Picture of Ori Shental

Ori Shental

Crawford Hill, NJ, USA
Member of Technical Staff and Research Scientist

Education

 

UC San Diego Posdtoctoral Researcher, Center for Magnetic Recording Research (CMRR), 2006 - 2008
Bar-Ilan University
Postdoctoral Fellow, Physics Department, 2006
Tel Aviv University
Doctor of Philosophy (Ph.D.), Electrical Engineering-Systems Deptarment, 2003 - 2006
Tel Aviv University
Bachelor of Science (B.Sc.), Electrical Engineering and Electronics, 1992 - 1996

 

Biography

Happily married to Nurit, a proud father to Libi, Aya and Gur. A frustrated fan of Hapoel Tel-Aviv.

I'm especially interested in the utilization of powerful solution methods from a variety of well-established scientific disciplines, like probabilistic inference in graphical models, machine learning, convex optimization and statistical mechanics into problems in quite diverse aspects of information processing, such as information theory, communications, error-correcting codes, storage and signal processing.

Always happy to connect with interesting people, hearing good ideas, challenging problems and exciting opportunities... so please don’t hesitate!

 

 

Research Interests

  • Coding Theory
  • Communications Paradigms
  • Graph Theory
  • IoT/M2M
  • Mathematics of Networks
  • Modulation & Multiplexing
  • Network Machine Learning

Honors and Awards

Award for Summer Internship
Institute for Telecommunications Research (ITR), University of South Australia, Adelaide, Australia
2003
Award for Multidisciplinary Research
Advanced Communication Center, Tel Aviv University (acc.tau.ac.il)
2005
Best Journal Paper Prize
Yitzhak and Chaya Weinstein Research Institute for Signal Processing, Tel Aviv University
2006
Prize for Outstanding Graduate Student Research
Advanced Communication Center, Tel Aviv University (acc.tau.ac.il)
2007
Best Paper Award in the area of Signal Processing and Coding for Data Storage
IEEE Communications Society
2008 


Selected Articles and Publications

 

