Patents by Inventor Alpaslan Demir

Alpaslan Demir 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: 7746920
    Abstract: A method of generating an index value associated with a primary synchronization code within a communication signal includes splitting a sampled communication signal into even and odd samples. The even and odd samples are correlated with a primary synchronization code of the communication signal and complex values of the even and odd samples are generated. Signal strength values for the even and odd samples are approximated and the approximate signal strength values within a frame of the communication signal are accumulated. A highest accumulated signal strength value is assigned as an index value.
    Type: Grant
    Filed: October 6, 2008
    Date of Patent: June 29, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: Alpaslan Demir, Donald M Grieco
  • Patent number: 7724817
    Abstract: A step-size estimator for controlling the step-size of an adaptive equalizer incorporated in a transceiver (e.g., a wireless transmit/receive unit (WTRU)). The step-size estimator updates at least one adaptive equalizer tap used by the adaptive equalizer based on an apparent speed of a channel established between the transceiver and another transceiver. The step-size estimator includes a speed estimator, a signal-to-noise ratio (SNR) averager and a step-size mapping unit. The speed estimator is used to estimate the apparent speed of the channel (i.e., the observed and/or measured rate of change of the channel impulse response). The SNR averager generates a common pilot channel (CPICH) SNR estimate. The step-size mapping unit uses the speed estimate and the CPICH SNR estimate to generate a step-size parameter, ?, and a filter taps leakage factor parameter, ?, used by the adaptive equalizer to update the filter tap coefficient.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: May 25, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: Philip J. Pietraski, Mihaela C. Beluri, Alpaslan Demir
  • Patent number: 7702288
    Abstract: In order to compensate for performance degradation caused by inferior low-cost analog radio component tolerances of an analog radio, a wireless communication transmitter employs a control process to implement numerous digital signal processing (DSP) techniques to compensate for deficiencies of such analog components so that modern specifications may be relaxed. By monitoring a plurality of parameters associated with the analog radio, such as temperature, bias current or the like, enhanced phase and amplitude compensation, as well as many other radio frequency (RF) parameters may be implemented.
    Type: Grant
    Filed: November 1, 2006
    Date of Patent: April 20, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: Alpaslan Demir, Leonid Kazakevich, Kenneth P. Kearney
  • Patent number: 7689235
    Abstract: A method for performing initial cell search in wireless communication system wherein unsuitable cells includes searching stored frequencies exhaustively and initial frequencies non-exhaustively. Initial frequencies may be searched exhaustively in certain circumstances. When performing exhaustive initial cell searches, primary synchronization codes that lead to unsuitable cells are excluded from subsequent initial cell searches performed on the same frequency.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: March 30, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: Alpaslan Demir, Donald M. Grieco, John W. Haim, Andrew F. Bednarz
  • Patent number: 7672398
    Abstract: A method and system for determining amplitude and phase compensation values used to adjust the amplitude and phase characteristics of real and imaginary signal components of complex signals processed by an analog radio transmitter. The compensation values may be determined in response to detecting a significant temperature change in the transmitter. Corresponding amplitude and phase adjustment signals having levels that correspond to the compensation values are provided to respective amplitude and phase imbalance compensation modules to adjust the amplitude and phase characteristics of at least one of the real and imaginary signal components.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: March 2, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: Alpaslan Demir, Leonid Kazakevich, Kenneth P. Kearney
  • Publication number: 20100020751
    Abstract: A wireless transmit receive unit (WTRU) provides facilitation of cell search. In one embodiment, received samples are split into a plurality of sample sets for processing. Each of the sets is processed and an accumulated result is divided by an estimated noise value. In another embodiment, a code correlator correlates the received signal with a primary synchronization code and an auxiliary code correlator having a same length as the code correlator correlates the received signal with a code having a low cross correlation with the primary synchronization code. In another embodiment, a division of an accumulated result with a noise estimate is performed using indexes of the most significant bits.
