprises a base station terminal, a wavelength splitter, and a subscriber terminal optical transceiver. The base station terminal comprises a transmitter time-division-multiplexing and simultaneously modulating and outputting a plurality of different wavelength optical signals, an optical circulator transmitting the optical signals output from the transmitter to an optical distribution network and transmitting optical signals received from the optical distribution network to a receiver and the receiver demultiplexing wavelength division multiplexed upstream signals from the optical distribution network through the optical circulator, converting the demultiplexed upstream signals into a plurality of electrical signals, and delivering the electrical signals to an upper layer.
    Type: Application
    Filed: June 25, 2008
    Publication date: April 23, 2009
    Applicant: Electronics & Telecommunications Research Institute
    Inventors: Dong Soo Lee, Bin Yeong Yoon, Bong Tae Kim
  • Patent number: 7522838
    Abstract: In accordance with the teachings of the present invention, distribution components for a wavelength-sharing network are provided. In a particular embodiment, a distribution node for an optical network includes a first distributor operable to receive a first downstream signal comprising at least traffic in a first wavelength and traffic in a second wavelength from an upstream terminal, route the traffic in the first wavelength to a first plurality of downstream terminals, and route the traffic in the second wavelength to a second plurality of downstream terminals. A second distributor is operable to receive a second downstream signal comprising at least traffic in a third wavelength, and forward the traffic in the third wavelength to at least the first plurality of downstream terminals.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: April 21, 2009
    Assignee: Fujitsu Limited
    Inventors: Martin Bouda, Takao Naito