Capacity of complexity-constrained noise-free CDMA
IEEE Communication Letters, vol. 10, pp. 10-12 January 2006
Authors: Ori Shental, Ido Kanter, Anthony J. Weiss
An interference-limited noise-free CDMA downlink channel operating under a complexity constraint on the
receiver is introduced. According to this paradigm, detected bits, obtained by performing hard decisions
directly on the channel's matched filter output, must be the same as the transmitted binary inputs. This
channel setting, allowing the use of the simplest receiver scheme, seems to be worthless, making reliable
communication at any rate impossible. We prove, by adopting statistical mechanics notion, that in the large-
system limit such a complexity-constrained CDMA channel gives rise to a non-trivial Shannon-theoretic
capacity, rigorously analyzed and corroborated using finite-size channel simulations.
Parallel vs. sequential belief propagation decoding of LDPC codes over GF(q) and Markov sources
," Physica A: Statistical Mechanics and its Applications, vol. 378, issue 2, pp. 329-335 May 2007
Authors: Ori Shental, Nadav Yacov, Hadar Efraim, Haggai Kfir, Ido Kanter
A sequential updating scheme (SUS) for belief propagation (BP) decoding of LDPC codes over Galois
fields, GF(q)GF(q), and correlated Markov sources is proposed and compared with the standard parallel
updating scheme (PUS). A thorough experimental study of various transmission settings indicates that
the convergence rate, in iterations, of the BP algorithm for the SUS is about one half of that for the PUS,
independent of the finite field size q . Moreover, this 12 factor appears regardless of the correlations of
the source and the channel's noise model, while the error correction performance remains unchanged.
These results may imply on the ‘universality’ of the one half convergence speed-up of SUS decoding. A
comparison to the dynamics of physical spin systems is also addressed.
Information and multiaccess interference in a complexity-constrained vector channel
Journal of Physics A: Mathematical and Theoretical, vol. 40, issue 20, pp. 5241-5260 May 2007
Authors: Ori Shental, Rodrigo de Miguel
A noisy vector channel operating under a strict complexity constraint at the receiver is introduced. According
to this constraint, detected bits, obtained by performing hard decisions directly on the channel's matched
filter output, must be the same as the transmitted binary inputs. An asymptotic analysis is carried out using
mathematical tools imported from the study of neural networks, and it is shown that, under a bounded noise
assumption, such complexity-constrained channel exhibits a non-trivial Shannon-theoretic capacity. It is
found that performance relies on rigorous interference-based multiuser cooperation at the transmitter and that
this cooperation is best served when all transmitters use the same amplitude.
Improved detection in CDMA for biased sources
Journal of Physics A: Mathematical and Theoretical, vol. 40, issue 33, pp. 9977-9985 August 2008
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter, David Saad
We consider the detection of biased information sources in the ubiquitous code-division multiple-access
(CDMA) scheme. We propose a simple modification to both the popular single-user matched-filter detector
and a recently introduced near-optimal message-passing-based multiuser detector. This modification allows
for detecting modulated biased sources directly with no need for source coding. Analytical results and
simulations with excellent agreement are provided, demonstrating substantial improvement in bit error rate
in comparison with the unmodified detectors and the alternative of source compression. The robustness of
error-performance improvement is shown under practical model settings, including bias estimation mismatch
and finite-length spreading codes.
Discrete-input two-dimensional Gaussian channels with memory: Estimation and information rates via
graphical models and statistical mechanics
IEEE Transactions on Information Theory, vol. 54, no. 4, pp. 1500-1513 April 2008
Authors: Ori Shental, , Shlomo Shamai (Shitz), Ido Kanter, Anthony J. Weiss, Yair Weiss
Discrete-input two-dimensional (2D) Gaussian channels with memory represent an important class of
systems, which appears extensively in communications and storage. In spite of their widespread use, the
workings of 2D channels are still very much unknown. In this work, we try to explore their properties from
the perspective of estimation theory and information theory. At the heart of our approach is a mapping of
a 2D channel to an undirected graphical model, and inferring its a posteriori probabilities (APPs) using
generalized belief propagation (GBP). The derived probabilities are shown to be practically accurate, thus
