By injecting false data through compromised sensors, an adversary can drive the probability of detection in a sensor network-based spatial field surveillance system to arbitrarily low values. As a countermeasure, a small subset of sensors may be secured. Leveraging the theory of Matched Subspace Detection, we propose and evaluate several detectors that add robustness to attacks when such trusted nodes are available. Our results reveal the performance-security tradeoff of these schemes and can be used to determine the number of trusted nodes required for a given performance target.

JF - European Signal Processing Conference (EUSIPCO)
CY - Kos Island, Greece
ER -
TY - CONF
T1 - Design of projection matrices for PRNU compression
T2 - 2017 IEEE Workshop on Information Forensics and Security (WIFS)
Y1 - 2017
A1 - L. Bondi
A1 - Fernando Pérez-González
A1 - P. Bestagini
A1 - S. Tubaro
KW - acquisition time
KW - cameras
KW - computational complexity
KW - data compression
KW - defacto standard
KW - design methodology
KW - digital photo
KW - forensics investigators
KW - image coding
KW - Image forensics
KW - image sensors
KW - image source identification
KW - interpolation
KW - matrix algebra
KW - nearly-flat spectral characteristics
KW - Performance evaluation
KW - photo response nonuniformity
KW - PRNU compression
KW - probability
KW - projection matrices
KW - public image dataset
KW - Signal to noise ratio
KW - silicon sensor imperfections
KW - specific camera sensor
KW - weak multiplicative noise
JF - 2017 IEEE Workshop on Information Forensics and Security (WIFS)
ER -
TY - CONF
T1 - Distributed Precoding Systems in Multi-Gateway Multibeam Satellites
T2 - 35th AIAA International Communications Satellite Systems Conference
Y1 - 2017
A1 - Carlos Mosquera
A1 - R. López-Valcarce
A1 - Tomás Ramírez
KW - precoding
KW - satcom
JF - 35th AIAA International Communications Satellite Systems Conference
CY - Trieste,Italy
ER -
TY - JOUR
T1 - Data Hiding Robust to Mobile Communication Vocoders
JF - IEEE Transactions on Multimedia
Y1 - 2016
A1 - Reza Kazemi
A1 - Fernando Pérez-González
A1 - Mohamed Ali Akhaee
A1 - Fereydoon Behnia
VL - 18
IS - 12
ER -
TY - CONF
T1 - Design of data-injection adversarial attacks against spatial field detectors
T2 - IEEE Workshop on Statistical Signal Processing (SSP)
Y1 - 2016
A1 - R. López-Valcarce
A1 - Daniel Romero
KW - adversarial signal processing
KW - compass
KW - wsn
AB - Data-injection attacks on spatial field detection corrupt a subset of measurements to cause erroneous decisions. We consider a centralized decision scheme exploiting spatial field smoothness to overcome lack of knowledge on system parameters such as noise variance. We obtain closed-form expressions for system performance and investigate strategies for an intruder injecting false data in a fraction of the sensors in order to reduce the probability of detection. The problem of determining the most vulnerable subset of sensors is also analyzed.

JF - IEEE Workshop on Statistical Signal Processing (SSP) CY - Palma de Mallorca, Spain ER - TY - JOUR T1 - Design of pool mixes against profiling attacks in real conditions JF - IEEE/ACM Transactions on Networking Y1 - 2016 A1 - Simon Oya A1 - Fernando Pérez-González A1 - Carmela Troncoso KW - adversarial signal processing KW - compass VL - 24 IS - 6 ER - TY - JOUR T1 - Designing incoherent frames through convex techniques for optimized compressed sensing JF - IEEE Transactions on Signal Processing Y1 - 2016 A1 - Cristian Rusu A1 - Nuria González-Prelcic KW - compass KW - compressed sensing VL - 64 IS - 9 ER - TY - THES T1 - Detection of Image Resampling and Video Encoding Footprints for Forensic Applications Y1 - 2016 A1 - David Vázquez-Padín PB - University of Vigo CY - Vigo ER - TY - CONF T1 - Distributed multivariate regression with unknown noise covariance in the presence of outliers: a minimum description length approach T2 - IEEE Workshop on Statistical Signal Processing (SSP) Y1 - 2016 A1 - R. López-Valcarce A1 - Daniel Romero A1 - Josep Sala A1 - Alba Pagès-Zamora KW - compass KW - wsn AB -We consider the problem of estimating the coefficients in a multivariable linear model by means of a wireless sensor network

