Hybrid Fiber-coax Network Patents (Class 725/129)
  • Publication number: 20040168192
    Abstract: A wireless communications system comprises a first splitter separating at least two signals, a wireless circuit for processing a first signal as a wireless signal and a combiner connected to the wireless circuit and the splitter, combining the two signals and transmitting the signals into a service area. The wireless communications system further comprises a second splitter separating the wireless signal from a second signal, and a transmitter for broadcasting the wireless signal.
    Type: Application
    Filed: February 24, 2003
    Publication date: August 26, 2004
    Inventor: John Sidney Stewart
  • Publication number: 20040163120
    Abstract: A method for communicating information is disclosed wherein a time slot is allocated in a time division multiple access system for a transmission from a subscriber to a headend. Synchronization of a clock of the subscriber with respect to a clock of the headend is enhanced using a message transmitted from the headend to the subscriber which is indicative of an error in a subscriber transmission time with respect to the time slot. A feedback loop process is used to determine at least one of fractional symbol timing correction and carrier phase correction of a transmission from the subscriber to the headend. Filter coefficients are generated at the headend from a ranging signal transmitted from the subscriber to the headend and transmitting the filter coefficients from the headend to the subscriber, the filter coefficients being used by the subscriber to compensate for noise in a transmission from the subscriber to the headend.
    Type: Application
    Filed: February 17, 2004
    Publication date: August 19, 2004
    Applicant: Broadcom Corporation
    Inventors: Theodore F. Rabenko, James C. H. Thi, John D. Horton, Thomas J. Quigley, Lisa V. Denney, Jonathan S. Min, Christopher R. Jones, Henry Samueli, Fang Lu, Feng Chen, Sean F. Nazareth
  • Publication number: 20040163119
    Abstract: A cable modem includes a CPU for controlling the entire cable modem, a PGC, for generating a modem signal with adjusted intensity, a transformer for isolating the PGC from a next stage, a low pass filter for filtering off a high-frequency component, and a selecting circuit for selectively transferring the output signal form the low pass filter to a network. In particular, the cable modem of the invention is advantageous for preventing an up-stream signal of the cable modem from transferring to an HFC network and for preventing the entire network to be shut down when an internal circuit operates abnormally.
    Type: Application
    Filed: February 10, 2004
    Publication date: August 19, 2004
    Inventor: Shin-Woong Kay
  • Publication number: 20040163128
    Abstract: A network interface device located at a customer's premises includes an external interface that receives a plurality of telecommunication services via a fiber optic connection from a telecommunication service provider. The services are received using Internet Protocol. The network interface device also includes at least two distinct internal interfaces that distribute the plurality of telecommunication services to at least two distinct internal transport media. The network interface device also includes a processor that is programmed to receive combined signals comprising the telecommunication services from the external interface, process the combined signals into separate signals representative of distinct telecommunication services, and map each of the separate signals to separate ones of the at least two distinct internal interfaces for distribution at the customer's premises via the internal transport media.
    Type: Application
    Filed: November 17, 2003
    Publication date: August 19, 2004
    Applicant: Qwest Communications International Inc.
    Inventors: Bruce A. Phillips, Steven M. Casey, Donald L. Brodigan
  • Patent number: 6771909
    Abstract: A cable television system (100) having forward and reverse paths includes, in the reverse path, a digital optical transmitter (200) for receiving an RF signal, converting it to a digital signal, and adding a digital pilot tone thereto. A laser is driven in accordance with the summed digital signal to generate a digital optical signal representative of the pilot tone and the RF signal. The cable television system (100) also includes an optical receiver (305) for receiving the digital optical signal and recovering therefrom the RF signal and the pilot tone. The optical transmitter (200) and receiver (305) are coupled by fiber optic communication media (110).
    Type: Grant
    Filed: October 17, 2002
    Date of Patent: August 3, 2004
    Assignee: Scientific-Atlanta, Inc.
    Inventors: Forrest M. Farhan, Alberto P. Gaibazzi
  • Publication number: 20040133920
    Abstract: Provided is a digital broadcast system that receives digital broadcast services on a passive optical network (PON). The data separator separates a signal input thereinto from the outside into an Ethernet frame for data service and an Ethernet frame for digital broadcast service. The Ethernet switch transmits the Ethernet frame for data service to an optical network terminal (ONT) provided in the user's home according to header information of the Ethernet frame for data service. The channel request processor receives the user's channel selection request information and user identification (ID) information from the ONT. The digital broadcast processor transmits the Ethernet frame for digital broadcast service, corresponding to the digital broadcast channel selected by the user, to the user's ONT, by using a part of bandwidth assigned for an existing line.