enabling optimal maximum a posteriori (MAP) estimation of the transmitted symbols. Also, the Shannontheoretic information rates are deduced either via the vector-wise Shannon-McMillan-Breiman (SMB)
theorem, or via the recently derived symbol-wise Guo-Shamai-Verdu (GSV) theorem. Our approach is also
described from the perspective of statistical mechanics, as the graphical model and inference algorithm
have their analogues in physics. Our experimental study, based on common channel settings taken from
cellular networks and magnetic recording devices, demonstrates that under nontrivial memory conditions,
the performance of this fully tractable GBP estimator is almost identical to the performance of the optimal
MAP estimator. It also enables a practically accurate simulation-based estimate of the information rate.
Rationalization of this excellent performance of GBP in the 2-D Gaussian channel setting is addressed.
Can quantization improve error performance in CDMA?
Journal of Physics A: Mathematical and Theoretical, vol. 41, issue 36, pp. 365004 September 2008
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter
A K-user direct-sequence spread-spectrum code-division multiple-access (CDMA) system with (q log2K)-
bit baseband signal quantization at the demodulator is considered. It is shown that additionally quantizing
the K + 1 level output signal of the CDMA modulator into q bits improves significantly the average biterror performance in a non-negligible regime of noise variance, #2, and user load, #, under various system
settings, like additive white Gaussian noise (AWGN), Rayleigh fading, single-user detection, multi-user
detection, random and orthogonal spreading codes. For the case of single-user detection in random spreading
AWGN-CDMA, this regime is identified explicitly as , where #(q) is a certain pre-factor depending on q, and
the associated BER improvement is derived analytically for q = 1, 2. For the other examined system settings,
computer simulations are provided, corroborating this interesting behavior.
Thermodynamic derivation of the mutual information for discrete symmetric channels
Journal of Physics A: Mathematical and Theoretical, vol. 41, issue 40, pp. 402002 October 2008
Authors: Ori Shental, Ido Kanter, Hadar Efraim, Nadav Yacov
The mutual information for the binary symmetric channel as well as for the discrete symmetric channel
consisting of 4-input/output (I/O) symbols is explicitly calculated using the generalized second law of
thermodynamics which was recently proposed by the first two authors. For equiprobable I/O the mutual
information of the examined channels has a very simple thermodynamic form as a function of the internal
energy of the channel. We prove that this simple form of the mutual information governs the class of discrete
memoryless symmetric communication channels with equiprobable I/O symbols.
Shannon meets Carnot: Generalized second thermodynamic law
Euro-Physics Letters (EPL), vol. 85, pp. 10006 January 2009
Authors: Ori Shental, Ido Kanter
The classical thermodynamic laws fail to capture the behavior of systems with the energy Hamiltonian being
an explicit function of the temperature. Such Hamiltonian arises, for example, in modeling information
processing systems, like communication channels, as thermal systems. Here we generalize the second
thermodynamic law to encompass systems with temperature-dependent energy levels, , where denotes
averaging over the Boltzmann distribution and reveal a new definition to the basic notion of temperature.
Furthermore, it is shown that the principles of the traditional thermodynamic framework are maintained, e.g.,
two systems in equilibrium have the same generalized temperature and heat always flows from high to low
generalized temperature. This generalization enables to express, for instance, the mutual information of the
Gaussian channel as a consequence of the laws of nature —the laws of thermodynamics.
An efficient CDMA decoder for correlated information sources
Journal of Statistical Mechanics: Theory and Experiment, P07039 July 2009
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter
We consider the detection of correlated information sources in the ubiquitous code-division multiple-access
(CDMA) scheme. We propose a message-passing based scheme for detecting correlated sources directly,
with no need for source coding. The detection is done simultaneously over a block of transmitted binary
symbols (word). Simulation results are provided, demonstrating a substantial improvement in bit error rate
in comparison with the unmodified detector and the alternative of source compression. The robustness of the