which may be affected by anomalous measurements. The noise covariance matrices at the different sensors are assumed

unknown. Treating outlying samples, and their support, as additional nuisance parameters, the Maximum Likelihood

estimate is investigated, with the number of outliers being estimated according to the Minimum Description Length

principle. A distributed implementation based on iterative consensus techniques is then proposed, and it is shown effective

for managing outliers in the data.

JF - IEEE Workshop on Statistical Signal Processing (SSP)
CY - Palma de Mallorca, Spain
ER -
TY - CONF
T1 - Dynamic Privacy-Preserving Genomic Susceptibility Testing
T2 - ACM Workshop on Information Hiding and Multimedia Security
Y1 - 2016
A1 - Mina Namazi
A1 - Juan Ramón Troncoso-Pastoriza
A1 - Fernando Pérez-González
JF - ACM Workshop on Information Hiding and Multimedia Security
ER -
TY - CONF
T1 - Dictionary-free Hybrid Precoders and Combiners for mmWave MIMO Systems
T2 - IEEE Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
Y1 - 2015
A1 - Roi Méndez-Rial
A1 - Cristian Rusu
A1 - Nuria González-Prelcic
A1 - Robert W. Heath Jr.
KW - compass
KW - mmWave
JF - IEEE Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
PB - IEEE
CY - Stockholm, Sweden
ER -
TY - CONF
T1 - Distributed AoA-based Source Positioning in NLOS with Sensor Networks
T2 - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
Y1 - 2015
A1 - Pere Gimenez-Febrer
A1 - Alba Pagès-Zamora
A1 - Silvana Silva Pereira
A1 - R. López-Valcarce
KW - compass
KW - wsn
AB - This paper focuses on the problem of positioning a source using angle-of-arrival measurements taken by a wireless sensor network in which some of the nodes experience non-line-of-sight (NLOS) propagation conditions. In order to mitigate the errors induced by the nodes in NLOS, we derive an algorithm that combines the expectation-maximization algorithm with a weighted least-squares estimation of the source position so that the nodes in NLOS are eventually identified and discarded. Moreover, a distributed version of this algorithm based on a diffusion strategy that iteratively refines the position estimate while driving the network to a consensus is presented.

JF - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
PB - IEEE
CY - Brisbane, Australia
ER -
TY - CONF
T1 - Distributed TLS Estimation under Random Data Faults
T2 - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
Y1 - 2015
A1 - Silvana Silva Pereira
A1 - Alba Pagès-Zamora
A1 - R. López-Valcarce
KW - compass
KW - wsn
AB - This paper addresses the problem of distributed estimation of a parameter vector in the presence of noisy input and output data as well as data faults, performed by a wireless sensor network in which only local interactions among the nodes are allowed. In the presence of unreliable observations, standard estimators become biased and perform poorly in low signal-to-noise ratios. We propose two different distributed approaches based on the Expectation-Maximization algorithm: in the first one the regressors are estimated at each iteration,

whereas the second one does not require explicit regressor estimation. Numerical results show that the proposed methods approach the performance of a clairvoyant scheme with knowledge of the random data faults.

JF - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
PB - IEEE
CY - Brisbane, Australia
ER -
TY - CONF
T1 - Detecting Misreporting Attacks to the Proportional Fair Scheduler
T2 - IEEE Workshop on Information Forensics and Security (WIFS)
Y1 - 2014
A1 - Schmidt, J.F.
A1 - R. López-Valcarce
KW - adversarial signal processing
KW - compass
AB - The Proportional Fair Scheduler (PFS) has become

a popular channel-aware resource allocation method in wireless

networks, as it effectively exploits multiuser diversity while

providing fairness to users. PFS decisions on which mobile station

(MS) to schedule next are based on Channel Quality Indicator

(CQI) values. Since CQI values are reported by the MSs to the

scheduler, network performance can be severely degraded if some

malicious MSs report forged information. Previous approaches to

this security issue are based either on modifying PFS, which may

be undesirable in some contexts, or authenticating CQI reports

by periodic transmission of challenges, which increases overhead.

