Drift Correction Patents (Class 708/827)
  • Spectral photon counting detector
    Patent number: 9335424
    Abstract: An apparatus includes an integrator (120) that produces a pulse having a peak amplitude indicative of the energy of a detected photon. First discharging circuitry (136) discharges the integrator (120) at a first discharging speed, and second discharging circuitry (124) discharges the integrator (120) at a second discharging speed. The first discharging speed is less than the second discharging speed.
    Type: Grant
    Filed: May 23, 2008
    Date of Patent: May 10, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventors: Christoph Herrmann, Roger Steadman, Christian Baeumer, Guenter Zeitler
  • MEMS inertial sensor with frequency control and method
    Patent number: 8156805
    Abstract: An inertial sensor has a transducer with a sense resonator. The sense resonator is oscillated. A signal responsive to the oscillation is provided. A first baseband signal and a second baseband signal are provided responsive to the signal responsive to the oscillation of the sense resonator. A signal for controlling a resonance frequency of the sense resonator is provided responsive to performing a Goertzel algorithm on the first baseband signal and the second baseband signal. One use of controlling the resonance frequency is to control an offset between the resonance frequency of the sense resonator and the frequency of the oscillation of drive masses in the sense resonator. Using the Goertzel algorithm is particularly efficient in controlling the resonance frequency.
    Type: Grant
    Filed: April 15, 2009
    Date of Patent: April 17, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventors: David A. Hayner, Keith L. Kraver, Dejan Mijuskovic
  • Method and apparatus for identifying a drift in a quantized signal in a computer system
    Patent number: 7444268
    Abstract: One embodiment of the present invention provides a system that identifies a drift in a signal in a computer system. During operation, the system receives a sequence of quantized signal values of the signal. Next, the system generates a statistical distribution based on the sequence of quantized signal values, wherein the statistical distribution is generated using a set of counters, wherein each counter keeps track of the number of occurrences of an associated quantized signal value. The system periodically adjusts the counters by multiplying each counter by a compression factor if the system determines the sum of the set of counters is greater than or equal to a threshold. The system identifies the drift in the signal by comparing the statistical distribution with a reference distribution of the quantized signal values, wherein the reference distribution is associated with normal operation of the computer system.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: October 28, 2008
    Assignee: Sun Microsystems, Inc.
    Inventors: Praveen Kalamegham, Nathan D. Sportsman, Keith A. Whisnant