    Type: Application
    Filed: October 1, 2009
    Publication date: January 28, 2010
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Philip J. Pietraski, Alpaslan Demir, Donald M. Grieco
  • Publication number: 20100004018
    Abstract: A method and system for adjusting the amplitude and phase characteristics of wireless communication signals generated by an analog radio transmitter, based on transmit power control (TPC) signals received by a base station (BS) and known characteristics of a power amplifier (PA) included in the transmitter. A digital pre-distortion compensation module, having real and imaginary signal paths, receives and processes real and imaginary signal components used to generate the wireless communication signal. The phase and amplitude characteristics of the wireless communication signal are controlled in response to the TPC signals, such that impaired amplitude and phase characteristics of the PA are corrected.
    Type: Application
    Filed: September 14, 2009
    Publication date: January 7, 2010
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Alpaslan Demir, Leonid Kazakevich, Geetha L. Narayan
  • Patent number: 7627020
    Abstract: A User Equipment (UE) receives and samples communication signals, where the communication signals have a time frame format, a transmission chip rate and a synchronization code associated with a time slot that includes a midamble that indicates a modulation of the synchronization code where a specified modulation of received synchronization codes identifies the timing for a timeslot in which data is to be received. The UE preferably includes a synchronization code determination circuit, a midamble determination circuit, and a phase modulation sequence detection circuit operatively associated with the midamble determination circuit. The UE can be configured for use with the low chip rate option of the Third Generation Partnership Project (3GPP) Universal Mobile Telecommunication System (UMTS) standards that employ a predefined set of downlink SYNC codes that point to midambles which indicate SYNC code modulation sequence to enables reading of data in a subsequent Broadcast Channel (BCH) message.
    Type: Grant
    Filed: July 21, 2008
    Date of Patent: December 1, 2009
    Assignee: InterDigital Technology Corporation
    Inventors: Alpaslan Demir, Fatih M. Ozluturk
  • Publication number: 20090290630
    Abstract: An adaptive equalizer including an equalizer filter and a tap coefficients generator used to process a sample data stream derived from a plurality of received signals is disclosed. The tap coefficients generator includes an equalizer tap update unit, a vector norm square estimator, an active taps mask generator, a switch and a pilot amplitude reference unit used to minimize the dynamic range of the equalizer filter. A dynamic mask vector is used to mask active taps generated by the equalizer tap update unit when an unmasked signal output by the equalizer filter is selected by the switch to generate an error signal fed to the equalizer tap update unit. A fixed mask vector is used to mask active taps generated by the equalizer tap update unit when a masked signal output by the equalizer filter is used to generate the error signal.
    Type: Application
    Filed: July 30, 2009
    Publication date: November 26, 2009
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Philip J. Pietraski, Mihaela Beluri, Alpaslan Demir, Jung-Lin Pan, Gregory S. Sternberg, Rui Yang, Bin Li
  • Patent number: 7609785
    Abstract: A wireless transmit receive unit (WTRU) provides facilitation of cell search. In one embodiment, received samples are split into a plurality of sample sets for processing. Each of the sets is processed and an accumulated result is divided by an estimated noise value. In another embodiment, a code correlator correlates the received signal with a primary synchronization code and an auxiliary code correlator having a same length as the code correlator correlates the received signal with a code having a low cross correlation with the primary synchronization code. In another embodiment, a division of an accumulated result with a noise estimate is performed using indexes of the most significant bits.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: October 27, 2009
    Assignee: InterDigital Technology Corporation
    Inventors: Philip J. Pietraski, Alpaslan Demir, Donald M. Grieco
  • Patent number: 7570690
    Abstract: An adaptive equalizer including an equalizer filter and a tap coefficients generator used to process a sample data stream derived from a plurality of received signals is disclosed. The tap coefficients generator includes an equalizer tap update unit, a vector norm square estimator, an active taps mask generator, a switch and a pilot amplitude reference unit used to minimize the dynamic range of the equalizer filter. A dynamic mask vector is used to mask active taps generated by the equalizer tap update unit when an unmasked signal output by the equalizer filter is selected by the switch to generate an error signal fed to the equalizer tap update unit. A fixed mask vector is used to mask active taps generated by the equalizer tap update unit when a masked signal output by the equalizer filter is used to generate the error signal.