error-performance improvement is shown under practical model settings, including wrong estimation of the
generating Markov transition matrix and finite-length spreading codes.
Mutual information via thermodynamics: Three different approaches
Journal of Statistical Mechanics: Theory and Experiment January 2010
Authors: Ori Shental, Yitzhak (Tzahi) Peleg, Hadar Efraim, Ido Kanter
Three different approaches for deriving mutual information via thermodynamics are presented, where the
temperature-dependent energy is given by (a) , (b) or (c) . All approaches require the extension of the
traditional physical framework and the modification of the second law of thermodynamics. A realization
of a physical system with an effective temperature-dependent Hamiltonian is discussed and followed by a
suggestion of a physical information–heat engine.
Statistical-mechanics approach to wide-band digital communication
Physics Review E December 2010
Authors: Ori Shental, Hadar Efraim, Yitzhak (Tzahi) Peleg, Ido Kanter, Yoshiyuki Kabashima
The emerging popular scheme of fourth generation wireless communication, orthogonal frequency-division
multiplexing, is mapped onto a variant of a random field Ising Hamiltonian and results in an efficient
physical intercarrier interference (ICI) cancellation decoding scheme. This scheme is based on Monte Carlo
(MC) dynamics at zero temperature as well as at the Nishimori temperature and demonstrates improved bit
error rate (BER) and robust convergence time compared to the state of the art ICI cancellation decoding
scheme. An optimal BER performance is achieved with MC dynamics at the Nishimori temperature but
with a substantial computational cost overhead. The suggested ICI cancellation scheme also supports the
transmission of biased signals.
Generalized belief propagation receiver for near-optimal detection of two-dimensional channels with
memory
Proc. 2004 IEEE Information Theory Workshop (ITW), San Antonio, Texas, USA October 2004
Authors: Ori Shental, , Anthony J. Weiss, Yair Weiss
On the achievable information rates of two-dimensional channels with memory
Proc. 2005 IEEE Int. Symp. on Inform. Theory (ISIT), Adelaide, Australia September 2005
Authors: Ori Shental, , Shlomo Shamai (Shitz)
Optimum asymptotic multiuser efficiency of pseudo-orthogonal randomly spread CDMA
Proc. WIC 27th Symposium on Information Theory in the Benelux (SITB), Noordwijk, The Netherlands June
2006
Authors: Ori Shental, Ido Kanter
Outsourcing the complexity of detection in MIMO channels
Proc. IEEE Information Theory Workshop (ITW), Chengdu, China October 2006
Authors: Ori Shental, Rodrigo de Miguel, Ido Kanter, Ralf R. Muller
Linear detection via belief propagation
Proc. 45th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL,
USA September 2007
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev
Gaussian belief propagation solver for systems of linear equations
Proc. 2008 IEEE Int. Symp. on Inform. Theory (ISIT), Toronto, Canada July 2008
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev
Gaussian belief propagation based multiuser detection
Proc. 2008 IEEE Int. Symp. on Inform. Theory (ISIT), Toronto, Canada July 2008
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev
Dual transceiver quantization can improve error performance in CDMA
Proc. 10th International Symposium on Spread Spectrum Techniques and Applications (ISSSTA) August 2008
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter
Polynomial linear programming with Gaussian belief
Proc. 46th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL,
USA September 2008
Authors: Ori Shental, Danny Bickson, Danny Dolev
Distributed Kalman filter via Gaussian belief propagation
Proc. 46th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL,
USA September 2008
Authors: Ori Shental, Danny Bickson, Danny Dolev
The second law of thermodynamics for communication channels
Proc. IEEE 25-th Convention of Electrical and Electronics Engineers in Israel, Eilat, Israel December 2008
Authors: Ori Shental, Ido Kanter
Compressed sensing channel estimation in OFDM with applications to mobile TV
Proc. Qualcomm Technology Forum (QTECH), San Diego, CA, USA May 2009
Authors: Ori Shental, Alecsander Eitan
Sparse representation of white Gaussian noise with application to L0-norm decoding in noisy compressed
sensing
Proc. Qualcomm Technology Forum (QTECH), San Diego, CA, USA, June 2011 June 2011
Authors: Ori Shental
Generalized belief propagation receiver for near-optimal detection of two-dimensional channels with
memory
Optimization and Inference in Machine Learning and Physics Workshop (PASCAL), Lavin,
Switzerland January 2005
Authors: Ori Shental, , Anthony J. Weiss, Yair Weiss
Comments on why generalized BP serves so remarkably in 2-D channels
