Patents by Inventor Charles E. Sigler

Charles E. Sigler 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: 6035039
    Abstract: In a mobile satellite system, a mobile communication system includes a fraud detection and user validation system and method for commissioning the mobile communication system in the mobile satellite system. The method includes the steps of generating a first input signal by the mobile communication system upon initialization, and transmitting the first input signal from the mobile communication system to the central controller. The method also includes the steps of generating a first security key in the central controller using the first input signal, and generating a second security key in the mobile communication system using the first input signal and transmitting the second security key to the central controller. The central controller verifies the mobile communication system that transmitted the first input signal to commission it in the mobile satellite system. The verification process is responsive to a comparison of the first security key with the second security key.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: March 7, 2000
    Inventors: William R. Tisdale, Charles E. Sigler
  • Patent number: 5748742
    Abstract: In a mobile satellite system, a mobile communication system includes a fraud detection and user validation system and method for commissioning the mobile communication system in the mobile satellite system. The method includes the steps of generating a first input signal by the mobile communication system upon initialization, and transmitting the first input signal from the mobile communication system to the central controller. The method also includes the steps of generating a first security key in the central controller using the first input signal, and generating a second security key in the mobile communication system using the first input signal and transmitting the second security key to the central controller. The central controller verifies the mobile communication system that transmitted the first input signal to commission it in the mobile satellite system. The verification process is responsive to a comparison of the first security key with the second security key.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: May 5, 1998
    Assignee: AMSC Subsidiary Corporation
    Inventors: William R. Tisdale, Charles E. Sigler
  • Patent number: 5708716
    Abstract: An authentication system authenticates a mobile communication system each time it attempts to register or communication in a mobile satellite system. The authentication system stores a first security key to establish communication in the mobile communication network system. The system generates a second security key having first and second components using a first process having first and second input signals. The first input signal includes the first security key, and the second input signal includes at least one of a transmit frequency and a receive frequency. The system generates a third security key using a second process having third and fourth input signals. The third input signal includes the second component of the second security key and the fourth input signal is a random number. Advantageously, the system verifies that the mobile communication system is authorized to establish communication using at least one of the first, second, third and fourth components of the second and third security keys.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: January 13, 1998
    Assignee: AMSC Subsidiary Corporation
    Inventors: William R. Tisdale, Charles E. Sigler