Patents by Inventor Frank K. Hwang

Frank K. Hwang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5513379
    Abstract: A communications system and method of ordered borrowing which facilitates dynamic access to a global channel set that has been partitioned into subsets, with each cell of the system being assigned a particular subset of the channel set. The assignment of channel subsets is performed in such a way as to respect various constraints imposed by the physical layout. Calls originating in a cell are first assigned to the channels allocated to the base station of that cell, in an order determined by the cell. Once the allotted channels are exhausted, i.e. in the busy state, the cell attempts to borrow channels from those allotted to the base stations of neighboring cells in a specified order. The borrowing cell borrows a specified number of channels from each neighbor before returning to a particular cell to borrow additional channels. The channels borrowed from a neighbor are accessed in an order which is substantially the reverse of the order in which they are accessed by the owner cell.
    Type: Grant
    Filed: May 4, 1994
    Date of Patent: April 30, 1996
    Assignee: AT&T Corp.
    Inventors: Mathilde Benveniste, Albert G. Greenberg, Frank K. Hwang, Boris D. Lubachevsky, Paul E. Wright
  • Patent number: 5077483
    Abstract: A reduced-blocking system where a perfect shuffle equivalent network having a plurality of node stages successively interconnected by link stages, is advantageously combined with expansion before the node stages and/or concentration after the node stages in a manner allowing the design of a system with arbitrarily low or zero blocking probability. An illustrative photonic system implementation uses free-space optical apparatus to effect a low loss, crossover interconnection of two-dimensional arrays of switching nodes comprising, for example, symmetric self electro-optic effect devices (S-SEEDs). Several low loss beam conbination techniques are used to direct multiple arrays of beams to an S-SEED array, and to redirect a reflected output beam array to a subsequent node stage.
    Type: Grant
    Filed: May 8, 1989
    Date of Patent: December 31, 1991
    Assignee: AT&T Bell Laboratories
    Inventors: Thomas J. Cloonan, Stephen J. Hinterlong, Harvard S. Hinton, Frank K. Hwang, Jurgen Jahns, Jack L. Jewell, Anthony L. Lentine, Frederick B. McCormick, Jr., David A. B. Miller, Miles J. Murdocca, Michael E. Prise, Gaylord W. Richards
  • Patent number: 4989022
    Abstract: A switching network where a large class of combinatorial designs which are well known in the mathematical literature are for the first time applied to advantageously define the pattern of permanent connections effected between network input channels and initial network crosspoints, illustratively by a connection arrangement of a two-stage, rearrangeable network. The class of combinatorial designs comprises designs of three types: (1) block designs, (2) orthogonal arrays, and (3) difference sets. Each of these is used in a unique manner to derive an advantageous pattern of permanent connections.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: January 29, 1991
    Assignee: AT&T Bell Laboratories
    Inventors: Frank K. Hwang, Gaylord W. Richards
  • Patent number: 4988993
    Abstract: A switching network where a large class of combinatorial designs which are well known in the mathematical literature are for the first time applied to advantageously define the pattern of permanent connections effected between network input channels and initial network corsspoints, illustratively by a connection arrangement of a two-stage, rearrangeable network. The class of combinatorial designs comprises designs of three types: (1) block designs, (2) orthogonal arrays, and (3) difference sets. Each of these is used in a unique manner to derive an advantageous pattern of permanent connections.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: January 29, 1991
    Assignee: AT&T Bell Laboratories
    Inventors: Frank K. Hwang, Gaylord W. Richards
  • Patent number: 4944029
    Abstract: A switching network where a large class of combinatorial designs which are well known in the mathematical literature are for the first time applied to advantageously define the pattern of permanent connections effected between network input channels and initial network crosspoints, illustratively by a connection arrangement of a two-stage, rearrangeable network. The class of combinatorial designs comprises designs of three types: (1) block designs, (2) orthogonal arrays, and (3) difference sets. Each of these is used in a unique manner to derive an advantageous pattern of permanent connections.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: July 24, 1990
    Assignee: AT&T Bell Laboratories
    Inventors: Frank K. Hwang, Gaylord W. Richards
  • Patent number: 4922245
    Abstract: A switching network where a large class of combinatorial designs which are well known in the mathematical literature are for the first time applied to advantageously define the pattern of permanent connections effected between network input channels and initial network crosspoints, illustratively by a connection arrangement of a two-stage, rearrangeable network. The class of combinatorial designs comprises designs of three types: (1) block designs, (2) orthogonal arrays, and (3) difference sets. Each of these is used in a unique manner to derive an advantageous pattern of permanent connections.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: May 1, 1990
    Assignee: AT&T Bell Laboratories
    Inventors: Frank K. Hwang, Gaylord W. Richards
  • Patent number: 4914430
    Abstract: A switching network where a large class of combinatorial designs which are well known in the mathematical literature are for the first time applied to advantageously define the pattern of permanent connections effected between network input channels and initial network crosspoints, illustratively by a connection arrangement of a two-stage, rearrangeable network. The class of combinatorial designs comprises designs of three types: (1) block designs, (2) orthogonal arrays, and (3) difference sets. Each of these is used in a unique manner to derive an advantageous pattern of permanent connections.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: April 3, 1990
    Assignee: AT&T Bell Laboratories
    Inventors: Frank K. Hwang, Gaylord W. Richards
  • Patent number: 4887079
    Abstract: A switching network where a large class of combinatorial designs which are well known in the mathematical literature are for the first time applied to advantageously define the pattern of permanent connections effected between network input channels and initial network crosspoints, illustratively by a connection arrangement of a two-stage, rearrangeable network. The class of combinatorial designs comprises designs of three types: (1) block designs, (2) orthogonal arrays, and (3) difference sets. Each of these is used in a unique manner to derive an advantageous pattern of permanent connections.
    Type: Grant
    Filed: December 23, 1986
    Date of Patent: December 12, 1989
    Assignee: AT&T Bell Laboratories
    Inventors: Frank K. Hwang, Gaylord W. Richards