Proc. Information Theory and Applications (ITA) Workshop, San Diego, CA, USA January 2007
Authors: Ori Shental, , Shlomo Shamai (Shitz), Ido Kanter, Anthony J. Weiss, Yair Weiss
A message-passing solver for linear systems
Proc. Information Theory and Applications (ITA) Workshop, San Diego, CA, USA January 2008
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dole
system limit such a complexity-constrained CDMA channel gives rise to a non-trivial Shannon-theoretic
capacity, rigorously analyzed and corroborated using finite-size channel simulations.
Parallel vs. sequential belief propagation decoding of LDPC codes over GF(q) and Markov sources
," Physica A: Statistical Mechanics and its Applications, vol. 378, issue 2, pp. 329-335 May 2007
Authors: Ori Shental, Nadav Yacov, Hadar Efraim, Haggai Kfir, Ido Kanter
A sequential updating scheme (SUS) for belief propagation (BP) decoding of LDPC codes over Galois
fields, GF(q)GF(q), and correlated Markov sources is proposed and compared with the standard parallel
updating scheme (PUS). A thorough experimental study of various transmission settings indicates that
the convergence rate, in iterations, of the BP algorithm for the SUS is about one half of that for the PUS,
independent of the finite field size q . Moreover, this 12 factor appears regardless of the correlations of
the source and the channel's noise model, while the error correction performance remains unchanged.
These results may imply on the ‘universality’ of the one half convergence speed-up of SUS decoding. A
comparison to the dynamics of physical spin systems is also addressed.
Information and multiaccess interference in a complexity-constrained vector channel
Journal of Physics A: Mathematical and Theoretical, vol. 40, issue 20, pp. 5241-5260 May 2007
Authors: Ori Shental, Rodrigo de Miguel
A noisy vector channel operating under a strict complexity constraint at the receiver is introduced. According
to this constraint, detected bits, obtained by performing hard decisions directly on the channel's matched
filter output, must be the same as the transmitted binary inputs. An asymptotic analysis is carried out using
mathematical tools imported from the study of neural networks, and it is shown that, under a bounded noise
assumption, such complexity-constrained channel exhibits a non-trivial Shannon-theoretic capacity. It is
found that performance relies on rigorous interference-based multiuser cooperation at the transmitter and that
this cooperation is best served when all transmitters use the same amplitude.
Improved detection in CDMA for biased sources
Journal of Physics A: Mathematical and Theoretical, vol. 40, issue 33, pp. 9977-9985 August 2008
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter, David Saad
We consider the detection of biased information sources in the ubiquitous code-division multiple-access
(CDMA) scheme. We propose a simple modification to both the popular single-user matched-filter detector
and a recently introduced near-optimal message-passing-based multiuser detector. This modification allows
for detecting modulated biased sources directly with no need for source coding. Analytical results and
simulations with excellent agreement are provided, demonstrating substantial improvement in bit error rate
in comparison with the unmodified detectors and the alternative of source compression. The robustness of
error-performance improvement is shown under practical model settings, including bias estimation mismatch
and finite-length spreading codes.
Discrete-input two-dimensional Gaussian channels with memory: Estimation and information rates via
graphical models and statistical mechanics
IEEE Transactions on Information Theory, vol. 54, no. 4, pp. 1500-1513 April 2008
Authors: Ori Shental, , Shlomo Shamai (Shitz), Ido Kanter, Anthony J. Weiss, Yair Weiss
Discrete-input two-dimensional (2D) Gaussian channels with memory represent an important class of
systems, which appears extensively in communications and storage. In spite of their widespread use, the
workings of 2D channels are still very much unknown. In this work, we try to explore their properties from
the perspective of estimation theory and information theory. At the heart of our approach is a mapping of
a 2D channel to an undirected graphical model, and inferring its a posteriori probabilities (APPs) using
generalized belief propagation (GBP). The derived probabilities are shown to be practically accurate, thus
enabling optimal maximum a posteriori (MAP) estimation of the transmitted symbols. Also, the Shannontheoretic information rates are deduced either via the vector-wise Shannon-McMillan-Breiman (SMB)
theorem, or via the recently derived symbol-wise Guo-Shamai-Verdu (GSV) theorem. Our approach is also
