Patents Examined by Benedict V. Safourek
  • Patent number: 6167063
    Abstract: Synchronizing wireless base stations by reception of a synchronization signal that is transmitted in an unused B channel of an ISDN link interconnecting a switching network and the base stations. The synchronization signals are generated by the tone circuit of the switching network which advantageously is a digital signalling processor (DSP). Each base station is interconnected to the switching network via two basic rate interface (BRI) links. Each base station can handle a maximum of three wireless handsets thus leaving one of the four B channels present in the two BRI links unused. It is this unused link that is utilized to transmit the synchronization signals from the switching network to the base stations. Furthermore, the switching network is configured in such a manner that all base stations receive the synchronization signals at the same time over the unused B channels.
    Type: Grant
    Filed: December 8, 1995
    Date of Patent: December 26, 2000
    Assignee: AT&T Corp
    Inventor: Michael Ray Ross
  • Patent number: 6097707
    Abstract: A single channel wireless digital communication network [10] has a cellular topology which includes a central unit [12] ("CW") controlling communications with a plurality of remote units [14] ("TU") in a star configuration. Network access is synchronously controlled through a time division multiplexed cycle [20] of variable total duration having an up-link phase [21] of a variable number of fixed size time slots [25, 27, 27a], each pre-assigned by reservation by a remote unit, and a down-link phase [22] of a variable number of variable size slots [31a, 31b] which are adaptively utilized. The CU adaptively manages all slot assignments according to a variety of parameters. RU up-link slot reservations are confirmed by the CU in a variety of ways. During the up-link phase, RU's which did not reserve a slot on the previous up-link cycle are temporarily suspended and are then polled or periodically tested for re-entry.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: August 1, 2000
    Inventors: Migdat I. Hodzic, James M. Brennan
  • Patent number: 5959980
    Abstract: A system and method for time division duplex communication over a single frequency band wherein guard time overhead is reduced by active adjustment of reverse link transmission timing as a function of round trip propagation time. A time frame is divided into a plurality of time slots, during each of which the base station transmits to a user station and the user station transmits to the base station. Communication is initiated by a round trip timing transaction. In response to a general polling message from the base station, a user station seeking to establish communication transmits a short reply message. The base station calculates the distance of the user station by measuring the propagation delay with respect to receipt of the reply message. The base station sends a timing adjustment command to the user station instructing the user station to advance or retard its timing according to the calculated distance, so as to minimize guard times between time slots.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: September 28, 1999
    Assignee: Omnipoint Corporation
    Inventor: Logan Scott
  • Patent number: 5898695
    Abstract: An apparatus for filtering TS packets multiplexed with a plurality of programs and sending the filtered packets to decoders. A packet landing buffer is provided in a RAM used for a microprocessor for system control. After a channel is selected, the microprocessor filters video and audio data and performs a value added service process.
    Type: Grant
    Filed: March 27, 1996
    Date of Patent: April 27, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Fujii, Masuo Oku
  • Patent number: 5872788
    Abstract: A system is disclosed for the transmission of data between a central unit and at least one functional unit via lines where each functional unit is connected to at least one sensor or actuator. Each functional unit includes an output amplifier for the transmission of data to a further functional unit and a memory for the storage of an interchangeable address. The system has three different operating modes which make it possible, depending on the requirement, to address the functional units as desired, to carry out a data interchange, or only to receive data.
    Type: Grant
    Filed: September 5, 1995
    Date of Patent: February 16, 1999
    Assignee: Zellweger Luwa AG
    Inventors: Jurg Kreis, Johannes Heusser
  • Patent number: 5872780
    Abstract: An internal signal within a SONET element has a transport format having overhead and payload mapped in a manner similar to the Synchronous Optical Network standard mapping, except having selected overhead bytes defined differently, including a byte used for communicating odd parity calculated over an odd number of bytes of a frame of the transport format to determine correct or incorrect parity, selected bytes used for inter-module automatic protection switching, and a pointer having a selected fixed value, along with an adjusted virtual tributary pointer in a virtual tributary mode.
    Type: Grant
    Filed: May 21, 1992
    Date of Patent: February 16, 1999
    Assignee: Alcatel Network Systems, Inc.
    Inventors: Sahabettin C. Demiray, Dale L. Krisher, William B. Weeber
  • Patent number: 5870378
    Abstract: A Multi-Code (MC) Code Division Multiple Access (CDMA) receiver receives N (where N.gtoreq.1) encoded signal channels over multiple air signal paths. The N signal channels are encoded using a properly chosen subset of Walsh codes based on a Walsh-Matrix, W.sup.M, where M is a power of two. In the disclosed MC-CDMA receiver, a timing correlator means recovers the timing and control signal for the N signal channels received over any particular signal path; a FWHT circuit together with a second correlator means decodes all of the N signal channels.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: February 9, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Howard C. Huang, Chih-Lin I, Stephan ten Brink, Charles Albert Webb, III
  • Patent number: 5870393
    Abstract: In a spread spectrum communication system, one (W.sub.n) of a series of orthogonal codes for spectrum spreading is assigned to signal-to-noise ratio measurement in a terminal. On the basis of a noise signal detected by de-spreading a signal received from an antenna with the above described orthogonal code W.sub.n and a pilot signal, each terminal derives a signal-to-noise ratio. Each terminal transmits the signal-to-noise ratio to the base station as a power control signal. On the basis of signal-to-noise information received from each terminal as the power control signal, the base station controls signal transmission power for each terminal.
