Patents by Inventor Georgios B. Giannakis

Georgios B. Giannakis 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: 9863985
    Abstract: A semidefinite (SDR) programming formulation for state estimation (SE) of nonlinear AC power systems is described. The techniques make use of convex semidefinite relaxation of the original problem to render the process efficiently solvable. In addition, robust techniques are described that are resilient to outlying measurements and/or adversarial cyber-attacks. Further, techniques for SDR-based SE are described in which local control areas solve the centralized SDP-based SE problem in a distributed fashion.
    Type: Grant
    Filed: April 12, 2013
    Date of Patent: January 9, 2018
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Hao Zhu
  • Patent number: 9614633
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Grant
    Filed: May 24, 2016
    Date of Patent: April 4, 2017
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20170019160
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Application
    Filed: May 24, 2016
    Publication date: January 19, 2017
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20160269138
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Application
    Filed: May 24, 2016
    Publication date: September 15, 2016
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20160259314
    Abstract: Decentralized methods for computing optimal real and reactive power setpoints for residential photovoltaic (PV) inverters are described. Optimal power flow techniques are described that select which inverters will provide ancillary services and compute their optimal real and reactive power setpoints according to specified performance criteria and economic objectives.
    Type: Application
    Filed: March 4, 2016
    Publication date: September 8, 2016
    Inventors: Sairaj Dhople, Georgios B. Giannakis, Emiliano Dall'Anese
  • Patent number: 9374143
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: June 21, 2016
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Patent number: 9363679
    Abstract: This disclosure describes techniques for constructing power spectral density (PSD) maps representative of the distribution of radio frequency (RF) power as a function of both frequency and space (geographic location). For example, the disclosure describes techniques for construction PSD maps using robust basis pursuit forms of signal expansion.
    Type: Grant
    Filed: June 18, 2013
    Date of Patent: June 7, 2016
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Emiliano Dall'Anese, Juan Andrés Bazerque, Hao Zhu, Gonzalo Mateos
  • Patent number: 9191831
    Abstract: This disclosure describes techniques for constructing power spectral density (PSD) maps representative of the distribution of radio frequency (RF) power as a function of both frequency and space (geographic location). For example, the disclosure describes techniques for construction PSD maps using non-parametric basis pursuit form of signal expansion.
    Type: Grant
    Filed: May 21, 2013
    Date of Patent: November 17, 2015
    Assignees: Regents of the University of Minnesota, NATIONAL SCIENCE FOUNDATION
    Inventors: Georgios B. Giannakis, Juan Andres Bazerque, Gonzalo Mateos
  • Publication number: 20150288430
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Application
    Filed: May 28, 2014
    Publication date: October 8, 2015
    Applicant: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20140211644
    Abstract: This disclosure describes techniques for constructing power spectral density (PSD) maps representative of the distribution of radio frequency (RF) power as a function of both frequency and space (geographic location). For example, the disclosure describes techniques for construction PSD maps using robust basis pursuit forms of signal expansion.
    Type: Application
    Filed: June 18, 2013
    Publication date: July 31, 2014
    Applicant: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Emiliano Dall'Anese, Juan Andrés Bazerque, Hao Zhu, Gonzalo Mateos
  • Patent number: 8774309
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: July 8, 2014
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Patent number: 8718185
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: May 6, 2014
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20130310093
    Abstract: This disclosure describes techniques for constructing power spectral density (PSD) maps representative of the distribution of radio frequency (RF) power as a function of both frequency and space (geographic location). For example, the disclosure describes techniques for construction PSD maps using non-parametric basis pursuit form of signal expansion.
    Type: Application
    Filed: May 21, 2013
    Publication date: November 21, 2013
    Applicant: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Juan Andres Bazerque, Gonzalo Mateos
  • Patent number: 8588317
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Grant
    Filed: November 21, 2011
    Date of Patent: November 19, 2013
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20130304266
    Abstract: A semidefinite (SDR) programming formulation for state estimation (SE) of nonlinear AC power systems is described. The techniques make use of convex semidefinite relaxation of the original problem to render the process efficiently solvable. In addition, robust techniques are described that are resilient to outlying measurements and/or adversarial cyber-attacks. Further, techniques for SDR-based SE are described in which local control areas solve the centralized SDP-based SE problem in a distributed fashion.
    Type: Application
    Filed: April 12, 2013
    Publication date: November 14, 2013
    Inventors: Georgios B. Giannakis, Hao Zhu
  • Publication number: 20120155512
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Application
    Filed: November 21, 2011
    Publication date: June 21, 2012
    Applicant: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Patent number: 8064528
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: November 22, 2011
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Publication number: 20110255572
    Abstract: Techniques are described for carrier frequency offset (CFO) and channel estimation of orthogonal frequency division multiplexing (OFDM) transmissions over multiple-input multiple-output (MIMO) frequency-selective fading channels. A wireless transmitter forms blocks of symbols by inserting training symbols within two or more blocks of information-bearing symbols. The transmitter applies a hopping code to each of the blocks of symbols to insert a null subcarrier at a different position within each of the blocks of symbols, and a modulator outputs a wireless signal in accordance with the blocks of symbols. A receiver receives the wireless signal and estimates the CFO, and outputs a stream of estimated symbols based on the estimated CFO.
    Type: Application
    Filed: May 21, 2004
    Publication date: October 20, 2011
    Inventors: Georgios B. Giannakis, Xiaoli Ma
  • Patent number: 7864880
    Abstract: Techniques are described that provide inter-symbol interference—(ISI) and multi-user interference—(MUI) resilient blind timing synchronization and low complexity demodulation in wireless communication systems. A nonzero mean symbol is transmitted with a predetermined period in a stream of zero mean symbols during a synchronization phase. Only zero mean symbols are transmitted outside of the synchronization phase. Blind or non-data aided synchronization is performed at the receiver while bypassing channel estimation. The techniques enable timing synchronization via energy detection and low-complexity demodulation by matching the received waveform to a synchronized aggregate template (SAT). The SAT is recovered by averaging samples of the received waveform during the synchronization phase.
    Type: Grant
    Filed: October 4, 2005
    Date of Patent: January 4, 2011
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Xiliang Luo
  • Patent number: RE45230
    Abstract: In general, linear complex-field encoding techniques are proposed. For example, transmitter of a wireless communication system includes an encoder and a modulator. The encoder linearly encodes a data stream to produce an encoded data stream. The modulator to produce an output waveform in accordance with the encoded data stream for transmission through a wireless channel. The modulator generates the output waveform as a multicarrier waveform having a set of subcarriers, e.g., an Orthogonal Frequency Division Multiplexing (OFDM) waveform. The encoder linearly encodes the data stream so that the subcarriers carry different linear combinations of information symbols of the data stream.
    Type: Grant
    Filed: April 8, 2013
    Date of Patent: November 4, 2014
    Assignee: Regents of the University of Minnesota
    Inventors: Georgios B. Giannakis, Yan Xin, Zhengdao Wang