    Type: Application
    Filed: December 17, 2003
    Publication date: July 8, 2004
    Inventors: Yongtae Kim, Kang Bok Lee, Heyung Sub Lee, Hyeong Ho Lee
  • Publication number: 20040060073
    Abstract: A method and system for automated provisioning of hybrid fiber coax (HFC) network elements operable for communicating telephony, data, and video signals with customer-premises equipment of a subscriber includes a database and an online provisioning application link (OPAL). The database is operable for storing data indicative of the configuration of the network elements and the customer-premises equipment, and for storing data indicative of assigned capacity of the network elements. The OPAL is operable with the database for provisioning network elements with the customer-premises equipment of the subscriber based on the assigned capacity of the network elements in order to enable communication of telephony, data, and video signals between the HFC network and the customer-premises equipment of the subscriber.
    Type: Application
    Filed: May 8, 2001
    Publication date: March 25, 2004
    Inventors: Harvey R. Bialk, Anil Kumar Khanna, Jyoti A. Kulkarni, Paul E. Schauer
  • Publication number: 20040045037
    Abstract: A distributed cable modem termination system (CMTS) in a hybrid fiber/coaxial (HFC) plant. The distributed CMTS comprises a network layer, at least one media access control layer, and at least one physical layer. The media access control layer implements a media access control chip. The media access control chip interfaces with the physical layer to provide timing to maintain components within the physical layer. At least one physical layer is connected to a respective at least one media access control layer. The network layer, media access control layer, and physical layer each function as separate modules. The media access control chip does not require packet level media access control functions to be implemented in the same physical location. This enables the network layer to be in a separate component location of the HFC plant from the at least one media access control layer and the at least one physical layer, yet physically connected throughout the HFC plant.
    Type: Application
    Filed: August 27, 2002
    Publication date: March 4, 2004
    Applicant: Broadcom Corporation
    Inventors: Scott Andrew Cummings, Joel I. Danzig, Paul Eugene Burrell
  • Publication number: 20040045033
    Abstract: A distributed cable modem termination system (CMTS) in a hybrid fiber/coaxial (HFC) plant. The distributed CMTS comprises a network layer, at least one media access control layer, and at least one physical layer. The media access control layer implements a media access control chip. The media access control chip interfaces with the physical layer to provide timing to maintain components within the physical layer. The network layer, media access control layer, and physical layer each function as separate modules. The media access control chip provides the packet level media access control functions, and thus, does not require packet level media access control functions to be implemented in the same physical location. The media access control chip also provides a timing offset feature for handling time delays between the media access layer and the physical layer.
    Type: Application
    Filed: August 27, 2002
    Publication date: March 4, 2004
    Applicant: Broadcom Corporation
    Inventors: Scott A. Cummings, Joel I Danzig, Paul E. Burrell
  • Publication number: 20040045035
    Abstract: A distributed CMTS in a hybrid fiber/coaxial (HFC) plant. The distributed CMTS comprises at least one network layer, at least one media access control layer, and one or more physical layers. The at least one network layer, at least one media access control layer and one or more physical layers each function as separate modules, enabling them to be in separate locations, yet physically connected, throughout the HFC plant.
    Type: Application
    Filed: August 27, 2002
    Publication date: March 4, 2004
    Applicant: Broadcom Corporation
    Inventors: Scott Andrew Cummings, Joel I. Danzig, Paul Eugene Burrell
  • Publication number: 20040031059
    Abstract: A hybrid fiber coax (HFC) network management method and system for use in a broadband network having a hybrid fiber coax (HFC) network provided with network elements operable for communicating telephony, data, and video signals with customer-premises equipment of a subscriber includes an HFC network manager for monitoring status and configuration of the network elements and the customer-premises equipment. A service, design, and inventory (SDI) database is operable with the HFC network manager for storing data indicative of the configuration of the network elements and the customer-premises equipment. A fault manager having an alarm visualization tool is operable with the HFC network manager and the SDI database for generating visual displays of the status and configuration of the network elements and the customer-premises equipment.
    Type: Application
    Filed: May 8, 2001
    Publication date: February 12, 2004
    Inventors: Harvey R. Bialk, Jyoti A. Kulkarni, Paul E. Schauer
  • Patent number: 6687907
    Abstract: Detecting tampering of an incoming cable to which a network interface unit (NIU) is connected by testing for the reflected signal that is present when the signal being transmitted to the head end is not connected to a properly terminated coaxial cable. In particular, by comparing the phase of the transmitted signal from the NIU with that of the reflected signal, a distinction can be made between a signal that travels many feet before being reflected back and a signal that reflects back right or near the connector of the NIU. Only the latter is used as a stimulus to indicate tampering since the first is likely caused by cable personnel disconnecting the cable further into the network. The key difference between the two types of reflected signals is the time delay of the reflect signal with respect to the transmitted signal from the NIU.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: February 3, 2004
    Assignee: Lucent Technologies Inc.