    Type: Grant
    Filed: July 11, 1996
    Date of Patent: February 9, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Yano, Nobukazu Doi
  • Patent number: 5867493
    Abstract: A telecommunications apparatus is disclosed for use in conjunction with a local switch. The apparatus operates in a bypass mode for messages that do not require compression/decompression, and in a pass-through mode for those which do. A selective compressor/decompressor is provided to decompress incoming information for which the local switch is to operate in pass through mode and to compress outgoing information for which the local switch has operated in pass through mode. A selective masker/demasker is operative to expand information to be bypassed by the switch without decompressing the information from a compressed form to an expanded form and to restore information bypassed by the switch from the expanded form to the compressed form.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: February 2, 1999
    Assignee: Rad Data Communications Ltd.
    Inventor: Yehuda Zisapel
  • Patent number: 5864555
    Abstract: Methods and apparatus are provided for handling asynchronous transfer mode (ATM) cells sent from first user equipment through a plurality of ATM nodes and destined for second equipment, when the second equipment does not support ATM operations and maintenance (OAM) functionality. In particular, an ATM node connected to the second equipment is configured as an OAM proxy connection end-point for the second equipment such that ATM data cells which are destined for the second equipment are sent in a usual fashion, but ATM OAM cells destined for the second equipment are terminated and acted upon by the ATM node and are not forwarded to the second equipment. The proxy connection end-point functionality is preferably obtained by providing a user-friendly management information database (MIB) which stores configuration information for the ATM node.
    Type: Grant
    Filed: July 5, 1996
    Date of Patent: January 26, 1999
    Assignee: General DataComm, Inc.
    Inventors: Deepak Mathur, David X. Chen, L. David Danenberg
  • Patent number: 5859850
    Abstract: A method and apparatus for interfacing ATM network packet type communications to STM frame type communications. This method and apparatus is especially useful for interfacing isochronous ATM cells to STM frames. The apparatus concerns an elastic store which receives ATM cells and sorts them in a set of FIFOs into their respective frames. The FIFO storing and retrieval method removes jitter and delay. A controlled clock within the elastic store clocks reads the information out of the FIFOs and into a STM network.
    Type: Grant
    Filed: December 28, 1995
    Date of Patent: January 12, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Robert Leroy Lien
  • Patent number: 5841770
    Abstract: One or more interrogating commander stations and an unknown plurality of responding responder stations coordinate use of a common communication medium. Each commander station and each responder station is equipped to broadcast messages and to check for error in received messages. When more than one station attempts to broadcast simultaneously, an erroneous message is received and communication is interrupted. To establish uninterrupted communication, a commander station broadcasts a command causing each responder station of a potentially large first number of responder stations to each select a random number from a known range and retain it as its arbitration number. After receipt of such a command, each addressed responder station transmits a response message containing its arbitration number. Zero, one, or several responses may occur simultaneously.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: November 24, 1998
    Assignee: Micron Technology, Inc.
    Inventors: Charles K. Snodgrass, David H. Allen, John R. Tuttle, Robert R. Rotzoll, George E. Pax
  • Patent number: 5838679
    Abstract: The present invention relates to an Asynchronous Transfer Mode (ATM) multi-channel switch with a structure of grouping/trap/routing that, by designating a port as a group, could accept not only the services having higher speed than the speed of input ports, but also the services having super-rate speed by comprising: an input processing unit for executing reading control of externally inputted cells and adjusting synchronization between an externally inputted cell and a cell returned by blocking and feedback; a channel grouping unit for grouping cells outputted from the input processing unit, according to switching control data; a trapping unit for deciding whether cells grouped in the channel grouping means require switching beyond the capacity of the pertinent channel and, if these cells require switching beyond the capacity of the channel, sending them to the input processing unit by feedback; and a routing unit for routing cells outputted from the trapping unit.
    Type: Grant
    Filed: July 6, 1995
    Date of Patent: November 17, 1998
    Assignees: Electronics and Telecommunications Research Institute, Korea Telecommunication Authority
    Inventors: Hyup Jong Kim, Kyeong Soo Kim, Chan Pak
  • Patent number: 5838673
    Abstract: A system for minimizing co-channel interference between transmission sectors at their common periphery. The system exploits the geographic separation of potentially interfering mobile transmitters and utilizes transmission power control. The system employs sectored antennas in a combined frequency hopping, TDMA system wherein each subscriber in a particular sector is assigned a time slot in the system based upon that subscriber's geographic location within that sector. The transmission power in the sector is reduced during certain predetermined time slots and subscribers who are remote from the fringe of the sector are assigned to these power reduced time slots. During up-link the transmission power for subscribers located proximal to the fringe are reduced to cause less co-channel interference between their signals and the signals from other subscribers in different sectors having the same time slot.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: November 17, 1998
    Assignee: Geotek Industries, Inc.