Instead, we propose to detect misreporting attackers, based on the

time correlation features of the wireless channel. Our approach

does not require scheduler modification, and it does not increase

overhead. Simulation results under realistic settings are provided

to show the effectiveness of the proposed test.

JF - IEEE Workshop on Information Forensics and Security (WIFS)
CY - Atlanta, USA
ER -
TY - CONF
T1 - Dissection of multibeam satellite communications with a large-scale antenna system toolbox
T2 - European Wireless 2014 (EW2014)
Y1 - 2014
A1 - Arnau, Jesus
A1 - Carlos Mosquera
KW - dynacs
KW - large-scale analysis
KW - Massive MIMO
KW - multibeam satellites
KW - Multiuser detection
KW - satcom
AB - Current multibeam satellite systems consist of a very large number of spot beams. In this paper, we analyze them from the large scale MIMO perspective, and establish a comparison with massive MIMO systems. It will be shown that the large number of beams has important operational implications, and that it simplifies the analysis because it allows using asymptotic results. However, it will also be shown that multibeam satellite systems cannot be considered massive MIMO systems.

JF - European Wireless 2014 (EW2014) CY - Barcelona, Spain ER - TY - CONF T1 - Distributed Total Least Squares Estimation over Networks T2 - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) Y1 - 2014 A1 - R. López-Valcarce A1 - Silvana Silva Pereira A1 - Alba Pagès-Zamora KW - dynacs KW - wsn AB -We consider Total Least Squares (TLS) estimation in a network in which each node has access to a subset of equations of an overdetermined linear system. Previous distributed approaches require that the number of equations at each node be larger than the dimension L of the unknown parameter. We present novel distributed TLS estimators which can handle as few as a single equation per node. In the first scheme, the network computes an extended correlation matrix via standard iterative average consensus techniques, and the TLS estimate is extracted afterwards by means of an eigenvalue decomposition (EVD). The second scheme is EVD-free, but requires that a linear system of size L be solved at each iteration by each node. Replacing this step by a single Gauss-Seidel subiteration is shown to be an effective means to reduce computational cost without sacrificing performance.

JF - IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) CY - Florence, Italy ER - TY - CONF T1 - Do dummies pay off? Limits of dummy traffic protection in anonymous communications T2 - Privacy Enhancing Technologies Symposium Y1 - 2014 A1 - Simon Oya A1 - Carmela Troncoso A1 - Fernando Pérez-González KW - anonymous communications KW - compass KW - disclosure attacks KW - dummies JF - Privacy Enhancing Technologies Symposium ER - TY - JOUR T1 - On the design of a novel two-objective harmony search approach for distance- and connectivity-based localization in wireless sensor networks JF - Engineering Applications of Artificial Intelligence Y1 - 2013 A1 - Diana Manjarres A1 - Javier Del Ser A1 - Sergio Gil-Lopez A1 - Massimo Vecchio A1 - Itziar Landa-Torres A1 - Sancho Salcedo-Sanz A1 - R. López-Valcarce KW - dynacs KW - wsn VL - 26 IS - 2 ER - TY - CONF T1 - A Diffusion-based distributed EM algorithm for density estimation in wireless sensor networks T2 - Int. Conf. Acoust., Speech, Signal Process. (ICASSP) Y1 - 2013 A1 - Silvana Silva Pereira A1 - Alba Pagès-Zamora A1 - R. López-Valcarce KW - dynacs KW - wsn AB -Distributed implementations of the Expectation-Maximization

(EM) algorithm reported in the literature have been proposed for

applications to solve specific problems. In general, a primary

requirement to derive a distributed solution is that the

structure of the centralized version enables the computation

involving global information in a distributed fashion. This

paper treats the problem of distributed estimation of Gaussian

densities by means of the EM algorithm in wireless sensor

networks using diffusion strategies, where the information

is gradually diffused across the network for the computation

of the global functions. The low-complexity implementation

presented here is based on a two time scale operation

for information averaging and diffusion. The convergence to

a fixed point of the centralized solution has been studied and

the appealing results motivates our choice for this model. Numerical

examples provided show that the performance of the

distributed EM is, in practice, equal to that of the centralized

scheme.