    Inventor: Edward J Bortolini
  • Patent number: 6674967
    Abstract: A fiber-to-the-home (FTTH) system transmits forward and reverse optical signals, such as video, voice, and data signals, via optical fiber, and includes a plurality of home network units. The home network units include an FTTH optical receiver for receiving at least one of the video, voice, and data signals. A triplexer distinguishes and separates the video, voice, and data signals, wherein the video signals have a first wavelength and the voice and data signals have a second wavelength. The voice and data signals are provided to the home network unit for further processing. The triplexer provides an electrical signal to the amplifier stages. The amplifier stages include a preamplifier stage and a postamplifier stage. A gain control circuit automatically adjusts the gain of the video signal based upon the input power level to the FTTH optical receiver. Additionally, a tilt network performs level compensation for externally located coaxial cable.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: January 6, 2004
    Assignee: Scientific-Atlanta, Inc.
    Inventors: John Skrobko, Robert R. Riggsby
  • Publication number: 20030237099
    Abstract: A method is disclosed for delivering multimedia data streams to subscribers of a data distribution network in which a first number of data streams of different programs are fed into a head end and thence to different lower-level distribution points, in which these data streams are converted for transmission by an analog frequency-division multiplexing technique to a number of home terminations. Each of the terminals connected to the home termination can select one or more programs by selection of a frequency channel, and output this program or these programs to a user. In addition to the first number of data streams, the lower-level distribution points each receive a second number of data streams, and they retransmit data streams of this second number of data streams, together with data streams of the first number of data streams, as analog signals over given frequency channels to the respective home terminations connected thereto.
    Type: Application
    Filed: June 18, 2003
    Publication date: December 25, 2003
    Applicant: ALCATEL
    Inventors: Hartmut Weik, Markus Jenisch
  • Patent number: 6662135
    Abstract: A method and apparatus for performing an operability test on a communications system device such as a cable modem is provided. The testing method comprises the steps of providing a set of output test data to the communications system device being tested, and generating an output signal with the device in a manner that is responsive to the output test data. In the case of a cable modem, the output signal is generated by the modem's modulator. The output signal is then provided as an input to a reflective mixer which generates a reflected signal in response to the output signal and directs it back into the communications system device being tested. The communications device can then use the reflected signal to generate a set of input test data that can be compared to the output test data to check the accuracy of the device's operation.
    Type: Grant
    Filed: December 9, 1998
    Date of Patent: December 9, 2003
    Assignee: 3Com Corporation
    Inventors: Lawrence M. Burns, Ravi Ramachandran
  • Patent number: 6662367
    Abstract: A head end terminal for a communication system using multicarrier modulation is described. The head end terminal includes a multicarrier modem adapted to receive upstream signals and to demodulate the upstream signals modulated on a plurality of orthogonal carriers in a first frequency bandwidth, the multicarrier modem including a polyphase filter adapted to selectively filter the received upstream signal to provide protection against narrowband ingress for the modulated orthogonal carriers and allow for scalable bandwidth usage in the upstream transmission, and a controller operatively connected to the multicarrier modem for controlling receipt of signals.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: December 9, 2003
    Assignee: ADC Telecommunications, Inc.
    Inventors: Mark J. Dapper, Michael J. Geile
  • Patent number: 6654958
    Abstract: A CATV system is provided that includes a head-end with laser transmitters to provide data to a multitude of nodes through a forward optical network tree. The nodes convert the optical signals into electrical signals and retransmit the television and data signals through a coaxial network tree to customer interface units (CIUs). The nodes include respective controllers which identify status signals from the equipment of the nodes and transmit the status signals and a reference signal to the head-end controller for display on a display of the head-end controller. The reference signal allows monitoring that the return optical transmitter and network are operating correctly and allows the return signals from the nodes to be aligned. The status signals from the nodes include laser operation, laser bias current and laser power output for the laser transmitters of the nodes.
    Type: Grant
    Filed: September 18, 1998
    Date of Patent: November 25, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Douglas K. Roberts, Gary F. Chandler, Horacio G. Facca
  • Publication number: 20030163831
    Abstract: A hand-held cable communicator unit for technicians that enables voice and data communications across a cable network. The communicator includes a cable connector, a diplex filter, a transceiver circuit, an audio circuit and a control circuit. The transceiver circuit tunes to selected downstream and upstream channels signals. The audio circuit enables bidirectional voice communications using the selected channels signals via the cable network. The control circuit establishes a communication link and initiates and terminates communications. A communication system for field technicians of a cable network includes at least one communicator and a central communicator located at a point of distribution of the cable network. The central communicator includes transceivers, a switch matrix and a controller. Each central transceiver establishes a communication link with any linked communicator. The switch matrix forwards upstream and downstream communications between linked communicators.
