Patents Examined by Tuan Q Ho
  • Patent number: 6137788
    Abstract: A CDMA demodulating apparatus with an improved interference canceling effect when there are a large number of communicators. A reception signal having a frame configuration in which a pilot signal of a known pattern is inserted between information signals is received from a plurality of communicators. Transmission data of each communicator is demodulated, an interference canceler for estimating is provided in a plurality of stages, in each channel of each stage, a variation of transmission path is estimated in each path to achieve data demodulation and estimation of interference replica. The later the stage, the more error of interference signal replica can be reduced, thereby improving the interference canceling effect. An even better effect can be obtained when interference canceling is performed after detecting a reception level of each channel by summation of reception power of each path of each channel, and channel ranking is determined in the order of higher reception level.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: October 24, 2000
    Assignee: NTT Mobile Communications Network, Inc.
    Inventors: Mamoru Sawahashi, Hidehiro Andou, Yoshinori Miki, Kenichi Higuchi
  • Patent number: 6108351
    Abstract: The process is characterized in that the pilot signals (10) generated upstream of the device (11) whose non-linearity it is desired to measure pass through a known non-linear device (15) delivering intermodulation products of known characteristics and in that at least one of the known intermodulation products is harnessed in order to modulate, with the aid of synchronous detection circuits (17), at least one of the signals relating to the components of the intermodulation products of the device to be measured.The applications pertain to the analog transmission of television signals over optical fibers.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 22, 2000
    Assignee: Thomson Broadcast Systems
    Inventors: Patrick Hardy, Stephane Hergault
  • Patent number: 6072791
    Abstract: A spread spectrum portable telephone apparatus operates with long wait times and with little battery depletion while waiting. A mobile unit receiver receives and detects radio signals, analog-to-digital (AD) converts the detected reception signals, waveform-shapes the converted signals, despreads and decodes the waveform-shaped signals with a spread signal, frame-resolves the decoded signals, and extracts reception date from the frame-resolved signals. A data receiver is included which has, for both a pager channel and a communications channel, a narrow band AD converter circuit, a narrow band reception filter for waveform-shaping the AD converted signals, and a correlator which despreads and decodes the waveform-shaped signal using a spread code generated by a low speed spread code generator circuit. When waiting, calls to the apparatus are waited for with the power turned on only to the paging channel data receiver.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: June 6, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Taku Nagase, Osamu Kato, Gen-Ichiro Ota
  • Patent number: 6049547
    Abstract: An arrangement for lookahead interflowing traffic among a plurality of serving sites of one customer. Incoming calls received at a site are queued if they cannot be served immediately. Queued calls are then examined periodically and if the call has not yet been served by a local agent and if the call is one of the oldest call in the queue, then the call is a candidate for lookahead interflow. A candidate for lookahead interflow causes a message to be sent to another switch requesting that the call be interflowed. If the other switch accepts the call, the call is routed to that other switch; if the other switch does not accept the interflowed call then the call remains in the queue of the requesting switch and is reexamined at the next period. All calls in the queue are completed to a local agent if a local agent is available.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: April 11, 2000
    Assignee: Lucent Technologies Inc.
    Inventors: Thomas S. Fisher, Andrew Derek Flockhart, Sujeanne Foster, Raechel Greschler, Eugene P. Mathews, Robert Daniel Nalbone
  • Patent number: 6049534
    Abstract: A communication system includes a control unit, a switch and a diversity hand-over processing unit connected to the control unit and the switch for receiving, both a first communication signal received from a radio base station which outputs the hand-over instruction, and a second communication signal which receives it from another radio base station to which the communication signal will be hand-over to output one of the first and second communication signals to the associated interface circuit, and for transmitting the communication signal received through the radio base station from the mobile station on the reception side for communication to both the interface circuit associated with the radio base station as a source of hand-over and the interface circuit associated with the radio base station as a destination of hand-over.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: April 11, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Kenichi Sakamoto, Tsutomu Kusaki, Masaru Murakami, Takashi Yokoyama
  • Patent number: 6049523
    Abstract: The delineation and quick invocation of protection switching is achieved by generating a protection indicator having an initial state at the point that a transmission facility failure is detected and passing the indicator downstream. A switch that receives the indicator either increments or decrements the indicator in accordance with predetermined rules. However, a switch that receives the indicator when it reaches an active state immediately invokes protection switching if that switch is at the sink end of an associated protection path.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: April 11, 2000
    Assignee: Lucent Technologies Inc.
