Patents Represented by Attorney Eugene S. Indyk
  • Patent number: 5498863
    Abstract: An optoelectronic detector includes multilayered semiconductor structures that are placed at particular positions in a standing wave pattern in order to measure the intensity of the light beams passing through said structures' layers. The detector is made sensitive to particular wavelengths by either changing the light beams intensity or varying the absorbance of the layers.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: March 12, 1996
    Assignee: AT&T Corp.
    Inventor: David A. B. Miller
  • Patent number: 5490199
    Abstract: Non-intrusive monitoring and analysis of real-time facsimile transmissions is accomplished. Analog impairment measurements are made on the high speed page signal in those transmissions and protocol analysis is made on the low speed control messages in those transmissions. These measurements and analysis are a powerful tool for trouble shooting service problems afflicting facsimile transmissions. Real customer traffic can be monitored to detect circuit impairments and to evaluate service being provided. A selected incoming trunk of a central office switch is accessed and a monitoring function with respect to that trunk is established. A signal classification operation is performed, which identifies the presence of a facsimile transmission and what kind of facsimile transmission it is.
    Type: Grant
    Filed: February 21, 1992
    Date of Patent: February 6, 1996
    Assignee: AT&T Corp.
    Inventors: Richard C. Fuller, Thomas W. Goeddel, R. B. Heick, Martin Herzlinger, Subramanian Krishnamurthy
  • Patent number: 5477164
    Abstract: An adiabatic dynamic non-inverter circuit is a mechanism by which a logic level signal and its inverse are simultaneously available in dynamic logic circuitry without significant power dissipation. The principles of this non-inverter circuit are used to create an exclusive-or gate which also does not dissipate significant power. Both of these circuits employ simplified circuit topologies.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: December 19, 1995
    Assignee: AT&T Corp.
    Inventor: John S. Denker
  • Patent number: 5477197
    Abstract: An undesirable relationship between user applied input frequency control voltage and output frequency of a voltage controlled oscillator is counteracted by controlling the characteristics of an amplifier stage in the oscillator as a function of frequency control signal in addition to controlling the output frequency of the oscillator as a function of the capacitance of a user controlled variable capacitance in response to the frequency control signal.
    Type: Grant
    Filed: October 24, 1994
    Date of Patent: December 19, 1995
    Assignee: AT&T Corp.
    Inventor: Shawn M. Logan
  • Patent number: 5473270
    Abstract: Power dissipation in precharge paths used in adiabatic dynamic logic circuitry is reduced by a precharge boost circuit which decreases the impedance between a clock node and an output node in such logic circuitry and thereby increases the charging current from a clock signal generator. In one example, a diode used to precharge an output node in adiabatic dynamic logic circuitry is selectively shorted by a controllable switch selectively connected in parallel with the diode when the output node is to be precharged.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: December 5, 1995
    Assignee: AT&T Corp.
    Inventor: John S. Denker
  • Patent number: 5473269
    Abstract: A novel family of adiabatic dynamic logic gates can have power*delay products at least an order of magnitude or more below that which was possible in previous families of logic gates. No complex circuitry or unusually configured devices are needed to implement this logic family. In particular, this logic family requires fewer devices and less area per logic gate as compared with ordinary CMOS logic circuitry. This is unlike previous reversible logic proposals which required large numbers of transistors per gate. This logic circuitry can operate from very low supply voltages and need not be optimized for a particular voltage. This logic does not suffer from crowbar currents usually found in prior circuitry such as CMOS logic. Logic levels are regenerated at nearly every stage unlike some previous schemes which reduce energy dissipation only by sacrificing logic levels.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: December 5, 1995
    Assignee: AT&T Corp.
    Inventor: Alexander G. Dickinson
  • Patent number: 5471318
    Abstract: A circuit configuration in a multimedia network representing a controllably persistent virtual meeting room simulates an actual meeting room where conferences between two or more people may be held. This facilitates the creation in the network of flexible, long-term multimedia conferences between conferees who are separated from one another. Any number of conferees may communicate with one another via one or more of audio, video, and data. Virtual meeting rooms may persist in the network for predetermined periods of time controlled by the users of the meeting room. The room may remain in the network independent of whether or not a user is connected to the room. The meeting room is a vehicle whereby the activity of various media servers is coordinated to effectuate conferences between multiple participants in more than one medium. The servers are associated with storage devices which may record or store certain aspects of multimedia conferences using the virtual meeting room.
    Type: Grant
    Filed: April 22, 1993
    Date of Patent: November 28, 1995
    Assignee: AT&T Corp.
    Inventors: Sudhir R. Ahuja, Murali Aravamudan, James R. Ensor
  • Patent number: 5463620
    Abstract: A wide variety of call traffic is effectively integrated in a single broadband communications network. Calls having widely differing bandwidth requirements and sensitivities to delay are handled by the network with efficient, effective, and fair bandwidth allocation and transmission scheduling. This is accomplished by classifying each call in accordance with certain signal characteristics, such as required bandwidth and sensitivity to delay. Each call class is directed to a separate queuing circuit. Some calls in certain classes, such as those associated with high-bandwidth constant bit rate services, are each directed to their own individual queuing circuits. Other calls within a class are statistically multiplexed into a single queuing circuit for that class.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: October 31, 1995
    Assignee: AT&T IPM Corp.