    Type: Application
    Filed: October 18, 2002
    Publication date: August 28, 2003
    Inventors: Donald T. Gall, David M. Pangrac
  • Publication number: 20030154497
    Abstract: An optical coaxial hybrid transmission system capable of quickly achieving high-speed Internet access at low cost without making any substantial changes to a transmission path of the existing system is provided. In this system, m-channel communications signals having frequencies of f1 to fm (Hz) corresponding to micro-cells 51 are converted into optical signals having different wavelengths by communications signal optical transmitters 102. These optical signals are wavelength-multiplexed by a communications signal wavelength multiplexer 103, and then wavelength-multiplexed by a video/communications signal wavelength multiplexer 104 with an optical signal modulated with a video signal. The resultant wavelength-multiplexed optical signal is transmitted to a node 30. In the node 30, the wavelength-multiplex optical signal is demultiplexed, and the video signal and the communications signals are frequency-multiplexed for transmission to the corresponding micro-cells 51.
    Type: Application
    Filed: February 3, 2003
    Publication date: August 14, 2003
    Inventors: Kouichi Masuda, Hiroyuki Sasai
  • Publication number: 20030140353
    Abstract: A digital headend architecture and full service network are provided to selectively demodulate and decode a variety of digital and analog feeds into baseband signals or pass digital programming through the headend. In accordance with one embodiment, the head end is provided with digital-turn-around capability to allow precompressed signals to passed through the head end with out any decompress or decoding into baseband signals. The head end includes at least one receiver for receiving signals sent by satellite, at least one antenna for receiving over-the-air signals as baseband composite video and audio signals, and a decoder connected to the at least one receiver for converting received satellite signals into baseband video and audio signals. At least one MPEG encoder is provided for encoding the baseband video and audio composite signals into multiplexed Single Program Transport Streams (SPTS).
    Type: Application
    Filed: March 3, 2003
    Publication date: July 24, 2003
    Applicant: Qwest Communications International Inc.
    Inventors: Keith F. Hugenberg, Martin William Rau, Atis Ojars Jurka
  • Publication number: 20030140340
    Abstract: A conditional access control apparatus for inserting descrambling messages and impulse authorizations to enable requesting subscribers to utilize requested scrambled content. The apparatus includes a content and asset storage module for storing content and assets, and a pre-encryption module for encrypting content to be stored in said content device. A transport processor inserts stored content into a forward application transport channel (FATC), and a controller interacts with a requesting subscriber and inserts into the FATC descrambling messages and impulse authorizations enabling the requesting subscriber to utilize requested scrambled content.
    Type: Application
    Filed: February 5, 2003
    Publication date: July 24, 2003
    Inventor: Michael C. Bertram
  • Publication number: 20030126614
    Abstract: The present invention provides a system and method for improving the performance of a data communication system, particularly a CATV system, by dividing the functionality of the cable modem termination systems (CMTSs) into functional units, and distributing these functional units among fiber nodes or other locations throughout the data communication system. This approach provides passive return signal paths and their associated benefits.
    Type: Application
    Filed: December 27, 2001
    Publication date: July 3, 2003
    Inventor: Jay G. Staiger
  • Patent number: 6577414
    Abstract: A passive optical network is provided that integrates signals carrying broadcast CATV services into a FTTH/C network that also provides high-speed Internet access and telephony. Essentially all residential telecommunications services are provided in a single network, based on a single fiber and a single simple transceiver in an optical network unit. Multiple services (e.g., analog video, digital video, cable-modem based Internet access) are multiplexed using separate rf subcarriers (subcarrier multiplexing or SCM) and the delivered signals are compatible with existing consumer appliances (e.g., TVs, VCRs, cable modems, etc.).
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: June 10, 2003
    Assignee: Lucent Technologies Inc.
    Inventors: Robert D. Feldman, John A. Stiles, Gordon C. Wilson, Thomas H. Wood
  • Patent number: 6567987
    Abstract: A cable television system (400) includes a transmitter (200) for generating a digital optical signal (204) and a receiver (300) for receiving said digital optical signal and converting it to an analog signal. The transmitter (200) includes a processor (238) for processing inputs and generating a gain/loss parameter which is applied via a gain/loss amplifier (250) to an incoming analog signal (232). The modified digital signal received by the digital optical receiver (300) decodes the applied gain/loss parameter at a converter (325) and applies the information to the output analog signal via a gain/loss amplifier (330).
    Type: Grant
    Filed: February 16, 1999
    Date of Patent: May 20, 2003
    Assignee: Scientific-Atlanta, Inc.
