Patents by Inventor James F. Stafford

James F. Stafford 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: 9031602
    Abstract: Techniques are presented herein for load balancing of mobile devices among a plurality of bases stations. Specifically, it is determined via a processor whether to reassign a mobile device from a first base station to a second base station, wherein the second base station is one of a plurality of base stations whose operational performance may be impacted by reassigning the mobile device to the second base station. The expected performance that would result if the mobile device is assigned to the second base station is evaluated for each base station in the plurality. The mobile device is reassigned to the second base station in response to the expected performance of each of the plurality of base stations meeting operational performance requirements.
    Type: Grant
    Filed: October 3, 2012
    Date of Patent: May 12, 2015
    Assignee: Exelis Inc.
    Inventor: James F. Stafford
  • Patent number: 8064499
    Abstract: Common components are used to detect messages from a variety of transmitters, and the characteristics of each detected message are used to dynamically configure the demodulation process for each message. Channelization is selectively performed before, after, or before-and-after de-spreading, depending upon the particular environment and/or the particular characteristics of the received messages. Frequency synchronization to each transmitter is achieved by initializing a tracking loop within the demodulator associated with the transmitter, and code-phase synchronization to each transmitter is achieved by selectively inserting or deleting bits, based on the frequency and code-phase characteristics of the detected message.
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: November 22, 2011
    Assignee: Comtech Mobile Datacom Corporation
    Inventor: James F. Stafford
  • Patent number: 7596170
    Abstract: A receiving system allows for the coherent detection of a spread-spectrum transmission at any point in time during the transmission, thereby avoiding the need to identify the start of the transmission during the transmission-detection process. An input buffer captures the transmissions on a communication channel using a moving time-window. A detector processes a time-slice from the input buffer and identifies all of the simultaneously transmitting transmitters during that time-slice. As each transmitter is identified, the demodulator traces back-in-time to identify where the message can first be detected in the input buffer. The transmission includes suitable characteristics to facilitate detection and demodulation of the message content, but need not contain a preamble to allow the detection process.
    Type: Grant
    Filed: October 22, 2007
    Date of Patent: September 29, 2009
    Assignee: AeroAstro, Inc.
    Inventors: Scott A. McDermott, James F. Stafford, Luis G. Jordan
  • Patent number: 7433391
    Abstract: A receiving system dynamically searches a communications band for transmissions of messages having the same nominal communications parameters, including the use of the same spreading code, but having potentially different specific frequencies and code-phases. The receiver samples the communications band at each code-phase of the spreading code over a span of down-converted transmission frequencies. When a message element is detected at a particular code-phase and frequency, it is forwarded to a demodulator that demodulates the message and sends it to its intended destination. This technique allows each transmitter to be independent of the receiver. In a preferred embodiment of this invention, a Fast M-Sequence Transform (a Walsh-Hadamard Transform) is used to determine the power level at multiple code-phases at a given frequency in parallel, thereby substantially reducing the time required to search for transmissions at each discrete code-phase.
    Type: Grant
    Filed: March 3, 2007
    Date of Patent: October 7, 2008
    Assignee: AeroAstro, Inc.
    Inventors: James F. Stafford, Scott A. McDermott, William F. Seng
  • Publication number: 20080117955
    Abstract: Common components are used to detect messages from a variety of transmitters, and the characteristics of each detected message are used to dynamically configure the demodulation process for each message. Channelization is selectively performed before, after, or before-and-after de-spreading, depending upon the particular environment and/or the particular characteristics of the received messages. Frequency synchronization to each transmitter is achieved by initializing a tracking loop within the demodulator associated with the transmitter, and code-phase synchronization to each transmitter is achieved by selectively inserting or deleting bits, based on the frequency and code-phase characteristics of the detected message.
    Type: Application
    Filed: November 9, 2007
    Publication date: May 22, 2008
    Inventor: James F. Stafford