    Inventors: Mordechai Ritz, Giora Silbershatz, Shmuel Miller
  • Patent number: 5835485
    Abstract: To set-up a dispatch call, a controller identifies the destination units, destination sites, controlled devices and paths needed to support the call, and which LAN bridges will be used to create the communication paths. The controller then assigns the controlled devices a temporary address identical to the permanent address of one of the controlled devices, and then informs the LAN bridges which LAN ports should carry messages containing the temporary address. With all controlled devices having the same temporary address, and with the LAN bridges ready to pass messages containing the temporary address along a chosen path, the controlled device assigned to support the call request can transmit the messages generated by a source communication unit to other controlled devices using the temporary address. Thus, only one representation of a message produced by the source communication unit is transmitted from the assigned controlled device.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: November 10, 1998
    Assignee: Motorola, Inc.
    Inventors: Gary W. Grube, Michael D. Sasuta, Robert William Furtaw
  • Patent number: 5828650
    Abstract: The invention relates to the organization of phase references in a data transfer system based upon the multiplexing of orthogonal frequency components, when transmissions in the system are composed of relatively short symbol sequences. In accordance with the invention, in the first symbol (OS1) of the sequence differential phase-shift keying between elementary signals is carried out, based upon a phase reference (Ref) transmitted in one or several subfrequency bands (fc) and upon a phase shift chain propagated one subfrequency thereof at a time. In each subfrequency band in the subsequent symbols of the sequence phase-shift modulation refers to the elementary signal of the preceding symbol of the same subfrequency band. The invention may be applied with benefit to digital cellular network systems which employ the OFDM method.
    Type: Grant
    Filed: July 2, 1996
    Date of Patent: October 27, 1998
    Assignee: Nokia Mobile Phones Ltd.
    Inventors: Esa Malkamaki, Jari Junell
  • Patent number: 5825775
    Abstract: A method and apparatus for generating a display containing information about both the local and remote traffic handled by an integrated router/hub is provided. An integrated router/hub routes local messages between devices on a first local area network, and routes remote messages between the first local area network and a second local area network. The integrated router/hub stores a first set of values related to the local messages, and a second set of values related to the remote messages. A network management station executes a network management application the includes instructions which cause the network management station to generate a display of the information stored in the integrated router/hub. In response to user input, the network management station requests the information from the integrated router/hub, receives the information from the integrated router/hub, and generates the display of the information. The display may include charts that illustrate statistics derived from the information.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: October 20, 1998
    Assignee: Bay Networks, Inc.
    Inventors: Jeffrey A. Chin, Leon Y.K. Leong, Frank S. Lee
  • Patent number: 5825774
    Abstract: A method and apparatus for increasing the throughput of a communications internetworking device. The method involves the generating, by internetworking device hardware, of a predetermined code vector in response to the current state of the communications internetworking device and information contained in a data packet received by the internetworking device. In response to the hardware generated predetermined code vector, a predetermined software routine is executed by a microprocessor in the internetworking device which controls how the data packet is to be transmitted to its destination. By using hardware to generate the code vector, time is saved over having software determine how the internetworking device is to handle the data packet.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: October 20, 1998
    Assignee: 3Com Corporation
    Inventors: David C. Ready, Stephen L. Van Seters, John A. Flanders
  • Patent number: 5822309
    Abstract: The present invention is a signaling and control architecture for establishing a connection between mobile users in a wireless ATM LAN. The ATM LAN includes a plurality of portable base station (PBS) switching nodes coupled together to enable communication between said nodes, wherein the nodes are configurable in an arbitrary topology to form an ad-hoc network. The present invention includes network management techniques for configuration of data tables used for connection control. Mobility management techniques are disclosed to handle mobile sign-ons and idle handoffs, locate mobile users during connection and setup and perform handoffs when a mobile is actively involved in a connection. Connection control procedures are also included for setting up and releasing connections on demand.
    Type: Grant
    Filed: June 15, 1995
    Date of Patent: October 13, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Ender Ayanoglu, Kai Yin Eng, Mark John Karol, Pramod Pancha, Clark Woodworth, Malathi Veeraraghavan
  • Patent number: 5822313
    Abstract: A technique is disclosed for allowing a seamless handover between base stations in a TDMA controller as a telephone handset is transported from one base station's area to another. The disclosed circuitry enables the TDMA controller to assess the quality of the handover before switching to the new base station. When it is determined that a handover operation is to commence, transmissions are made in the original slot time and a handover slot time within the same frame. Also during the same frame, data is received at two separate slot times. Only when it is determined that the data received in the handover slot time contains no transmission errors is the handover completed by then only transmitting on the handover slot transmit time and receiving on the handover slot receive time. In the preferred embodiment, it is determined whether the received data contains no transmission errors by detecting the CRC codes, the signal strength, and the existence of any invalid words.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: October 13, 1998
    Assignee: National Semiconductor Corporation
    Inventors: Charles J. Malek, David L. Weigand, Dennis M. Rose, Gerard G. Socci