    Inventor: Kotikalapudi Sriram
  • Patent number: 5463685
    Abstract: An outbound call management capability is provided for a public switched telephone network by a network based outbound call management (NOCM) complex, which can be accessed by all subscribers to the public switched network through one or more central offices in the network. A predetermined list of telephone numbers is stored in a data base in the NOCM complex for each subscriber who uses the NOCM services. The telephone numbers are automatically dialed at one or more predetermined scheduled times. When one of the dialed telephones is answered, the NOCM complex sets up a connection through the public switched telephone network between the called party and one or more attendants at one or more telephone numbers specified by a customer of the NOCM services.
    Type: Grant
    Filed: November 9, 1994
    Date of Patent: October 31, 1995
    Assignee: AT&T IPM Corp.
    Inventors: Barbara I. Gaechter, Paramdeep S. Sahni, I. Grace Tseng
  • Patent number: 5459722
    Abstract: A plurality of ATM networks may be interconnected to allow communication of voice-band signals between them by using one or more PSTNs and a novel interface that converts ATM formatted data packets to a format usable by digital multiplication equipment (DCME). Such an interface thus allows the DCME to advantageously function as a gateway between the ATM network and PSTN by providing for optimum bandwidth usage between the networks. In an illustrative example of the invention, a DCME available from AT&T as the Integrated Access and Cross Connect System ("IACS"), is provided with an ATM-to-DCME interface that converts ATM formatted packets to a regular channelized bitstream usable as an input by the IACS. The interface and the IACS are positioned on both ends of a PSTN to allow for connectivity between the PSTN and a plurality of ATM networks, as well as the required optimization of bandwidth usage.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: October 17, 1995
    Assignee: AT&T Ipm Corp.
    Inventor: Mostafa H. Sherif
  • Patent number: 5459414
    Abstract: A novel family of adiabatic dynamic logic gates can have power*delay products at least an order of magnitude or more below that which was possible in previous families of logic gates. No complex circuitry or unusually configured devices are needed to implement this logic family. In particular, this logic family requires fewer devices and less area per logic gate as compared with ordinary CMOS logic circuitry. This is unlike previous reversible logic proposals which required large numbers of transistors per gate. This logic circuitry can operate from very low supply voltages and need not be optimized for a particular voltage. This logic does not suffer from crowbar currents usually found in prior circuitry such as CMOS logic. Logic levels are regenerated at nearly every stage unlike some previous schemes which reduce energy dissipation only by sacrificing logic levels.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: October 17, 1995
    Assignee: AT&T Corp.
    Inventor: Alexander G. Dickinson
  • Patent number: 5455701
    Abstract: A high-speed, high-capacity, asynchronous transfer mode packet switching system comprises electronic and optical components. The switching system may be a high-capacity multiple-gigabit-per-second optical system controlled by a relatively low-speed electronic controller operating at one hundred megabit-per-second rates. The switching system comprises a plurality of N input lines. Each of the N lines carries a succession of data packets or cells to the switching system. Each of the cells is input to the switch in time slots or cell periods of predetermined duration. A laser transmitter producing a separate and distinct carrier frequency identifying its associated input is responsive to each of the N input lines. The laser transmitters are connected to the input of an optical star coupler which is connected to a series of tunable receivers. There is one tunable receiver for each output of the switching system.
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: October 3, 1995
    Assignee: AT&T Corp.
    Inventors: Kai Y. Eng, Mark J. Karol
  • Patent number: 5450511
    Abstract: The efficiency and freedom from cross-talk achieved by transmissive multiplexer/demultiplexer devices is achieved in a reflective multiplexer/demultiplexer device. The reflective geometry avoids the large size devices necessitated by transmissive geometries handling a large number of optical channels. The reflective geometry also avoids long bends in waveguides used in optical gratings in high efficiency transmissive geometries. Integrated optical multiplexers/demultiplexers in accordance with this invention comprise a plurality of waveguides for carrying unmultiplexed optical signals interleaved with a plurality of waveguides for carrying multiplexed optical signals. The two pluralities of waveguides are connected to the boundary of a free space region. The pluralities of waveguides communicate through the free space region with an optical grating comprising a plurality of waveguides each terminated in a reflective element.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: September 12, 1995
    Assignee: AT&T Corp.
    Inventor: Corrado Dragone
  • Patent number: 5392343
    Abstract: Easily accessed and widely available language interpretation services are provided in a public switched telephone network by a common platform adjunct which automatically connects an interpretation services subscriber with a selected language interpreter associated with a language interpretation platform in the network. A subscriber dials, for example, an international telephone number which includes a code indicating that the call is an international call, a country code, a city code, and a local destination number. The ANI of the subscriber is detected and the call is routed to the adjunct which further verifies and validates the subscriber. The adjunct places a call through the public switched telephone network to the language interpretation platform. The call is answered either by an automatically preselected interpreter or by a human operator who causes the call to be manually transferred to a desired interpreter.