described from the perspective of statistical mechanics, as the graphical model and inference algorithm
have their analogues in physics. Our experimental study, based on common channel settings taken from
cellular networks and magnetic recording devices, demonstrates that under nontrivial memory conditions,
the performance of this fully tractable GBP estimator is almost identical to the performance of the optimal
MAP estimator. It also enables a practically accurate simulation-based estimate of the information rate.
Rationalization of this excellent performance of GBP in the 2-D Gaussian channel setting is addressed.
Can quantization improve error performance in CDMA?
Journal of Physics A: Mathematical and Theoretical, vol. 41, issue 36, pp. 365004 September 2008
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter
A K-user direct-sequence spread-spectrum code-division multiple-access (CDMA) system with (q log2K)-
bit baseband signal quantization at the demodulator is considered. It is shown that additionally quantizing
the K + 1 level output signal of the CDMA modulator into q bits improves significantly the average biterror performance in a non-negligible regime of noise variance, #2, and user load, #, under various system
settings, like additive white Gaussian noise (AWGN), Rayleigh fading, single-user detection, multi-user
detection, random and orthogonal spreading codes. For the case of single-user detection in random spreading
AWGN-CDMA, this regime is identified explicitly as , where #(q) is a certain pre-factor depending on q, and
the associated BER improvement is derived analytically for q = 1, 2. For the other examined system settings,
computer simulations are provided, corroborating this interesting behavior.
Thermodynamic derivation of the mutual information for discrete symmetric channels
Journal of Physics A: Mathematical and Theoretical, vol. 41, issue 40, pp. 402002 October 2008
Authors: Ori Shental, Ido Kanter, Hadar Efraim, Nadav Yacov
The mutual information for the binary symmetric channel as well as for the discrete symmetric channel
consisting of 4-input/output (I/O) symbols is explicitly calculated using the generalized second law of
thermodynamics which was recently proposed by the first two authors. For equiprobable I/O the mutual
information of the examined channels has a very simple thermodynamic form as a function of the internal
energy of the channel. We prove that this simple form of the mutual information governs the class of discrete
memoryless symmetric communication channels with equiprobable I/O symbols.
Shannon meets Carnot: Generalized second thermodynamic law
Euro-Physics Letters (EPL), vol. 85, pp. 10006 January 2009
Authors: Ori Shental, Ido Kanter
The classical thermodynamic laws fail to capture the behavior of systems with the energy Hamiltonian being
an explicit function of the temperature. Such Hamiltonian arises, for example, in modeling information
processing systems, like communication channels, as thermal systems. Here we generalize the second
thermodynamic law to encompass systems with temperature-dependent energy levels, , where denotes
averaging over the Boltzmann distribution and reveal a new definition to the basic notion of temperature.
Furthermore, it is shown that the principles of the traditional thermodynamic framework are maintained, e.g.,
two systems in equilibrium have the same generalized temperature and heat always flows from high to low
generalized temperature. This generalization enables to express, for instance, the mutual information of the
Gaussian channel as a consequence of the laws of nature —the laws of thermodynamics.
An efficient CDMA decoder for correlated information sources
Journal of Statistical Mechanics: Theory and Experiment, P07039 July 2009
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter
We consider the detection of correlated information sources in the ubiquitous code-division multiple-access
(CDMA) scheme. We propose a message-passing based scheme for detecting correlated sources directly,
with no need for source coding. The detection is done simultaneously over a block of transmitted binary
symbols (word). Simulation results are provided, demonstrating a substantial improvement in bit error rate
in comparison with the unmodified detector and the alternative of source compression. The robustness of the
error-performance improvement is shown under practical model settings, including wrong estimation of the
generating Markov transition matrix and finite-length spreading codes.
Mutual information via thermodynamics: Three different approaches
Journal of Statistical Mechanics: Theory and Experiment January 2010
Authors: Ori Shental, Yitzhak (Tzahi) Peleg, Hadar Efraim, Ido Kanter