    Inventors: Jon Anderson, James S. Manchester, Maarten Petrus Joseph Vissers
  • Patent number: 6041049
    Abstract: A method enables each node in a multi-nodal network to construct a routing table to all other nodes in the network. Each "home" or originating node performs a method which includes the steps of: transmitting a query to all immediate neighbor nodes and recording in a routing table, responses received which identify the neighbor node at the terminus of each link; transferring to each neighbor node, home node routing table entries and receiving routing table entries from each neighbor node; and, for each routing table entry to a node that is received from a neighbor node, if the route indicator is already present in the home node routing table, ignoring the entry; if the new entry indicates a route to a new node, entering the new node and a route identifier; and if the entry indicates a route to a node for which there is already an entry in the home node routing table, noting the new entry as a lower priority route to the node.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: March 21, 2000
    Assignee: International Business Machines Corporation
    Inventor: James T. Brady
  • Patent number: 6034944
    Abstract: A communication system capable of reliably recovering its communication functions on its own when a fault occurs, and which can be used to construct a highly flexible network. This communication system is configured so that a plurality of node devices (12) supporting data generating sources are connected via communication paths (13) that use ATM technology to a plurality of center devices (11), just as if it possessed distributed ATM switch functions. When the communication paths (13) between two (2) node devices (12-2 and 12-3) are cut, the center device (11-2) detects the fault point, and autonomously recovers communication functions by transferring the node device (12-2) originally under its control to the control of the center device (11-1). When this happens, the center device 11-2) cannot communicate via the communication paths (13) due to the fault, and must use a local communication means such as a wide area network (16) to communicate with the center device (11-1).
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: March 7, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yutaka Seki, Keiichi Obara, Tomoo Kunikyou, Hidekazu Turuta, Hirotaka Sakajiri
  • Patent number: 6031825
    Abstract: A system for providing an IR-link between a mobile phone and its accessories to transmit audio, control, and data signals between them in an apparent full-duplex real time mode using a conventional half-duplex IR-transceiver with suitable FIFO registers and control means. The "direction" of the half-duplex channel is "switched" by the system which may be embodied in an IR-link module, having transmission channels for digital full-duplex audio signals, slow data messages and fast data messages, and for some control data. The module is connected to the baseband of a phone through a baseband interface (BBIF) and communicates through a media interface (MIF) and an infrared interface (IRIF) with free air space or a lightguide. A link-specific low-level protocol is used for audio and slow data message transmission but the link hardware of the module may also support other protocol implementations. The system may be implemented in hardware and/or software.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: February 29, 2000
    Assignee: Nokia Mobile Phones Limited
    Inventors: Terho Kaikuranta, Markku Lipponen, Seppo Jarvensivu, Toni Sulavuori
  • Patent number: 6031837
    Abstract: A method for establishing bidirectional connections and multiple connections performed by an ATM switching device is disclosed, and the method may include the steps of recognizing a connection request message sent from one calling subscriber, including information concerning other n-1 called subscribers in the asynchronous transfer mode switching device transmitting the connection request message to the n-1 called subscribers, and transmitting a response to the calling subscriber from the n-1 called subscribers from the asynchronous transfer mode switching device; and establishing bidirectional connections between the calling subscriber and the called subscribers.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: February 29, 2000
    Assignee: Fujitsu Limited
    Inventor: Fumio Hirase
  • Patent number: 6028857
    Abstract: A self-organizing wireless network includes a plurality of nodes, each of which is configured to originate messages, be a destination of messages and relay messages. Each message is transmitted in a frame that includes the cost of conveying the message to the destination node for the message and also the cost so far expended in the conveying of the message. Each time the message frame is transmitted, either by the originating node or by a relaying node, the node ascertains whether the cost to convey the message from that node to the destination node is less than the conveying cost contained in the received frame. If it is, the node retransmits the frame after having incremented the incurred cost by the relay cost of that node and decremented the cost to convey by the same value. Otherwise the node discards the message.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: February 22, 2000
    Assignee: Massachusetts Institute of Technology
    Inventor: Robert D. Poor
  • Patent number: 6021129
    Abstract: A modem operable to communicate information from a communications link to a host using a universal serial bus includes a modem memory operable to store a plurality of ATM cells. The modem also includes a receive manager operable to receive a plurality of ATM cells from the communications link and to store the ATM cell in the modem memory. The receive manager further operates to format the ATM cells into universal serial bus packets, and to transmit each universal serial bus packet to the host as soon as the packet is full. The modem further includes a short packet instigator operable to determine whether each ATM cell contains a termination condition associated with the content of the ATM cell, and in response to determining that an ATM cell contains a termination condition, to instigate transmission of a short packet comprising a universal serial bus packet carrying less than its capacity.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: February 1, 2000
    Assignee: Efficient Networks, Inc.
    Inventors: Kimberly I. Martin, Kenneth A. Lauffenburger, Klaus S. Fosmark, William A. Perry, Jr.
  • Patent number: 5995496
    Abstract: In packet switched data transfer of the cellular radio system, the control of the transmission power comprises characteristics as well of the closed-loop control and the open-loop control. Before forming the connection and during long pauses between the packets, the terminal device measures the control signal transmitted by the base station and compares its signal power (R0) to the target level (t0), that is included by the base station in the control signal as a parameter. The base station informs in the control signal also the transmission power, whereby the terminal device sets the same power to be its transmission power, corrected by the difference between the target level and the measured quality of the link (t0-R0). In addition, also the measured quality of the link (RXQUAL) is transmitted in the acknowledgment messages of the packets, whereby the transmitting device changes its transmission power so that the quality will be controlled to the certain target level.
    Type: Grant
    Filed: June 16, 1997
    Date of Patent: November 30, 1999
    Assignee: Nokia Mobile Phones Limited
    Inventors: Zhichun Honkasalo, Jari Hamalainen, Harri Jokinen, Richard Fehlmann