Patents by Inventor Srinivasa H. Raghavan

Srinivasa H. Raghavan 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: 7586972
    Abstract: A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and staggered Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.
    Type: Grant
    Filed: February 11, 2004
    Date of Patent: September 8, 2009
    Assignee: The Aerospace Corporation
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes, Kristine P. Maine
  • Patent number: 7139302
    Abstract: A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.
    Type: Grant
    Filed: November 18, 2002
    Date of Patent: November 21, 2006
    Assignee: The Aerospace Corporation
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes, Kris P. Maine
  • Publication number: 20040161019
    Abstract: A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and staggered Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.
    Type: Application
    Filed: February 11, 2004
    Publication date: August 19, 2004
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes, Kristine P. Maine
  • Publication number: 20040095989
    Abstract: A code division multiple access (CDMA) communication system using spread spectrum signaling over a communication bandwidth uses two different signal spectra generated using two different respective spreading code formats, such as NRZ code formatting and Manchester code formatting, for respectively providing nonsplit spectra having a center peak and split spectra having a center null. The spectra are combined during transmission as a CDMA communication signal having a composite spectrum. The use of different code formats produces the composite spectrum of respective center peak and center null spectra that enables increased channel capacity.
    Type: Application
    Filed: November 18, 2002
    Publication date: May 20, 2004
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes, Kris P. Maine
  • Patent number: 6148022
    Abstract: An NRZ and biphase-L formatted, quadriphase modulated GPS signal transmission communication method provides for the simultaneous modulation of two CDMA spread spectrum codes such as the GPS C/A code and either the P(Y) code, or an arbitrary NEW code modulating a single carrier for GPS use in one or both L1 and L2 bands. The use of NRZ formatting and biphase-L formatting provides spectral separation even though both spread spectrum signals are modulated onto the same carrier.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: November 14, 2000
    Assignee: The Aerospace Corporation
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes
  • Patent number: 6075810
    Abstract: An NRZ and biphase-L formatted, three code hexaphase modulated GPS signal transmission communication method provides for the simultaneous modulation of the C/A code, the P(Y) code and a NEW code all modulating a single carrier for GPS use in one or both L1 and L2 bands. The use of the C/A code and the P(Y) code which are NRZ formatted with a NEW code biphase-L formatted and using hexaphase modulation on the three signals provides for spectral separation between the C/A code signal and the NEW code signal, all three modulated on a single carrier frequency.
    Type: Grant
    Filed: January 28, 1998
    Date of Patent: June 13, 2000
    Assignee: The Aerospace Corporation
    Inventors: Srinivasa H. Raghavan, Jack K. Holmes