Three different approaches for deriving mutual information via thermodynamics are presented, where the
temperature-dependent energy is given by (a) , (b) or (c) . All approaches require the extension of the
traditional physical framework and the modification of the second law of thermodynamics. A realization
of a physical system with an effective temperature-dependent Hamiltonian is discussed and followed by a
suggestion of a physical information–heat engine.
Statistical-mechanics approach to wide-band digital communication
Physics Review E December 2010
Authors: Ori Shental, Hadar Efraim, Yitzhak (Tzahi) Peleg, Ido Kanter, Yoshiyuki Kabashima
The emerging popular scheme of fourth generation wireless communication, orthogonal frequency-division
multiplexing, is mapped onto a variant of a random field Ising Hamiltonian and results in an efficient
physical intercarrier interference (ICI) cancellation decoding scheme. This scheme is based on Monte Carlo
(MC) dynamics at zero temperature as well as at the Nishimori temperature and demonstrates improved bit
error rate (BER) and robust convergence time compared to the state of the art ICI cancellation decoding
scheme. An optimal BER performance is achieved with MC dynamics at the Nishimori temperature but
with a substantial computational cost overhead. The suggested ICI cancellation scheme also supports the
transmission of biased signals.
Generalized belief propagation receiver for near-optimal detection of two-dimensional channels with
memory
Proc. 2004 IEEE Information Theory Workshop (ITW), San Antonio, Texas, USA October 2004
Authors: Ori Shental, , Anthony J. Weiss, Yair Weiss
On the achievable information rates of two-dimensional channels with memory
Proc. 2005 IEEE Int. Symp. on Inform. Theory (ISIT), Adelaide, Australia September 2005
Authors: Ori Shental, , Shlomo Shamai (Shitz)
Optimum asymptotic multiuser efficiency of pseudo-orthogonal randomly spread CDMA
Proc. WIC 27th Symposium on Information Theory in the Benelux (SITB), Noordwijk, The Netherlands June
2006
Authors: Ori Shental, Ido Kanter
Outsourcing the complexity of detection in MIMO channels
Proc. IEEE Information Theory Workshop (ITW), Chengdu, China October 2006
Authors: Ori Shental, Rodrigo de Miguel, Ido Kanter, Ralf R. Muller
Linear detection via belief propagation
Proc. 45th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL,
USA September 2007
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev
Gaussian belief propagation solver for systems of linear equations
Proc. 2008 IEEE Int. Symp. on Inform. Theory (ISIT), Toronto, Canada July 2008
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev
Gaussian belief propagation based multiuser detection
Proc. 2008 IEEE Int. Symp. on Inform. Theory (ISIT), Toronto, Canada July 2008
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev
Dual transceiver quantization can improve error performance in CDMA
Proc. 10th International Symposium on Spread Spectrum Techniques and Applications (ISSSTA) August 2008
Authors: Ori Shental, Hadar Efraim, Nadav Yacov, Ido Kanter
Polynomial linear programming with Gaussian belief
Proc. 46th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL,
USA September 2008
Authors: Ori Shental, Danny Bickson, Danny Dolev
Distributed Kalman filter via Gaussian belief propagation
Proc. 46th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL,
USA September 2008
Authors: Ori Shental, Danny Bickson, Danny Dolev
The second law of thermodynamics for communication channels
Proc. IEEE 25-th Convention of Electrical and Electronics Engineers in Israel, Eilat, Israel December 2008
Authors: Ori Shental, Ido Kanter
Compressed sensing channel estimation in OFDM with applications to mobile TV
Proc. Qualcomm Technology Forum (QTECH), San Diego, CA, USA May 2009
Authors: Ori Shental, Alecsander Eitan
Sparse representation of white Gaussian noise with application to L0-norm decoding in noisy compressed
sensing
Proc. Qualcomm Technology Forum (QTECH), San Diego, CA, USA, June 2011 June 2011
Authors: Ori Shental
Generalized belief propagation receiver for near-optimal detection of two-dimensional channels with
memory
Optimization and Inference in Machine Learning and Physics Workshop (PASCAL), Lavin,
Switzerland January 2005
Authors: Ori Shental, , Anthony J. Weiss, Yair Weiss
Comments on why generalized BP serves so remarkably in 2-D channels
Proc. Information Theory and Applications (ITA) Workshop, San Diego, CA, USA January 2007
Authors: Ori Shental, , Shlomo Shamai (Shitz), Ido Kanter, Anthony J. Weiss, Yair Weiss
A message-passing solver for linear systems
Proc. Information Theory and Applications (ITA) Workshop, San Diego, CA, USA January 2008
Authors: Ori Shental, Danny Bickson, Paul H. Siegel, Jack K. Wolf, Danny Dolev 