    Type: Grant
    Filed: November 2, 2005
    Date of Patent: August 4, 2009
    Assignee: InterDigital Technology Corporation
    Inventors: Philip J. Pietraski, Mihaela Beluri, Alpaslan Demir, Jung-Lin Pan, Gregory S. Sternberg, Rui Yang, Bin Li
  • Publication number: 20090129458
    Abstract: A step-size estimator for controlling the step-size of an adaptive equalizer incorporated in a transceiver (e.g., a wireless transmit/receive unit (WTRU)). The step-size estimator updates at least one adaptive equalizer tap used by the adaptive equalizer based on an apparent speed of a channel established between the transceiver and another transceiver. The step-size estimator includes a speed estimator, a signal-to-noise ratio (SNR) averager and a step-size mapping unit. The speed estimator is used to estimate the apparent speed of the channel (i.e., the observed and/or measured rate of change of the channel impulse response). The SNR averager generates a common pilot channel (CPICH) SNR estimate. The step-size mapping unit uses the speed estimate and the CPICH SNR estimate to generate a step-size parameter, ?, and a filter taps leakage factor parameter, ?, used by the adaptive equalizer to update the filter tap coefficient.
    Type: Application
    Filed: January 27, 2009
    Publication date: May 21, 2009
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Philip J. Pietraski, Mihaela C. Beluri, Alpaslan Demir
  • Publication number: 20090074108
    Abstract: A method and system for determining amplitude and phase compensation values used to adjust the amplitude and phase characteristics of real and imaginary signal components of complex signals processed by an analog radio transmitter. The compensation values may be determined in response to detecting a significant temperature change in the transmitter. Corresponding amplitude and phase adjustment signals having levels that correspond to the compensation values are provided to respective amplitude and phase imbalance compensation modules to adjust the amplitude and phase characteristics of at least one of the real and imaginary signal components.
    Type: Application
    Filed: November 21, 2008
    Publication date: March 19, 2009
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Alpaslan Demir, Leonid Kazakevich, Kenneth P. Kearney
  • Publication number: 20090060020
    Abstract: A method and apparatus for estimating and correcting baseband frequency error in a receiver. In one embodiment, an equalizer performs equalization on a sample data stream and generates filter tap values based on the equalization. An estimated frequency error signal is generated based on at least one of the filter tap values. A rotating phasor is generated based on the estimated frequency error signal. The rotating phasor signal is multiplied with the sample data stream to correct the frequency of the sample data stream. In another embodiment, a channel estimator performs channel estimation and generates Rake receiver finger weights based on at least one of the finger weights. An estimated frequency error signal is generated based on at least one of the finger weights.
    Type: Application
    Filed: November 6, 2008
    Publication date: March 5, 2009
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Philip J. Pietraski, Rui Yang, Mihaela Beluri, Alpaslan Demir
  • Publication number: 20090054094
    Abstract: A method and apparatus for identifying a code group representative of a predetermined number of base stations is disclosed. A chip offset within a frame is input into a first correlator. A plurality of samples of chips at which a primary synchronization code (PSC) has been detected are input into the first correlator. Output of the first correlator is multiplied by the complex conjugate of the PSC to obtain a magnitude for the signals being transmitted at the chips inputted into the first correlator. The magnitude is summed over four frames. The summed signals view of a predetermined set of decision variables is evaluated. A case number, a code group, a timeslot location, and a system frame number are determined based on the evaluation and noise estimation.