JF - Int. Conf. Acoust., Speech, Signal Process. (ICASSP)
ER -
TY - JOUR
T1 - A Diffusion-Based EM Algorithm for Distributed Estimation in Unreliable Sensor Networks
JF - IEEE Signal Processing Letters
Y1 - 2013
A1 - Silvana Silva Pereira
A1 - R. López-Valcarce
A1 - Alba Pagès-Zamora
KW - dynacs
KW - wsn
AB - We address the problem of distributed estimation of a parameter from a set of noisy observations collected by a sensor network, assuming that some sensors may be subject to data failures and report only noise. In such scenario, simple schemes such as the Best Linear Unbiased Estimator result in an error floor in moderate and high signal-to-noise ratio (SNR), whereas previously proposed methods based on hard decisions on data failure events degrade as the SNR decreases. Aiming at optimal performance within the whole range of SNRs, we adopt a Maximum Likelihood framework based on the Expectation-Maximization (EM) algorithm. The statistical model and the iterative nature of the EM method allow for a diffusion-based distributed implementation, whereby the information propagation is embedded in the iterative update of the parameters. Numerical examples show that the proposed algorithm practically attains the Cramer–Rao Lower Bound at all SNR values and compares favorably with other approaches.

VL - 20 IS - 6 ER - TY - CONF T1 - Design of universal multicoset sampling patterns for compressed sensing of multiband sparse signals T2 - IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) Y1 - 2012 A1 - M. Elena Domínguez-Jiménez A1 - Nuria González-Prelcic A1 - Gonzalo Vázquez-Vilar A1 - R. López-Valcarce AB -Many problems in digital communications involve wideband radio signals. As the most recent example, the impressive advances in Cognitive Radio systems make even more necessary the development of sampling schemes for wideband radio signals with spectral holes. This is equivalent to considering a sparse multiband signal in the framework of Compressive Sampling theory. Starting from previous results on multicoset sampling and recent advances in compressive sampling, we analyze the matrix involved in the corresponding reconstruction equation and define a new method for the design of universal multicoset codes, that is, codes guaranteeing perfect reconstruction of the sparse multiband signal.

JF - IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) CY - Kyoto (Japan) SN - 978-1-4673-0044-5 ER - TY - CONF T1 - Detection and information theoretic measures for quantifying the distinguishability between multimedia operator chains T2 - IEEE Workshop on Information Forensics and Security Y1 - 2012 A1 - Pedro Comesaña JF - IEEE Workshop on Information Forensics and Security PB - IEEE CY - Tenerife, Spain ER - TY - CONF T1 - Detection of Gaussian signals in unknown time-varying channels T2 - IEEE Statistical Signal Processing Workshop (SSP 2012) Y1 - 2012 A1 - Daniel Romero A1 - Javier Vía A1 - R. López-Valcarce A1 - Ignacio Santamaría KW - cognitive radio KW - dynacs KW - spectrum sensing AB -Detecting the presence of a white Gaussian signal distorted by a noisy time-varying channel is addressed by means of three different detectors. First, the generalized likelihood ratio test (GLRT) is found for the case where the channel has no temporal structure, resulting in the well-known Bartlett’s test. Then it is shown that, under the transformation group given by scaling factors, a locally most powerful invariant test (LMPIT) does not exist. Two alternative approaches are explored in the low signal-to-noise ratio (SNR) regime: the first assigns a prior probability density function (pdf) to the channel (hence modeled as random), whereas the second assumes an underlying basis expansion model (BEM) for the (now deterministic) channel and obtains the maximum likelihood (ML) estimates of the parameters relevant for the detection problem. The performance of these detectors is evaluated via Monte Carlo simulation.