Patents

 

Method and system for linear processing of an input using Gaussian belief propagationUnited States Patent US8139656 B2 Issued March 20, 2012
Inventors: Ori Shental, Danny Dolev, Danny Bickson
Methods and systems for processing an input. An input vector y is received that represents a noisy
observation of Ax, where A is a data matrix and x is a data vector of unknown variables. Data vector x is
recovered from the received input vector y via an iterative method. The recovering comprises determining an
inference of a vector of marginal means over a graph G, where the graph G is of a joint Gaussian probability
density function p(x) associated with noise in the received input vector y.
Apparatus and method for compressive sensing tap identification for channel estimation
United States Patent US8644402 B2 Issued February 4, 2014
Inventors: Ori Shental, Farrokh Abrishamkar, Ni-Chun Wang, Yingqun Yu
An apparatus and method for compressive sensing tap identification for channel estimation comprising
identifying a set of significant taps in the time domain; representing a time-flat channel response using
a Taylor series expansion with the set of significant taps; converting the time-flat channel response to a
vectorized channel response; transforming the vectorized channel response to a compressive sensing (CS)
polynomial frequency response; aggregating the CS polynomial frequency response into a stacked frequency
response; converting the stacked frequency response into a measured pilot frequency response; estimating
a channel parameter vector based on the measured pilot frequency response; and generating a reconstructed
channel response from the channel parameter vector.
Apparatus and method for channel estimation using compressive sensing based on Taylor series
expansion

United States Patent US8582674 B2 Issued November 12, 2013
Inventors: Ori Shental, Yingqun Yu, Farrokh Abrishamkar, Ni-Chun Wang
An apparatus and method for channel estimation comprising determining a channel impulse response using
a Taylor series expansion with a plurality of Taylor series coefficients; determining a channel frequency
response based on the channel impulse response; collecting the channel frequency response over a plurality
of symbols to obtain a composite channel frequency response; generating a sensing matrix based on the
Taylor series expansion; and determining the plurality of Taylor series coefficients based on the composite
channel frequency response and the sensing matrix using compressive sensing channel estimation.
Apparatus and method for channel estimation using compressive sensing
United States Patent US 8665971 B2 Issued March 4, 2014
Inventors: Ori Shental, Farrokh Abrishamkar, Ni-Chun Wang, Yingqun Yu
An apparatus and method for channel estimation comprising obtaining a response matrix G(l) using Q
quantity pilots; constructing a sensing matrix Wsensing based on K quantity tones, L quantity symbols and
P quantity multipaths; and using compressive sensing channel estimation to determine an equivalent channel
matrix Gp(i) based on the response matrix G(l) and the sensing matrix Wsensing.
Page4
Method and apparatus for ATSC signal processing
United States Patent 8,699,641 Issued April 15, 2014
Inventors: Ori Shental, Alecsander Eitan
Embodiment methods and apparatus enable ATSC receiver devices to receive and process ATSC-M/H
training sequences in order to improve the reception and decoding of an ATSC service. A processor within
the ATSC receiver device may be configured to receive training sequences 1 and 2 of the ATSC-M/H signal.
In an embodiment, the ATSC-M/H training sequence 2 may be received by correlating symbols of the
two halves of the training sequence 2. If the result of correlating the symbols is greater than or equal to a
threshold, the ATSC-M/H training sequence 2 may be received by the ATSC receiver and a counter for the
training sequence 1 may start. The ATSC receiver may correlate two consecutive training sequences 1 to
perform fine residual frequency error estimation.
Compressed sensing channel estimation in OFDM communication systems
United States Patent US8774294 B2 Issued July 8, 2014
Inventors: Ori Shental, Alecsander Eitan
Methods and devices for receiving Orthogonal Frequency Domain Multiplexed (OFDM) wireless signals
employ compressed sensing-based estimation techniques, exploiting the common sparseness of the wireless
channel, to achieve signal reception in the presence of significant Doppler spread. When implemented for
an ISDB-T mobile TV standard signal, the compressed sensing channel estimation algorithm enables data
reception in Doppler spread conditions beyond the capabilities of conventional channel estimation methods
Efficient compressed sensing channel estimation for single-carrier communication systems
United States Patent 8942321 Issued January 27, 2015
Inventors: Ori Shental, Alecsander Eitan
Methods and devices for receiving wireless signals employ compressed sensing-based estimation techniques
to receive single-carrier transmissions, exploiting the common sparseness of the wireless channel, enabling
signal reception in the presence of significant Delay and Doppler spreads. When implemented for an ATSC
or ATSC-M/H mobile TV standard signal, the compressed sensing channel estimation algorithm enables data
reception in Delay and Doppler spread conditions beyond the capabilities of conventional channel estimation
methods.