    Type: Grant
    Filed: November 10, 1992
    Date of Patent: February 21, 1995
    Assignee: AT&T Corp.
    Inventors: Michael Davitt, Alan N. Dunn, Paula M. Goldstein, Edgar J. Grijalva, Michael Neal, Christine P. Peterson, Christos I. Vaios
  • Patent number: 5384826
    Abstract: A cellular switching system and architecture is described in which the switching associated with a call originated within one cell but now serviced within another cell is distributed among base stations which are interconnected with each other through a local area network or a packet switch. The routing procedure associated with the point of origin for a given call is stored in the memory of a switch of public switched telephone network. As an active subscriber crosses a cell boundary, the switch routes all packets of information for the given call to the originating base station for the duration of the call. Importantly, each base station then forwards each packet to the subscriber's current base station via the local area network or a packet switch.
    Type: Grant
    Filed: July 28, 1993
    Date of Patent: January 24, 1995
    Assignee: AT&T Bell Laboratories
    Inventor: Noach Amitay
  • Patent number: 5373516
    Abstract: A monolithically integrated wideband laser which is rapidly tunable over a wide optical frequency range comprises two series connected frequency routers of different resolutions formed in a semiconductive wafer defining a tuned cavity. A control circuit applies electrical energy to predetermined controllably transmissive waveguides connecting the frequency routing devices with reflective elements defined in the wafer. This tunes the laser to a desired one of a plurality of optical frequencies. Application of such electrical energy creates frequency selective pathways through the wafer able to support up to hundreds of selected lasing frequencies across the entire bandwidth of a semiconductive medium. This laser is economical to construct and is useful in high capacity, high speed optical communications networks.
    Type: Grant
    Filed: February 19, 1993
    Date of Patent: December 13, 1994
    Assignee: AT&T Corp.
    Inventors: Bernard Glance, Robert W. Wilson
  • Patent number: 5373550
    Abstract: Checks used to effectuate commercial and private transactions may be cleared through the banking system by transporting images of those checks between sending institutions and receiving institutions in forward and reverse flow paths between banks of first deposit and payor banks. The check images are transported through a public switched telephone network which contains a special check imaging node which provides a network based check clearing service for customers of telephone network. The check imaging node receives images of checks from institutions which subscribe to this service and routes those images through the telephone network to intended subscriber and non-subscriber recipients. Transmission of check images through a public switched telephone network may completely replace existing check clearance procedures or may be used in conjunction with existing procedures.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: December 13, 1994
    Assignee: AT&T Corp.
    Inventors: Walter G. Campbell, Charles J. Garland, David A. Hollowell, Robert Orleanski, Carol A. Wegrzynowicz
  • Patent number: 5373517
    Abstract: A monolithically integrated laser which is rapidly tunable over a wide optical frequency range comprises a frequency router formed in a semiconductive wafer defining a tuned cavity. A control circuit applies electrical energy to predetermined controllably transmissive waveguides connecting the frequency routing device with reflective elements defined in the wafer. This tunes the laser to a desired one of a plurality of optical frequencies. Application of such electrical energy creates frequency selective pathways through the wafer able to support selected lasing frequencies. This laser is economical to construct and is useful in high capacity, high speed optical communications networks.
    Type: Grant
    Filed: February 19, 1993
    Date of Patent: December 13, 1994
    Assignee: AT&T Corp.
    Inventors: Corrado Dragone, Ivan P. Kaminow
  • Patent number: 5371780
    Abstract: Fast resource assignments, especially needed in microcellular network architectures having many fast moving subscribers and high traffic volume, is provided through the use of a priority based resource assignment apparatus and procedure. Part of the communications resources in a cellular network, for example, one carrier frequency and/or one time slot, or particular code division multiple access sequences are dedicated to the execution of the assignment procedure. Available communications resources are auctioned to cellular subscribers contending for resources based upon a level of priority assigned to each contending subscriber. The priority level may be based on such things as the quality of service to which a customer subscribes or the particular needs of a subscriber at the time the subscriber is contending for resources, for example, the subscriber's request for resources may be prompted by a need to make a handoff.
    Type: Grant
    Filed: July 28, 1993
    Date of Patent: December 6, 1994
    Assignee: AT&T Corp.
    Inventor: Noach Amitay
  • Patent number: 5355345
    Abstract: A memory is partitioned into rows and columns of memory blocks comprised of latches, sense amplifiers, and logic circuitry that form independent pipelines through which flow a) input addresses for memory access requests and b) data to be written into a specific memory cell within a memory block. The memory allows multiple data access requests in consecutive clock cycles to be pipelined in the rows and columns of memory blocks such that the memory clock speed is equal to the clock speed of a single memory block, independently of the memory size.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: October 11, 1994
    Assignee: AT&T Bell Laboratories
    Inventors: Alexander G. Dickinson, Christopher J. Nicol