Four-wire Switching Patents (Class 379/250)
  • Patent number: 9768950
    Abstract: Efficient codeword synchronization methods and systems for fiber channel protocol are disclosed. The method includes identifying a codeword boundary by detecting 100-bit known patterns in a bit codeword in a transmission.
    Type: Grant
    Filed: June 25, 2015
    Date of Patent: September 19, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Yang Fan Liu, Kai Yang, Jilei Yin, Zhao Qing Zheng
  • Patent number: 8818377
    Abstract: A radio terminal (10) includes an MIH user (14) configured to manage mobility from the first network to the second network; and an MIH function unit (13) configured to control a handover from the first network to the second network. The MIH user (14) notifies a link controller (12) via the MIH function unit (13) of a condition setting request including a first judgment logical formula being a condition to start an establishment of a radio link with the second network and a second judgment logical formula being a condition to execute a handover from the first network to the second network. The first judgment logical formula and the second judgment logical formula each indicate a combination of thresholds to be satisfied by a plurality of respective link is parameters in the radio link established with the first network.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: August 26, 2014
    Assignee: Kyocera Corporation
    Inventor: Tomoyoshi Yokota
  • Patent number: 8150019
    Abstract: A path redundant, hardware efficient communications interconnect (1) has embodiments that can present true any-to-any interconnect capability for first and second pathways (2) and (3) and can utilize double throw switches (25) with or without single throw switches (24) perhaps in staged collectives of sub arrays (4), (5), (6), (9), and (10). A loop-back communications interconnect (22) can be accomplished by an interleaved sub array (26). A quadrilateral center stage sub array (21) can be combined with asymmetric side stage sub arrays for hardware savings that are tenths of a percent of a traditional interconnect and even present eight fold savings over prior reduced hardware interconnects.
    Type: Grant
    Filed: August 8, 2008
    Date of Patent: April 3, 2012
    Inventor: Robert B. Smith
  • Publication number: 20040109554
    Abstract: Method and hardware for multiple distributing business or residential telephone connections and multiple Ethernet data connections over a standard 4 twisted pair telephone cable system.
    Type: Application
    Filed: August 25, 2003
    Publication date: June 10, 2004
    Inventor: Timothy Chris Mitchell
  • Patent number: 6728309
    Abstract: Disclosed is an architecture and method for high speed transmission over a four-wire subscriber line. Each modem in the present invention includes a V.90 transmit section and a V.90 receive section. The V.90 transmit section is dedicated to transmitting data over one pair of a four-wire subscriber line, while the V.90 receive section is dedicated to receiving data over the other pair of the four-wire subscriber line. The present invention permits full-duplex transmission at 56 Kbps over a four-wire subscriber line.
    Type: Grant
    Filed: January 14, 2000
    Date of Patent: April 27, 2004
    Assignee: 3Com Corporation
    Inventor: Earl Turner
  • Patent number: 5414763
    Abstract: A telephone switching apparatus includes a line network to which first and second telephones are connected and a hands-free trunk whose input and output terminals are connected to the line network. The line network is controlled such that voices from the first and second telephones are transmitted to the second and first telephones, respectively, through the hands-free trunk. A call transfer apparatus includes an outside-line interface to which first and second outside lines are connected and an adjusting unit for comparing the volumes of voices from the first and second outside lines and adjusting the volumes of the voices in accordance with the results of the comparison. The voices input from the first and second outside lines and adjusted in volume are transmitted to the second and first outside lines, respectively.