JF - IEEE Statistical Signal Processing Workshop (SSP 2012)
PB - IEEE
CY - Ann Arbor, MI
ER -
TY - CONF
T1 - Detection of unknown constant magnitude signals in time-varying channels
T2 - 3rd Int. Workshop on Cognitive Information Processing (CIP 2012)
Y1 - 2012
A1 - Daniel Romero
A1 - R. López-Valcarce
KW - cognitive radio
KW - dynacs
KW - spectrum sensing
AB - Spectrum sensing constitutes a key ingredient in many cognitive radio paradigms in order to detect and protect primary transmissions. Most sensing schemes in the literature assume a time-invariant channel. However, when operating in low Signal-to-Noise Ratio (SNR) conditions, observation times are necessarily long and may become larger than the coherence time of the channel. In this paper the problem of detecting an unknown constant-magnitude waveform in frequency-flat time-varying channels with noise background of unknown variance is considered. The channel is modeled using a basis expansion model (BEM) with random coefficients. Adopting a generalized likelihood ratio (GLR) approach in order to deal with nuisance parameters, a non-convex optimization problem results. We discuss different possibilities to circumvent this problem, including several low complexity approximations to the GLR test as well as an efficient fixed-point iterative method to obtain the true GLR statistic. The approximations exhibit a performance ceiling in terms of probability of detection as the SNR increases, whereas the true GLR test does not. Thus, the proposed fixed-point iteration constitutes the preferred choice in applications requiring a high probability of detection.

JF - 3rd Int. Workshop on Cognitive Information Processing (CIP 2012) CY - Baiona, Spain ER - TY - CONF T1 - Detection of video double encoding with GOP size estimation T2 - IEEE International Workshop on Information Forensics and Security (WIFS) Y1 - 2012 A1 - David Vázquez-Padín A1 - Marco Fontani A1 - Tiziano Bianchi A1 - Pedro Comesaña A1 - Alessandro Piva A1 - Mauro Barni AB -Video forensics is an emerging discipline, that aims at inferring information about the processing history undergone by a digital video in a blind fashion. In this work we introduce a new forensic footprint and, based on it, propose a method for detecting whether a video has been encoded twice; if this is the case, we also estimate the size of the Group Of Pictures (GOP) employed during the first encoding. As shown in the experiments, the footprint proves to be very robust even in realistic settings (i.e., when encoding is carried out using typical compression rates), that are rarely addressed by existing techniques.

JF - IEEE International Workshop on Information Forensics and Security (WIFS) PB - IEEE CY - Tenerife, Spain ER - TY - CONF T1 - Detection diversity of multiantenna spectrum sensors T2 - IEEE Int. Conf. on Acoustics, Speech and Signal Processing (ICASSP 2011) Y1 - 2011 A1 - Gonzalo Vázquez-Vilar A1 - R. López-Valcarce A1 - Ashish Pandharipande KW - cognitive radio KW - detection diversity KW - spectrum sensing AB -In the context of spectrum sensing, we investigate the performance of detectors equipped with M antennas (co-located or distributed) under Rayleigh fading, in terms of detection diversity. Rather than the high-SNR concept of diversity order common in the communications literature, we adopt the notion recently advocated by Daher and Adve in the radar community: the slope of the average probability of detection (\bar{P}_D) vs. SNR curve at \bar{P}_D = 0.5. This definition is well suited to spectrum sensing, which invariably deals with low SNR levels. It is shown that the diversity order grows as M for an optimal centralized detector having access to all observations, whereas for the two distributed schemes considered (the multiantenna energy detector and the OR detector) it grows no faster than √M.

JF - IEEE Int. Conf. on Acoustics, Speech and Signal Processing (ICASSP 2011)
PB - IEEE
CY - Prague, Czech Republic
ER -
TY - JOUR
T1 - Detection of Rank-P Signals in Cognitive Radio Networks With Uncalibrated Multiple Antennas
JF - IEEE Trans. on Signal Processing
Y1 - 2011
A1 - David Ramírez
A1 - Gonzalo Vázquez-Vilar
A1 - R. López-Valcarce
A1 - Javier Vía
A1 - Ignacio Santamaría
KW - cognitive radio
KW - dynacs
KW - spectrum sensing
AB - Spectrum sensing is a key component of the Cognitive Radio paradigm. Typically, primary signals have to be detected with uncalibrated receivers at signal-to-noise ratios (SNRs) well below decodability levels. Multiantenna detectors exploit spatial independence of receiver thermal noise to boost detection performance and robustness. We study the problem

