Patents Assigned to Network Access Corporation
  • Patent number: 5416780
    Abstract: A location independent personal telecommunications system is presented that utilizes an out-of-band bi-directional burst data communications network to assist in the routing of personal communications via an in-band voice and data communications network. Access to the out-of-band network for communication is regulated by a multiple access communications protocol. Each user is synchronized with the other users of the network to the protocol and will access the network only during certain time periods that are reserved by the protocol for message traffic between network users. A collision avoidance scheme is included in the protocol to resolve instances of simultaneous transmission of message traffic by multiple users during the same time period.
    Type: Grant
    Filed: April 16, 1992
    Date of Patent: May 16, 1995
    Assignee: Network Access Corporation
    Inventor: Rajendra Patel
  • Patent number: 5315636
    Abstract: The location independent personal telecommunications system of the present invention enables a subscriber to have a single personal telephone directory number. When that personal telephone number is dialed, the system uses the existing public and cellular communication systems and a service node all comprising parts of the personal telecommunications system to route the call to the present, or last known location of the subscriber. The location of the subscriber is determined by the personal telecommunications system through a radio tracking system comprised of a number of radio base stations that monitor the subscriber's location by communicating with a personal communicator carried by the subscriber. The subscriber location information is transmitted from the base stations to the service node for storage and subsequent access when a call is placed to the subscriber's personal telephone number.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: May 24, 1994
    Assignee: Network Access Corporation
    Inventor: Rajendra Patel
  • Patent number: 5233643
    Abstract: A unique combination of frequency and time division multiplexed communications is presented to enable bi-directional burst communications between a substantial number of users over a single radio frequency communications channel. A service area for communications is divided into a number of cells, with the cells arranged into clusters. Cells in each cluster are similarly numbered with no two adjacent cells across the service area having the same number. The clusters are also numbered in the same manner. A cellular time division multiplexed waveform is used by the network to carry communications with each cell number and cluster number assigned a time slot. During the time slot corresponding to the cell or cluster number, all cells or clusters having that number will be simultaneously transmitting. This networking technique enables time slots to be reused across the service area.
    Type: Grant
    Filed: October 8, 1991
    Date of Patent: August 3, 1993
    Assignee: Network Access Corporation
    Inventors: Abdolreza S. Naeini, Rajendra Patel, Marion K. Vaughn, Jr.
  • Patent number: 5086461
    Abstract: The invention relates to upgrading existing telephone central offices having 1ESS or 1AESS switching equipment to utilize the SS7 protocol. In particular, the 1ESS and 1AESS switching equipment is provided with the capability of controlling the connection, management, and disconnection of telephone circuits using Signaling System Number 7 (SS7), a national and international standard set of protocols for providing such circuit control and providing and receiving information via the SS7 protocol for enabling enhanced service in the switching equipment.
    Type: Grant
    Filed: January 23, 1990
    Date of Patent: February 4, 1992
    Assignee: Network Access Corporation
    Inventors: David W. Thorn, Rajendra Patel, Gordon Sohl
  • Patent number: 4903263
    Abstract: The invention relates to upgrading existing telephone central offices which utilize electromechanical or electronic switching equipment to include the capability of processing calls in the ISDN protocol. In particular, it relates to providing said switching equipment with the capability of controlling the connection, management, and disconnection of telephone circuits using Integrated Services Digital Network (ISDN), a national and international standard set of protocols for providing such circuit control and providing and receiving information via the ISDN protocol for enabling enhanced service in the switching equipment.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: February 20, 1990
    Assignee: Network Access Corporation
    Inventors: Rajendra Patel, Girish Patel
  • Patent number: 4853955
    Abstract: The invention relates to upgrading existing telephone central offices which utilize electromechanical or electronic switching equipment incapable of using the SS7 protocol. In particular, it relates to providing the switching equipment with the capability of controlling the connection, management, and disconnection of telephone circuits using Signaling System Number 7, a national and international standard set of protocols for providing such circuit control and providing and receiving information via the SS7 protocol for enabling enhanced service in the switching equipment.
    Type: Grant
    Filed: April 27, 1988
    Date of Patent: August 1, 1989
    Assignee: Network Access Corporation
    Inventors: David W. Thorn, Rajendra Patel, Gerald Coley, Ashok Trivedi, Girish Patel
  • Patent number: 4782519
    Abstract: A method and apparatus is described for providing extended subscriber features, e.g., equal access, to otherwise non-conforming central offices of a telephone switching system. According to the invention, a register module is interposed between the subscriber line and an input of the central office for intercepting digits from the subscriber line intended for the central office and for receiving subscriber information from the central office identifying the subscriber line. The register module includes a memory having a plurality of address locations and a control circuit for analyzing the intercepted digits to determine whether processing of the subscriber call requires an extended subscriber feature. If so, the intercepted digits are processed to generate a coded signal, the coded signal including the address location where the stored digits and the subscriber information resides in the memory.
    Type: Grant
    Filed: May 22, 1986
    Date of Patent: November 1, 1988
    Assignee: Network Access Corporation
    Inventors: Rajendra Patel, Kenneth A. Lauffenburger, David W. Thorn, Donald D. Binford, Jr., Zye-Kong Cheng, Yeong-Haw Yang, Gerald K. Coley, Charles C. Miller