    Inventors: Forrest M. Farhan, Joseph Graham Mobley
  • Patent number: 6560778
    Abstract: There is disclosed a tap device for branching a part of transmission signals running through a transmission line to selectively transmit branched signals to subscriber terminal devices via tap output terminals, in which signal paths for leading the transmission signals to the tap output terminals can easily and securely be shielded. Substrates provided with various circuits and the like are successively fixed to a housing member provided with tap output terminals. The housing member is provided with partition walls for surrounding the signal paths to the tap output terminals from the first substrate and separating relays disposed on the substrate. A shield cover, which can separate wiring patterns for signal input to the relays and wiring patterns for signal output via the relays, is disposed between the first and the second substrates. The second substrate is fixed to the housing member via the shield cover.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: May 6, 2003
    Assignee: Masprodenkoh Kabushikikaisha
    Inventor: Shinji Hasegawa
  • Publication number: 20030079233
    Abstract: An arrangement is provided for consolidating equipment, services, and information and for distributing information from a consolidated information distribution center (CIDC) to a plurality of head ends using spectrally efficient transport. The CIDC generates an optical signal encoded with information of multiple channels aggregated through a multi-level encoding scheme and sends the optical signal to a plurality of head ends via an optical fiber. When a head end receives the optical signal, it decodes the optical signal in multiple stages to produce information of multiple data streams, from which desired data streams are selected.
    Type: Application
    Filed: October 9, 2002
    Publication date: April 24, 2003
    Inventors: Paul J. Matthews, Paul D. Biernacki, Irl N. Duling
  • Patent number: 6546557
    Abstract: A method and system for enhancing digital video transmission to set-top boxes improves the performance of a hybrid analog and digital video transmission system, for example, an AM-VSB QAM video transmission system, by selecting a digital channel map based on the relative magnitude and frequency locations of CSO and CTB distortions and the analog channel frequency plan. A variable interleaver may also be implemented in the video transmission system to further reduce the CSO and CTB distortions.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: April 8, 2003
    Assignee: General Instrument Corporation
    Inventor: Shlomo Ovadia
  • Publication number: 20030066087
    Abstract: A hybrid distributed cable modem termination systems having mini fiber nodes containing CMTS modulators remotely located from the head end. DOCSIS MAC layer components are located at the head end. This lowers cost and allows use of a smaller mFN enclosure. The mFN has A/D converters for DOCSIS upstream traffic and for legacy upstream traffic. A multiplexer using forward error correction combines the legacy and DOCSIS traffic for upstream transmission along a single fiber at rates of approximately 2 Gbps. A splitter at the head end routes legacy traffic to legacy equipment and the DOCSIS traffic to the MAC layer components. A single power supply at the head end can be used to power the mFNs.
    Type: Application
    Filed: September 27, 2002
    Publication date: April 3, 2003
    Inventors: Wilson E. Sawyer, John M. Ulm, David Gingold, Jerald Archambault
  • Publication number: 20030066088
    Abstract: A method of utilizing a bidirectional amplifier in a cable hybrid fiber and coax (HFC) and a cable modem utilizing an upstream signal. The invention provides an upstream pilot signal from the cable modem and automatically controls the gain of the signal so that the headend receives a constant level upstream pilot signal from each terminal. A cable modem for bidirectional services in the HFC network has a saw filter, a mixer & AGC, a LPF, a tuner, a gain controller, a downstream demodulator, an upstream modulator, a media access controller (MAC), a CPU, a programmable attenuator, a pilot signal generator and a switch connecting the tuner and the pilot signal generator under the control of the CPU.
    Type: Application
    Filed: November 8, 2002
    Publication date: April 3, 2003
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Choon-Jae Jung
  • Publication number: 20030063352
    Abstract: A cable television system (100) having forward and reverse paths includes, in the reverse path, a digital optical transmitter (200) for receiving an RF signal, converting it to a digital signal, and adding a digital pilot tone thereto. A laser is driven in accordance with the summed digital signal to generate a digital optical signal representative of the pilot tone and the RF signal. The cable television system (100) also includes an optical receiver (305)for receiving the digital optical signal and recovering therefrom the RF signal and the pilot tone. The optical transmitter (200) and receiver (305) are coupled by fiber optic communication media (110).
    Type: Application
    Filed: October 17, 2002
    Publication date: April 3, 2003
    Inventors: Forrest M. Farhan, Alberto P. Gaibazzi
  • Patent number: 6538781
    Abstract: A system for distributing multimedia information from a central office to a plurality of customer's premises each interconnected to the central office with a dedicated optical fiber includes a switch for transmitting a plurality of optical bands from the central office to each of the subscriber premises. The switch, being located in the central office and controlled by selection signals provided to or by the central office, selects a subset of first signals, either electrical or optical, and blocks others of the signals that are not contained within the subset so that the customer receives only the signals subscribed to by the customer. Each customer's premises has a receiver, coupled to the corresponding dedicated fiber, to detect the subset desired by the customer.