of detecting a Gaussian signal with rank-P unknown spatial

covariance matrix in spatially uncorrelated Gaussian noise with

unknown covariance using multiple antennas. The generalized

likelihood ratio test (GLRT) is derived for two scenarios. In the

first one, the noises at all antennas are assumed to have the same (unknown) variance, whereas in the second, a generic diagonal noise covariance matrix is allowed in order to accommodate calibration uncertainties in the different antenna frontends. In the latter case, the GLRT statistic must be obtained numerically, for which an efficient method is presented. Furthermore, for asymptotically low SNR, it is shown that the GLRT does admit a closed form, and the resulting detector performs well in practice. Extensions are presented in order to account for unknown temporal correlation in both signal and noise, as well as frequency-selective channels.

VL - 59
IS - 8
ER -
TY - CONF
T1 - A Dirty Paper Scheme for Hierarchical OFDM
T2 - IEEE International Conference on Communications (ICC)
Y1 - 2011
A1 - Scagliola, Michele
A1 - Fernando Pérez-González
A1 - Guccione, Pietro
KW - dirty paper
KW - Hierarchical OFDM
KW - watermarking
JF - IEEE International Conference on Communications (ICC)
CY - Kioto, Japan
ER -
TY - CONF
T1 - Distributed spectrum sensing with multiantenna sensors under calibration errors
T2 - IEEE Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
Y1 - 2011
A1 - Daniel Romero
A1 - R. López-Valcarce
KW - ad hoc detectors
KW - antenna arrays
KW - calibration
KW - calibration errors
KW - cognitive radio
KW - energy detector
KW - generalized likelihood ratio
KW - log normal distribution
KW - lognormal shadowing
KW - multiantenna sensors
KW - Ricean fading
KW - spectrum sensing
KW - wireless medium
AB - Spectrum sensing design for Cognitive Radio systems is challenged by the nature of the wireless medium, which makes the detection requirements difficult to achieve by standalone sensors. To combat shadowing and fading, distributed strategies are usually proposed. However, most distributed approaches are based on the energy detector, which is not robust to noise uncertainty. This phenomenon can be overcome by multi-antenna sensors exploiting spatial independence of the noise process. We combine both ideas to develop distributed detectors for multiantenna sensors. Fusion rules are provided for sensors based on the Generalized Likelihood Ratio as well as for ad hoc detectors derived from geometric considerations. Simulation results are provided comparing the performance of the different strategies under lognormal shadowing and Ricean fading.

