Patents by Inventor Refet Firat Yazicioglu

Refet Firat Yazicioglu 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: 8755868
    Abstract: A method and apparatus is disclosed for adaptively sampling an analogue signal to increase the sampling rate in the presence of high frequency content within the signal, for example, QRS complex of an ECG signal. In one aspect, a change in a derivative of the analogue signal is used to control a voltage-controlled oscillator to provide a clock signal for an analogue-to-digital converter. The change in the derivative is compared to an automatically controlled threshold value. The clock signal controls the sampling rate of the analogue-to-digital converter so that the sampling rate is increased from one level, where only P and T waves are present to another higher level when the QRS complex has been detected.
    Type: Grant
    Filed: September 14, 2010
    Date of Patent: June 17, 2014
    Assignee: IMEC
    Inventor: Refet Firat Yazicioglu
  • Patent number: 8466742
    Abstract: The present invention relates to a large time constant steering circuit for slowly changing a voltage on a node between at least two discrete voltage levels. The present invention further relates to a slow steering current DAC comprising said large time constant steering circuit. The present invention further relates to an instrumentation amplifier device comprising a current balancing instrumentation amplifier for amplifying an input signal to an amplified output signal and a DC servo-loop for removing a DC-component from the input signal. The present invention further relates to an EEG acquisition ASIC comprising said instrumentation amplifier device.
    Type: Grant
    Filed: February 25, 2011
    Date of Patent: June 18, 2013
    Assignees: IMEC, Katholieke Universiteit Leuven, K.U. Leuven R&D
    Inventors: Refet Firat Yazicioglu, Patrick Merken
  • Patent number: 8454505
    Abstract: A method and device is disclosed for continuously and simultaneously measuring an impedance signal and a biopotential signal on a biological subject's skin. In one aspect, the method includes attaching input and output electrodes to the biological subject's skin and applying a predetermined alternating current having a first frequency to the output electrodes for creating an alternating voltage signal over the input electrodes. The first frequency is above a predetermined minimum frequency. The method also includes measuring an input signal from the input electrodes which includes a biopotential signal and the alternating voltage signal. The method also includes extracting from the input signal the biopotential signal and the alternating voltage signal, and determining the impedance signal from the alternating voltage signal. The alternating voltage signal is extracted by amplifying and demodulating the input signal using a control signal having a frequency equal to the first frequency.
    Type: Grant
    Filed: September 14, 2010
    Date of Patent: June 4, 2013
    Assignee: IMEC
    Inventors: Refet Firat Yazicioglu, Sunyoung Kim
  • Publication number: 20120095361
    Abstract: A multi-channel biopotential signal acquisition system is disclosed. In the system, a plurality of biopotential channels is corrected for common-mode interference. In one aspect, each biopotential channel includes an electrode for providing a biopotential input signal and an associated amplifier for amplifying the biopotential input signal and providing a biopotential output signal. The output signal is processed in a processor. Each biopotential output signal is passed to a common-mode feedback system, which determines an average common-mode signal and feeds that signal back to each of the amplifiers in each of the biopotential channels to enhance common-mode rejection ratio of the system.
    Type: Application
    Filed: September 7, 2011
    Publication date: April 19, 2012
    Applicants: Stichting IMEC Nederland, IMEC
    Inventors: Jiawei XU, Refet Firat Yazicioglu
  • Publication number: 20110193623
    Abstract: The present invention relates to a large time constant steering circuit for slowly changing a voltage on a node between at least two discrete voltage levels. The present invention further relates to a slow steering current DAC comprising said large time constant steering circuit. The present invention further relates to an instrumentation amplifier device comprising a current balancing instrumentation amplifier for amplifying an input signal to an amplified output signal and a DC servo-loop for removing a DC-component from the input signal. The present invention further relates to an EEG acquisition ASIC comprising said instrumentation amplifier device.