    Type: Grant
    Filed: April 1, 1999
    Date of Patent: March 25, 2003
    Inventors: John Beierle, Jacob Needle, Dimitrios Kokkinos
  • Publication number: 20030056226
    Abstract: The creation of “virtual telephony endpoints” within a subscriber's location allows for diverse types of telephone sets, connected via different types of communication networks (e.g., PSTN, Ethernet, power line connections, etc.), to be grouped together and perform as “extensions” as in the sense of traditional wired telephone networks, with a “virtual” telephone number assigned to each virtual telephony endpoint (VTEP). The grouping of the telephone sets within each VTEP can be configured and continuously re-configured by the subscriber, as can the number of separate VTEPs within a single location.
    Type: Application
    Filed: September 20, 2001
    Publication date: March 20, 2003
    Inventors: David B. Lazarus, Robert C. Stein
  • Publication number: 20030056227
    Abstract: A cable television system (100) includes forward and reverse paths. Reverse path circuitry within an optical node (400) of the system (100) receives reverse analog electrical signals from subscriber equipment (140) and generates therefrom a multiplexed reverse digital optical signal. The reverse digital optical signal is transmitted over a fiber optic cable 420 to a cable television hub (430), the reverse path portion of which includes no active circuitry. The hub (430) multiplexes the reverse digital optical signal with other reverse digital optical signals from other nodes to generate one or more forwarded digital optical signals at a hub output, wherein generation of the one or more forwarded digital optical signals requires only passive devices in the reverse path of the hub (430).
    Type: Application
    Filed: October 22, 2002
    Publication date: March 20, 2003
    Inventors: Fariborz M. Farhan, Douglas E. Brown
  • Publication number: 20030043438
    Abstract: A cable television system (100) having forward and reverse paths includes, in the reverse path, a digital optical transmitter (200) for receiving an RF signal, converting it to a digital signal, and adding a digital pilot tone thereto. A laser is driven in accordance with the summed digital signal to generate a digital optical signal representative of the pilot tone and the RF signal. The cable television system (100) also includes an optical receiver (305)for receiving the digital optical signal and recovering therefrom the RF signal and the pilot tone. The optical transmitter (200) and receiver (305) are coupled by fiber optic communication media (110).
    Type: Application
    Filed: October 30, 2002
    Publication date: March 6, 2003
    Inventors: Forrest M. Farhan, Alberto P. Gaibazzi
  • Patent number: 6523177
    Abstract: A cable television system (100) includes forward and reverse paths. Reverse path circuitry within an optical node (400) of the system (100) receives reverse analog electrical signals from subscriber equipment (140) and generates therefrom a multiplexed reverse digital optical signal. The reverse digital optical signal is transmitted over a fiber optic cable 420 to a cable television hub (430), the reverse path portion of which includes no active circuitry. The hub (430) multiplexes the reverse digital optical signal with other reverse digital optical signals from other nodes to generate one or more forwarded digital optical signals at a hub output, wherein generation of the one or more forwarded digital optical signals requires only passive devices in the reverse path of the hub (430).
    Type: Grant
    Filed: April 1, 1999
    Date of Patent: February 18, 2003
    Assignee: Scientific-Atlanta, Inc.
    Inventor: Douglas E. Brown
  • Publication number: 20030033608
    Abstract: A cable system having a splitter for coupling a drop interface to a cable modem and pass-through to a home interface. The pass-through is provided with an RF module having separate forward and return paths to selectively provide unimpeded, partially impeded and fully impeded cable service in the forward and return paths. Amplifiers in the forward and return paths are controlled to avoid excessive insertion loss and to provide power equalization in the return path to limit ingress noise to the home.
    Type: Application
    Filed: August 10, 2001
    Publication date: February 13, 2003
    Applicant: General Instrument Corporation
    Inventors: Kevin T. Chang, Richard Moore, Jay Strater
  • Patent number: 6519067
    Abstract: A cable television system (100) having forward and reverse paths includes, in the reverse path, a digital optical transmitter (200) for receiving an RF signal, converting it to a digital signal, and adding a digital pilot tone thereto. A laser is driven in accordance with the summed digital signal to generate a digital optical signal representative of the pilot tone and the RF signal. The cable television system (100) also includes an optical receiver (305)for receiving the digital optical signal and recovering therefrom the RF signal and the pilot tone. The optical transmitter (200) and receiver (305) are coupled by fiber optic communication media (110).
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: February 11, 2003
    Assignee: Scientific-Atlanta, Inc.
