Patents by Inventor Zulfiquar Sayeed

Zulfiquar Sayeed 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).

  • Adaptive hybrid ARQ coding schemes for slow fading channels in mobile radio systems
    Patent number: 5828677
    Abstract: A method and apparatus for performing adaptive hybrid automatic repeat request (ARQ) coding in which the coding is modified based on the acknowledgements returned by the receiver. In accordance with one illustrative embodiment of the present invention, the state of the channel is implicitly determined by the transmitter based upon the frequency of acknowledgments (ACKs and NACKs) arriving from the receiver. For example, since a NACK implies a weak received signal strength, the code rate of the FEC is advantageously reduced in response to such an acknowledgement. On the other hand, the code rate of the FEC is advantageously increased in response to an ACK. In accordance with another illustrative embodiment of the present invention, the acknowledgement returned by the receiver is modified to convey the number of errors in the corresponding received data packet.
    Type: Grant
    Filed: March 20, 1996
    Date of Patent: October 27, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: Zulfiquar Sayeed, Vijitha Weerackody