    Type: Application
    Filed: October 27, 2008
    Publication date: February 26, 2009
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Alpaslan Demir, Donald M. Grieco, John W. Haim, Andrew F. Bednarz, Philip J. Pietraski, Louis J. Guccione, Prabhakar R. Chitrapu
  • Patent number: 7496138
    Abstract: A step-size estimator for controlling the step-size of an adaptive equalizer incorporated in a transceiver, (e.g., a wireless transmit/receive unit (WTRU)). The step-size estimator updates at least one adaptive equalizer tap used by the adaptive equalizer based on an apparent speed of a channel established between the transceiver and another transceiver. The step-size estimator includes a speed estimator, a signal-to-noise ratio (SNR) averager and a step-size mapping unit. The speed estimator is used to estimate the apparent speed of the channel, (i.e., the observed and/or measured rate of change of the channel impulse response). The SNR averager generates a common pilot channel (CPICH) SNR estimate. The step-size mapping unit uses the speed estimate and the CPICH SNR estimate to generate a step-size parameter, ?, and a filter taps leakage factor parameter, ?, used by the adaptive equalizer to update the filter tap coefficient.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: February 24, 2009
    Assignee: InterDigital Technology Corporation
    Inventors: Philip J. Pietraski, Mihaela Beluri, Alpaslan Demir
  • Publication number: 20090034670
    Abstract: A method of generating an index value associated with a primary synchronization code within a communication signal includes splitting a sampled communication signal into even and odd samples. The even and odd samples are correlated with a primary synchronization code of the communication signal and complex values of the even and odd samples are generated. Signal strength values for the even and odd samples are approximated and the approximate signal strength values within a frame of the communication signal are accumulated. A highest accumulated signal strength value is assigned as an index value.
    Type: Application
    Filed: October 6, 2008
    Publication date: February 5, 2009
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Alpaslan Demir, Donald M. Grieco
  • Publication number: 20080310374
    Abstract: A wireless transmit receive unit (WTRU) provides facilitation of cell search. In one embodiment, received samples are split into a plurality of sample sets for processing. Each of the sets is processed and an accumulated result is divided by an estimated noise value. In another embodiment, a code correlator correlates the received signal with a primary synchronization code and an auxiliary code correlator having a same length as the code correlator correlates the received signal with a code having a low cross correlation with the primary synchronization code. In another embodiment, a division of an accumulated result with a noise estimate is performed using indexes of the most significant bits.
    Type: Application
    Filed: August 13, 2008
    Publication date: December 18, 2008
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Philip J. Pietraski, Alpaslan Demir, Donald M. Grieco
  • Publication number: 20080298529
    Abstract: A User Equipment (UE) receives and samples communication signals, where the communication signals have a time frame format, a transmission chip rate and a synchronization code associated with a time slot that includes a midamble that indicates a modulation of the synchronization code where a specified modulation of received synchronization codes identifies the timing for a timeslot in which data is to be received. The UE preferably includes a synchronization code determination circuit, a midamble determination circuit, and a phase modulation sequence detection circuit operatively associated with the midamble determination circuit. The UE can be configured for use with the low chip rate option of the Third Generation Partnership Project (3GPP) Universal Mobile Telecommunication System (UMTS) standards that employ a predefined set of downlink SYNC codes that point to midambles which indicate SYNC code modulation sequence to enables reading of data in a subsequent Broadcast Channel (BCH) message.
    Type: Application
    Filed: July 21, 2008
    Publication date: December 4, 2008
    Applicant: INTERDIGITAL TECHNOLOGY CORPORATION
    Inventors: Alpaslan Demir, Fatih M. Ozluturk
  • Patent number: 7460614
    Abstract: A method and system for determining amplitude and phase compensation values used to adjust the amplitude and phase characteristics of real and imaginary signal components of complex signals processed by an analog radio transmitter. The compensation values may be determined in response to detecting a significant temperature change in the transmitter. Corresponding amplitude and phase adjustment signals having levels that correspond to the compensation values are provided to respective amplitude and phase imbalance compensation modules to adjust the amplitude and phase characteristics of at least one of the real and imaginary signal components.
    Type: Grant
    Filed: December 18, 2003
    Date of Patent: December 2, 2008
    Assignee: InterDigital Technology Corporation
    Inventors: Alpaslan Demir, Leonid Kazakevich, Kenneth P. Kearney