Patents Assigned to AT&T Company
  • Patent number: 4656627
    Abstract: A packet switching system having separate arbitration and data buses together with circuitry for dividing the buses into a plurality of time segments termed phases. The plurality of phases permit a like plurality of separate arbitration operations and a like plurality of separate data exchanges to be effected concurrently on the arbitration bus and data bus, respectively. The use of n phases increases the data transmission capability of the system by a factor of n over prior art arrangements using only a single phase.
    Type: Grant
    Filed: November 21, 1984
    Date of Patent: April 7, 1987
    Assignees: AT&T Company, AT&T Information Systems Inc.
    Inventors: Lloyd A. Hasley, Jaan Raamot
  • Patent number: 4653085
    Abstract: The adjunct call processing arrangement of our invention eliminates the separation between hard-wired telephone switching system computer facilities and customer owned switchably connectable computer facilities. A general purpose communication interface is provided which connects the customer provided computer facilities to both the switching network and the hard-wired system processor of the telephone switching system via the standard telephone switching system port circuit. This general purpose communication interface enables a customer provided computer facility to provide additional call processing capability. In particular, the attendant services call processing subroutines and the directory assistance data base and software are provided on the computer facility. The telephone switching system routes all attendant-directed calls to a telephone station set associated with the computer and transmits call related data to the computer.
    Type: Grant
    Filed: September 27, 1984
    Date of Patent: March 24, 1987
    Assignees: AT&T Company, AT&T Information Systems Inc.
    Inventors: Norman C. Chan, Leif K. Pederson
  • Patent number: 4652733
    Abstract: The present invention relates to a technique for automatically cataloging and storing pictorial and/or written sections of information in the form of, for example 35-mm slides, X-rays, store catalog pages, etc. in a database for subsequent retrieval by end users of the database. In accordance with the present technique, a bar-code label, including a unique bar-code, is assigned and affixed to each piece or section of information to be separately stored in the database. Each section of information is sequentially fed into a recording arrangement where (a) the bar-code versus a brief description of the information section is recorded in a computer memory, (b) an image of the pictorial and/or written information section is transformed into a video signal and recorded on a separate location of a video tape or disk, and (c) the location of the video signal on the video tape or disk for each section of information is recorded in the computer memory with the associated bar-code and brief description.
    Type: Grant
    Filed: October 15, 1984
    Date of Patent: March 24, 1987
    Assignees: AT&T Company, AT&T Bell Laboratories
    Inventors: Kai Y. Eng, On-Ching Yue
  • Patent number: 4651103
    Abstract: Synchronization facilities are disclosed for maintaining error free timing of a digital system when control of the system timing is switched between a plurality of clock sources. The signal of each source is applied to an associated counter divider whose output is applied to switch facilities which extend the output of only one divider at a time as a reference clock source to the digital system. The dividers for the other sources are forcibly reset each time the divider of the reference source advances from its all 1s to its reset (all 0s) position. This maintains the output signals of all dividers in phase with each other to prevent disturbances to the digital system when its timing is switched between clock sources.
    Type: Grant
    Filed: December 30, 1985
    Date of Patent: March 17, 1987
    Assignees: AT&T Company, AT&T Information Systems Inc.
    Inventor: Gary J. Grimes
  • Patent number: 4646346
    Abstract: This integrated message service system provides a user with an indication of which of a plurality of message service systems contain unretrieved messages. This is accomplished by the serving telephone switching system maintaining a translation memory that indicates both the type of message services assigned to each user and the location of unretrieved messages in the assigned message services. The translation memory is updated every time a user creates a new message or accesses a previously stored message.
    Type: Grant
    Filed: January 22, 1985
    Date of Patent: February 24, 1987
    Assignees: AT&T Company, AT&T Information Systems Inc.
    Inventors: William D. Emerson, Deborah J. Hill, Karen C. Loeb, Albert Mizrahi, Charles T. Schlegel, Lowell C. Scott
  • Patent number: 4644562
    Abstract: Data-aided equalization and cancellation in digital data transmission over dually polarized fading radio channels is disclosed. The present invention uses decision feedback structures with finite-tap transversal filters. Subject to the assumption that some past and/or future data symbols are correctly detected, formulas and algorithms for evaluating the least mean-square error for different structures are disclosed. In a sequence of curves, the performance of various structures for a particular propagation model and several fading events are evaluated and compared.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: February 17, 1987
    Assignees: AT&T Company, AT&T Bell Laboratories
    Inventors: Mohsen Kavehrad, Jack Salz
  • Patent number: 4643521
    Abstract: An optical rotary joint has a first pair of light beam expanding graded index (GRIN) of refraction lenses coupled to ends of a first pair of lightguide fibers for coupling signals through the rotary joint interface in a first path which is coaxial with the axis of rotation in the interface. A second pair of lightguide fibers are coupled to a second pair of GRIN lenses off-axis and of much smaller diameter than the lenses of the first pair. Prisms couple signals between the off-axis lenses and a second path across the interface and which is also coaxial with the axis of rotation. Also shown is a method for compensating for lens irregularities.
    Type: Grant
    Filed: July 5, 1984
    Date of Patent: February 17, 1987
    Assignees: AT&T Company, AT&T Bell Laboratories
    Inventors: Edward E. Harstead, Leon Klafter, Yan-Chi Shi
  • Patent number: 4641299
    Abstract: In a telephone local exchange system where loops are connected to a remote switch which in turn homes on a host switch via a carrier system and where the distance between the ends of the loops and the host switch exceeds a threshold, the loops may be tested by locating the test apparatus remotely from the host switch so that the distance between the free ends of the loops and the test apparatus is below the threshold and so that a metallic pair of conductors may be used therebetween to permit some tests which cannot be done using carrier facilities. In order to establish a connection between the test apparatus and the loops, signals are transferred over two dedicated carrier channels between the test apparatus and the host switch via two applique circuits. These applique circuits make it appear to the test system as if the remote switch (or carrier RT or concentrator) support a test trunk.
    Type: Grant
    Filed: September 21, 1984
    Date of Patent: February 3, 1987
    Assignees: AT&T Company, AT&T Bell Laboratories
    Inventors: Kyran B. Kemper, Robert W. Vetter, Jr.
  • Patent number: 4207906
    Abstract: A method of making a cigarette having a core of one grade of tobacco and at least one substantially circumferential wrapping of a second grade of tobacco which comprises applying to a moving base or conveyor a first stream of the core tobacco and a pair of second streams of the wrapping material, one stream of wrapping material being on either side of the first stream. The three streams are then deposited onto a moving support which is at an angle to the base such that one stream of wrapping material is deposited upstream of the core material which, in turn, is deposited upstream of the other stream of wrapping material. The composite layer thus formed is then formed into a tobacco cord in a known manner. The latter is then formed into cigarettes in the usual way.A modification of known cigarette-making machines is described which is particularly adapted for carrying out this method.
    Type: Grant
    Filed: January 17, 1978
    Date of Patent: June 17, 1980
    Assignee: B.A.T. Company Limited
    Inventors: Friedlieb Seehofer, Helmut Kalies