    Inventors: Forrest M. Farhan, Alberto P. Gaibazzi
  • Publication number: 20030028897
    Abstract: In a hybrid fiber coax (HFC) cable system, data is communicated upstream from user terminals to a headend of the system to realize various interactive services. The user terminals generate analog modulated signals representing the user data, which populate different channels in a reverse passband of the system. In accordance with the invention, the analog modulated signals are transformed to the corresponding digital baseband signals containing the data. The resulting digital baseband signals are optically transmitted to the headend, thereby efficiently utilizing the limited capacity of the fiber optical portion of the HFC cable system.
    Type: Application
    Filed: August 6, 2001
    Publication date: February 6, 2003
    Inventor: Paul D. Brooks
  • Publication number: 20030028898
    Abstract: A method of allocating power among a plurality of signals, at least two of the signals employing different signal formats, located on different channels of the return path of a cable data network, divides a total power available for the signals on the return path in accordance with a minimum value of an average BER for all the signals and allocates power to each of the signals in accordance therewith. Specifically, a number of parameters are obtained including modulation type and symbol rate for each signal format employed on the return path, the AWGN noise floor across the reverse link, the nominal maximum available RF power for transmitting signals on the reverse path. A predetermined BER expression for each of the modulation types employed on the return path is then obtained, each of the expressions requiring a plurality of input values that includes the above-noted parameters.
    Type: Application
    Filed: May 6, 2002
    Publication date: February 6, 2003
    Applicant: General Instrument Corporation
    Inventor: Robert Landis Howald
  • Publication number: 20030005467
    Abstract: A cable television (CATV) distribution system, and a method of forming and using the CATV distribution system. In a first embodiment, a narrowcast optical signal is generated by an uncooled laser and converted by a receiver into a narrowcast electrical signal. In a second embodiment, a narrowcast optical signal generated by an uncooled laser is combined with a broadcast optical signal by an optical coupler at a hub of the CATV distribution system to generate a composite optical signal, which at a CATV node is: split into the broadcast and narrowcast optical components, respectively converted into broadcast and narrowcast electrical components, and combined into a composite electrical signal. In a third embodiment, a narrowcast optical signal is generated by an uncooled laser and then combined with the broadcast optical signal by a single receiver.
    Type: Application
    Filed: June 29, 2001
    Publication date: January 2, 2003
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Marcel F.C. Schemmann, Venkatesh G. Mutalik
  • Patent number: 6490727
    Abstract: In hybrid fiber coaxial cable networks such as used in cable television where two-way digital communications are desired, a distributed termination system is provided. In such a system the home terminals are digital terminals, such as digital set-top boxes or cable modems using bi-directional transmission standards. The functionality of the head end controller in a conventional system is in this system distributed between the head end and the fiber nodes which link the coaxial cable and optical fiber portions of the system. Thereby the upstream detection takes place in the fiber nodes rather than in the head end by placing upstream burst receivers in the fiber nodes. Further there is a distributed method to enable this by providing synchronization and calibration control between the head end and the fiber nodes. Also, the return path is a digital return path supported by having the burst receivers located in the fiber nodes.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: December 3, 2002
    Assignee: Harmonic, Inc.
    Inventors: Moshe Nazarathy, Adi Bonen, Ilan Kepten, David Piehler
  • Patent number: 6462851
    Abstract: The present invention describes a method for transmitting reverse analog signals within a specific portion of a reverse band in an HFC communications system. Subscriber equipment (305) receives input defining the specific portion of the band for transmitting reverse analog signals. An optical transmitter (315) then converts the received reverse signals to digital reverse signals and transmits the digital reverse signals at a specified clock rate. Due to shifting of the digital reverse signals within the reverse bandwidth, shifting of the received digital signals reflect the specific bandwidth within which the reverse signals were originally transmitted.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: October 8, 2002
    Assignee: Scientific-Atlanta, Inc.
    Inventor: Lamar E. West, Jr.
  • Publication number: 20020144286
    Abstract: A method is presented comprising tuning a receiver of a broadband signal to a channel within the broadband signal to receive information including one or more cable modem operating parameters, and updating one or more operating parameters of the cable modem in accordance with the received information.
    Type: Application
    Filed: March 27, 2001
    Publication date: October 3, 2002
    Inventor: Shlomo Ovadia
  • Publication number: 20020144290
    Abstract: A method is presented comprising receiving a broadband signal at a receiver in accordance with a first modulation technique, tuning the receiver to a channel within the broadband signal, and modifying one or more operational parameters of the receiver to demodulate the channel in accordance with a second modulation technique to determine whether the channel is a data channel.
    Type: Application
    Filed: March 27, 2001
    Publication date: October 3, 2002
    Inventor: Shlomo Ovadia
  • Patent number: 6457178
    Abstract: A cable television system (100) includes ahead end section (105) for processing information provided from subscriber equipment via a reverse path within the system (100). The reverse signal is provided from subscriber equipment in the form of a broadband RF signal, which can include voice, data, and/or video information. The broadband RF signal is provided from a plurality of subscribers to a node (200) that pulse width modulates the RF signal to generate a reverse optical signal. The pulse width modulated optical signal is then provided to the head end section (105) for processing to recover the information contained therein.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: September 24, 2002
    Assignee: Scientific-Atlanta, Inc.