    Type: Application
    Filed: February 25, 2011
    Publication date: August 11, 2011
    Applicants: IMEC, KATHOLIEKE UNIVERSITEIT LEUVEN
    Inventors: Refet Firat Yazicioglu, Patrick Merken
  • Publication number: 20110092834
    Abstract: An analogue signal processor (ASP) application-specific integrated circuit (ASIC) is disclosed. The ACIS can be used for remotely monitoring ECG signals of a subject that has reduced power consumption. In one aspect, the ASIC performs the functions of: ECG signal extraction with high resolution using ECG readout channel, feature extraction using a band-power extraction channel, adaptive sampling the ECG signals using an adaptive sampling analogue-to-digital converter, and impedance monitoring for signal integrity using an impedance monitoring channel. These functions enable the development of wireless ECG monitoring systems that have significantly lower power consumption but are more efficient that predecessor systems. In one embodiment, the ASP ASIC consumes 30 ?W from a 2V supply with compression provided by adaptive sampling providing large reductions in power consumption of a wireless ECG monitoring system of which the ASP ASIC forms a part.
    Type: Application
    Filed: September 14, 2010
    Publication date: April 21, 2011
    Applicants: IMEC, Stichting IMEC Nederland
    Inventors: Refet Firat YAZICIOGLU, Julien PENDERS, Sunyoung KIM
  • Patent number: 7920005
    Abstract: The present invention relates to a large time constant steering circuit for slowly changing a voltage on a node between at least two discrete voltage levels. The present invention further relates to a slow steering current DAC comprising said large time constant steering circuit. The present invention further relates to an instrumentation amplifier device comprising a current balancing instrumentation amplifier for amplifying an input signal to an amplified output signal and a DC servo-loop for removing a DC-component from the input signal. The present invention further relates to an EEG acquisition ASIC comprising said instrumentation amplifier device.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: April 5, 2011
    Assignees: IMEC, Katholieke Universiteit Leuven K.U., Leuven R&D
    Inventors: Refet Firat Yazicioglu, Patrick Merken
  • Publication number: 20110066053
    Abstract: A method and apparatus is disclosed for adaptively sampling an analogue signal to increase the sampling rate in the presence of high frequency content within the signal, for example, QRS complex of an ECG signal. In one aspect, a change in a derivative of the analogue signal is used to control a voltage-controlled oscillator to provide a clock signal for an analogue-to-digital converter. The change in the derivative is compared to an automatically controlled threshold value. The clock signal controls the sampling rate of the analogue-to-digital converter so that the sampling rate is increased from one level, where only P and T waves are present to another higher level when the QRS complex has been detected.
    Type: Application
    Filed: September 14, 2010
    Publication date: March 17, 2011
    Applicant: IMEC
    Inventor: Refet Firat YAZICIOGLU
  • Publication number: 20110066054
    Abstract: A method and device is disclosed for continuously and simultaneously measuring an impedance signal and a biopotential signal on a biological subject's skin. In one aspect, the method includes attaching input and output electrodes to the biological subject's skin and applying a predetermined alternating current having a first frequency to the output electrodes for creating an alternating voltage signal over the input electrodes. The first frequency is above a predetermined minimum frequency. The method also includes measuring an input signal from the input electrodes which includes a biopotential signal and the alternating voltage signal. The method also includes extracting from the input signal the biopotential signal and the alternating voltage signal, and determining the impedance signal from the alternating voltage signal. The alternating voltage signal is extracted by amplifying and demodulating the input signal using a control signal having a frequency equal to the first frequency.
    Type: Application
    Filed: September 14, 2010
    Publication date: March 17, 2011
    Applicant: IMEC
    Inventors: Refet Firat Yazicioglu, Sunyoung Kim
  • Publication number: 20090195319
    Abstract: The present invention relates to a large time constant steering circuit for slowly changing a voltage on a node between at least two discrete voltage levels. The present invention further relates to a slow steering current DAC comprising said large time constant steering circuit. The present invention further relates to an instrumentation amplifier device comprising a current balancing instrumentation amplifier for amplifying an input signal to an amplified output signal and a DC servo-loop for removing a DC-component from the input signal. The present invention further relates to an EEG acquisition ASIC comprising said instrumentation amplifier device.
    Type: Application
    Filed: January 30, 2009
    Publication date: August 6, 2009
    Applicants: Interuniversitair Microelektronica Centrum (IMEC), Katholieke Universiteit Leuven
    Inventors: Refet Firat Yazicioglu, Patrick Merken