Patents by Inventor Dimitrios Hatzipapafotiou

Dimitrios Hatzipapafotiou 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).

  • Enhanced access burst for random access channels in TDMA mobile satellite system
    Patent number: 5875182
    Abstract: A spacecraft (12) cellular TDMA communications system (10) includes many user terminals (16), some of which may be movable. The spacecraft repeats transmissions by way of spot beams (20). A user initiates communication by synchronizing to the TDMA slots (210, 212), and transmits an access request signal. The access request signal is transmitted in at least two slots. The first slot contains time and frequency PN synch information, and the second slot contains one of (a) the user terminal's ID code and (b) a code representing the desired type of access. After this message is transmitted and received, the user terminal may transmit the PN synch information on a third slot, followed by the other one of the user terminal's ID code and the access-representative code.
    Type: Grant
    Filed: January 16, 1997
    Date of Patent: February 23, 1999
    Assignee: Lockheed Martin Corporation
    Inventor: Dimitrios Hatzipapafotiou