JF - IEEE Workshop on Signal Processing Advances in Wireless Communications (SPAWC) ER - TY - THES T1 - Design of Nonlinear Precoding and Estimation Schemes for Advanced Communication Systems Y1 - 2010 A1 - Marcos Álvarez-Díaz KW - adaptive signal processing KW - satcom VL - Ph.D. ER - TY - JOUR T1 - Dynamic spectrum leasing (DSL): A new paradigm for spectrum sharing in cognitive radio networks JF - IEEE Transactions on Vehicular Technology Y1 - 2010 A1 - Sudhaman K. Jayaweera A1 - Gonzalo Vázquez-Vilar A1 - C. Mosquera KW - cognitive radio KW - DSL KW - dynamic spectrum access KW - dynamic spectrum leasing KW - dynamic spectrum sharing KW - game theory KW - power control VL - 59 ER - TY - CONF T1 - Dynamic Spectrum Leasing (DSL) in Dynamic Channels T2 - ICC Workshop on Cognitive Radio Interfaces and Signal Processing (ICC CRISP) Y1 - 2010 A1 - Georges El-Howayek A1 - Sudhaman K. Jayaweera A1 - Kamrul Hakim A1 - Gonzalo Vázquez-Vilar A1 - C. Mosquera KW - cognitive radio KW - DSL KW - dynamic spectrum leasing KW - game theory KW - Rayleigh fading KW - time-varying channels KW - time-varying secondary system JF - ICC Workshop on Cognitive Radio Interfaces and Signal Processing (ICC CRISP) CY - Cape Town, South Africa ER - TY - CONF T1 - A Dynamic Spectrum Leasing (DSL) Framework for Spectrum Sharing in Cognitive Radio Networks T2 - Asilomar Conference on Signals, Systems and Computers Y1 - 2009 A1 - Sudhaman K. Jayaweera A1 - C. Mosquera JF - Asilomar Conference on Signals, Systems and Computers ER - TY - THES T1 - Digital Watermarking Security Y1 - 2008 A1 - Luis Pérez-Freire KW - data-hiding KW - security KW - watermarking PB - University of Vigo, Spain ER - TY - CONF T1 - Distortion Optimization of Model-Based Secure Embedding Schemes for Data-Hiding T2 - International Workshop on Information Hiding (IH) Y1 - 2008 A1 - Benjamin Mathon A1 - Patrick Bas A1 - François Cayre A1 - Fernando Pérez-González KW - data hiding KW - Distortion Optimization KW - Secure Embedding JF - International Workshop on Information Hiding (IH) CY - Santa Barbara, CA, U.S.A. ER - TY - CONF T1 - Distributed Estimation: Do Not Trust Gossips T2 - Sensor, Signal and Information Processing (SenSIP) Workshop Y1 - 2008 A1 - C. Mosquera A1 - Sudhaman K. Jayaweera KW - distributed estimation KW - sensor network JF - Sensor, Signal and Information Processing (SenSIP) Workshop CY - Sedona (Arizona) ER - TY - CONF T1 - Distributed Estimation with Noisy Exchanges T2 - IEEE International Workshop on Signal Processing Advances in Wireless Communications Y1 - 2008 A1 - C. Mosquera A1 - R. López-Valcarce A1 - Sudhaman K. Jayaweera KW - distributed estimation KW - sensor network JF - IEEE International Workshop on Signal Processing Advances in Wireless Communications CY - Recife, Brazil ER - TY - JOUR T1 - Distributed Sequential Estimation with Noisy, Correlated Observations JF - IEEE Signal Processing Letters Y1 - 2008 A1 - Sudhaman K. Jayaweera A1 - C. Mosquera VL - 15 ER - TY - CHAP T1 - Digital Satellite Communications Y1 - 2007 A1 - A. A. Rontogiannis A1 - Marcos Álvarez-Díaz A1 - M. Casadei A1 - V. Dalakas A1 - A. Duverdier A1 - F. J. González-Serrano A1 - M. Iubatti A1 - T. Javornik A1 - L. Lapierre A1 - Neri, Massimo A1 - P. Salmi PB - Springer CY - New York ER - TY - CHAP T1 - Digital Satellite Communications Y1 - 2007 A1 - C. Mosquera A1 - M. L. Boucheret A1 - M. Bousquet A1 - S. Cioni A1 - Wilfried Gappmair A1 - R. Pedone A1 - Sandro Scalise A1 - P. Skoutaridis A1 - M. Villanti PB - Springer ER - TY - CHAP T1 - Digital Satellite Communications Y1 - 2007 A1 - Sandro Scalise A1 - L. Castanet A1 - M. Luglio A1 - Neri, Massimo A1 - Marcos Álvarez-Díaz A1 - J. Bito A1 - M. Bousquet A1 - I. Frigyes A1 - P. Horvath A1 - Axel Jahn A1 - M. Krejcarek A1 - J. Lemorton A1 - S. Morosi A1 - M. A. Vázquez-Castro PB - Springer CY - New York ER - TY - CHAP T1 - Digital Satellite Communications Y1 - 2007 A1 - R. Pedone A1 - G. Albertazzi A1 - P.T. Mathiopoulos A1 - C. Mosquera A1 - N. Sagias A1 - M. Villanti PB - Springer ER - TY - CONF T1 - Disclosing secrets in watermarking and data hiding T2 - Third Wavila