    Type: Grant
    Filed: February 25, 1992
    Date of Patent: May 9, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventor: Osamu Hirata
  • Patent number: 5325428
    Abstract: The communication carried out by an auxiliary terminal machine (AUX) utilizes audio signal wires picked up out of an 8-circuit and 6-contact switch (SW) or an 8-circuit and 3-contact switch (SW). An automatic switching circuit (SS), connected to the audio signal wires containing alternating current and separated from the audio signal wires with direct current, serves to detect the termination of the auxiliary terminal machine and switch back to the normal phone. The energy-saving exchanger supplying only alternating current is allowed to be connected to the auxiliary terminal machine for performing a communication function and then automatically switches back to the normal phone connection when the auxiliary terminal machine terminates the communication.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: June 28, 1994
    Inventors: Seizo Iwai, Tsuneko Iwai, Yukiko Iwai, Yumiko Iwai
  • Patent number: 5034978
    Abstract: The universal channel unit includes a channel interface circuit that uses a pair of fixed ratio transformers to terminate both two wire and four wire analog transmission facilities on a selectable basis. The universal channel unit also includes a plurality of signalling circuits, each of which is switchably connectable via the channel interface unit to provide a DC signalling interface to match the signalling format required by the associated analog transmission facility. The signalling circuits include: DX, FXO, FXS, and other DC signalling circuits. The AC component of the signals carried by the analog transmission facility is output to an adaptive impedance and balance circuit which functions to closely match the impedance of the analog transmission facility and minimize signal reflections under control of a microprocessor. This impedance and balance network is connected to a PCM interface that includes an adaptive echo canceller circuit as well as equalization and gain control circuits.
    Type: Grant
    Filed: December 15, 1989
    Date of Patent: July 23, 1991
    Assignee: XEL Communications, Inc.
    Inventors: Ninh T. Nguyen, John A. Neely, Terry D. Bolinger
  • Patent number: 5027347
    Abstract: The invention relates to an intercom system comprising a central unit and several remote stations connected by two-way lines to the central unit into a star network, whereby the lines are selectively interconnectable via the central unit for establishing a connection between desired remote stations. The number of simultaneous connections can be increased and the speech signals can be more reliably passed to the right remote stations when the two signal directions of each line are separated from each other at the central unit and the connection is established by connecting each signal direction separately.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: June 25, 1991
    Inventor: Heikki Malkki
  • Patent number: 4953055
    Abstract: A remote power-feeding and protection system for equipment connected by two transformers to a four-wire transmission link.The remote power-feeding and protection system and the remote power-feeding extractor protection device are intended for equipment connected by two transformers to a transmission link with two pairs of wires ensuring remote power-feeding of the fed equipment.Each transformer is connected to the two wires of one pair by two identical windings serially-connected between these two wires through a capacitor. The two pairs of wires constitute a phantom feed circuit, the two wires of a given pair being connected to the same terminal of a D.C. generator. The extraction and protection device comprises two rectifier bridges each separately connected by their inputs to a pair of wires and interconnected by their outputs in order to provide remote power feeding.
    Type: Grant
    Filed: September 9, 1988
    Date of Patent: August 28, 1990
    Assignee: Societe Anonyme dite : Telic Alcatel
    Inventors: Gerard Douhet, Yves Daviaud
  • Patent number: 4642425
    Abstract: An improved telephone paging system and method are disclosed. The sytem interfaces with a conventional telephone branching system, such as a PBX, and remote pager devices which are worn by subscribers to the system. A plurality of PBX extension telephone lines are connected to the system via a subscriber line interface, and one PBX extension line is connected to this system via a control line interface. The subscriber line interface is used to detect ring signals on the selected extension lines. When a ring signal has been detected on a selected line, the microprocessor-based system sends command signals to the PBX to place the incoming call on hold. The system identifies a paging code signal distinctively corresponding to the subscriber line on which the ring signal was detected. The identified paging code signal is sent to a transmitter which transmits the paging code signal to all pagers within its range.
    Type: Grant
    Filed: May 7, 1984
    Date of Patent: February 10, 1987
    Assignee: BBL Industries, Inc.
    Inventors: William H. Guinn, Jr., Richard M. Corbett, Robert S. Bundy, Jeffrey M. Seaman, Keith B. Duncan, Charles M. Link, II