    Inventor: David H. Slim
  • Publication number: 20020129379
    Abstract: An optical signal return path system includes a transmitter having a sample clock generator for generating a sample clock and an RF signal receiver for receiving and converting an analog RF data signal into a first data stream of digitized RF data samples at a rate determined by the sample clock. Supplemental channel circuitry provides a second data stream. A multiplexor receives and combines the first data stream and second data stream, and an optical transmitter converting the combined data stream into a serialized optical data signal for transmission over an optical fiber. The second data stream may contain maintenance data reflecting an operational state of the transmitter. A receiver receives the optical data signal and recovers therefrom a digital data stream and an associated first clock having an associated first clock rate. The data stream is stored in a memory device at the first clock rate.
    Type: Application
    Filed: December 12, 2000
    Publication date: September 12, 2002
    Inventors: Frank H. Levinson, Gerald F. Sage, Arthur Michael Lawson, Willem A. Mostert
  • Publication number: 20020124265
    Abstract: A wavelength-division-multiplexer/demultiplexer 60 for separating an optical video signal 103 directed to a subscriber and an optical data signal 104 directed to the subscriber from an optical signal output from a center station 10, an E/O converter 51 of a video signal for converting an optical video signal 103 directed to the subscriber separated by the wavelength-division-multiplexer/ demultiplexer 60 into an electrical video signal, and an electrical signal distributor 52 for distributing an electrical signal received from the E/O converter 51 of the video signal to a plurality of subscribers' houses are provided. Hence, according to this invention, an optical component, which was provided in an equipment at each subscribers' houses 30a and 30b, becomes unnecessary.
    Type: Application
    Filed: September 26, 2001
    Publication date: September 5, 2002
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasutaka Kurauchi, Akira Takahashi, Shinya Makino
  • Publication number: 20020116719
    Abstract: A method for controlling a plurality of service units in a telecommunications system with a multi-carrier transmission scheme is provided. Specifically, in one embodiment, the method includes broadcasting control signals for the service units over a plurality of control channels distributed in a number of subbands of a frequency bandwidth. The method further includes identifying the service unit to use the control signal with an identifier.
    Type: Application
    Filed: January 11, 2002
    Publication date: August 22, 2002
    Applicant: ADC Telecommunications, Inc.
    Inventors: Mark J. Dapper, Michael J. Geile, Terrance J. Hill, Harold A. Roberts, Brian D. Anderson, Jeffrey Brede, Mark S. Wadman, Robert J. Kirscht, James J. Herrmann, Michael J. Fort, Steven P. Buska, Jeff Solum, Debra Lea Enfield, Darrell Berg, Thomas Smigelski, Thomas C. Tucker, Joe Hall, John M. Logajan, Somvay Boualouang, Heng Lou, Mark D. Elpers, Matt Downs, Tammy Ferris, Adam Opoczynski, David S. Russell, Calvin G. Nelson, Niranjan R. Samant, Joseph F. Chiappetta, Scott Sarnikowski
  • Publication number: 20020116721
    Abstract: A method for expanding customer bases for data services providers. The method includes connecting end-users of a plurality of services providers to a high-speed network dedicated to broadband data transport services. The end-users are connected to the respective headends of their services providers through a common data center of the high-speed network. The high-speed network is owned by a third party, that third party not being any of the services providers having end-users connected to the high-speed network.
    Type: Application
    Filed: February 16, 2001
    Publication date: August 22, 2002
    Applicant: GEMINI NETWORKS, INC.
    Inventors: Ronald Keith Dobes, Eugene Lee Lew, Leo Charles Cloutier
  • Patent number: 6433905
    Abstract: One or more pieces of equipment of a hybrid fiber-coaxial (HFC) network has a frequency agile transponder connected thereto. Each frequency agile transponder includes a transmitter (T) and a receiver (R) which are connectable to a coaxial line of the HFC network. Bidirectional communications can occur between a controller and each frequency agile transponder via the HFC network. The frequency agile transponder has analog inputs/outputs connectable to test points of the one or more pieces of equipment of the HFC network. The frequency agile transponder can test the test points and supply to the controller the results of the test. The transmit and receive center frequencies of the transmitter and receiver of the frequency agile transponder can be selectively and remotely adjusted by the controller to avoid signals at carrier frequencies utilized to transmit program material, data signals and/or telephony signals.
    Type: Grant
    Filed: May 18, 1999
    Date of Patent: August 13, 2002
    Assignee: Tollgrade Communications, Inc.
    Inventors: James N. Price, Jeffrey A. Gibala