Challenge (WaCha) Y1 - 2007 A1 - Luis Pérez-Freire A1 - Fernando Pérez-González KW - data-hiding KW - security KW - watermarking JF - Third Wavila Challenge (WaCha) T3 - ECRYPT proceedings series from the Otto-von-Guericke University, Magdeburg, Germany CY - Saint-Malo, France ER - TY - CONF T1 - On Distortion Measures Associated to Random Desynchronization Attacks T2 - Security, Steganography, and Watermarking of Multimedia Contents Y1 - 2007 A1 - Félix Balado A1 - Fernando Pérez-González ED - Edward J. Delp ED - Ping W. Wong KW - data-hiding KW - desynchronization KW - watermarking JF - Security, Steganography, and Watermarking of Multimedia Contents T3 - Proc. of SPIE PB - SPIE CY - San Jose, California, USA ER - TY - CONF T1 - Dither modulation in the logarithmic domain T2 - International Workshop on Digital Watermarking (IWDW) Y1 - 2007 A1 - Pedro Comesaña A1 - Fernando Pérez-González KW - data-hiding KW - watermarking JF - International Workshop on Digital Watermarking (IWDW) CY - Guangzhou, China ER - TY - JOUR T1 - On distortion-compensated Dither Modulation data-hiding with repetition coding JF - IEEE Transactions on Signal Processing Y1 - 2006 A1 - Pedro Comesaña A1 - Fernando Pérez-González A1 - Félix Balado KW - data-hiding KW - watermarking VL - 54 ER - TY - CONF T1 - Detection in quantization-based watermarking: performance and security issues T2 - Security, Steganography, and Watermarking of Multimedia Contents Y1 - 2005 A1 - Luis Pérez-Freire A1 - Pedro Comesaña A1 - Fernando Pérez-González ED - Edward J. Delp ED - Ping W. Wong KW - data-hiding KW - security KW - watermarking JF - Security, Steganography, and Watermarking of Multimedia Contents T3 - Proc. of SPIE PB - SPIE CY - San Jose, California, USA VL - 5306 ER - TY - CONF T1 - Diamond contour-based phase recovery for (cross-)QAM constellations T2 - IEEE Workshop on Statistical Signal Processing (SSP) Y1 - 2005 A1 - Marcos Álvarez-Díaz A1 - R. López-Valcarce KW - adaptive signal processing KW - synchronization JF - IEEE Workshop on Statistical Signal Processing (SSP) CY - Bordeaux, France ER - TY - THES T1 - Digital image data hiding using side information Y1 - 2003 A1 - Félix Balado KW - data-hiding KW - watermarking PB - University of Vigo, Spain ER - TY - CONF T1 - Dither-Modulation Data hiding with distortion-compensation: exact performance analysis and an improved detector for JPEG attacks. T2 - IEEE International Conference on Image Processing (ICIP) Y1 - 2003 A1 - Fernando Pérez-González A1 - Pedro Comesaña A1 - Félix Balado KW - data-hiding KW - watermarking JF - IEEE International Conference on Image Processing (ICIP) PB - IEEE CY - Barcelona, Spain ER - TY - CONF T1 - DVB-S Air Interface over Railroad Satellite Channel: Performance and Extensions T2 - Baiona Workshop on Signal Processing in Communications Y1 - 2003 A1 - Marcos Álvarez-Díaz A1 - Sandro Scalise A1 - Giorgio Sciascia A1 - Rodolfo Mura A1 - Paolo Conforto A1 - Harald Ernst KW - Digital Communications KW - DVB-S KW - satellite communications JF - Baiona Workshop on Signal Processing in Communications CY - Baiona, Spain ER - TY - JOUR T1 - DCT-Domain Watermarking Techniques for Still Images: Detector Performance Analysis and a New Structure JF - IEEE Transactions on Image Processing Y1 - 2000 A1 - Juan R. Hernández A1 - Martín Amado A1 - Fernando Pérez-González KW - data-hiding KW - watermarking VL - 9 N1 - Special Issue on Image and Video Processing for Digital Libraries ER - TY - CONF T1 - Design of non-expansionist and orthogonal extension methods for tree-structured filter banks T2 - IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) Y1 - 2000 A1 - M. Elena Domínguez-Jiménez A1 - Nuria González-Prelcic JF - IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) CY - Estambul, Turkey ER - TY - CONF T1 - Data Hiding for Copyright Protection of Still Images T2 - Emerging Techniques for Communication Terminals Y1 - 1997 A1 - Juan R. Hernández A1 - Fernando Pérez-González A1 - José M. Rodríguez KW - data-hiding KW - watermarking JF - Emerging Techniques for Communication Terminals PB - ENSEEIHT CY - Tolouse, France ER -