This paper presents an acoustic local positioning system (ALPS) suitable for indoor positioning

of portable devices such as smartphones or tablets, based on the transmission of high frequency

CDMA-coded signals from a fixed network of beacons. The main novelty of the proposed ALPS is

its capability to mitigate the effects of multipath propagation by performing an accurate estimation

of the Line-of-Sight Time-of-Flights (LOS-TOF) through the Matching Pursuit algorithm. Signal

detection, multipath cancellation and positioning estimation all take place within the portable device,

which provides a graphical representation of the updated position in less than a second. The

performance of the Matching Pursuit algorithm is analyzed in a real scenario and the results show

that the proposed method is capable to retrieve the multipath-free System Availability under strong

multipath conditions with SNR levels as low as 0 dB.

%B Digital Signal Processing
%V 62
%P 38-51
%8 03/2017
%G eng
%R 10.1016/j.dsp.2016.11.001
%0 Journal Article
%J IEEE Transactions on Wireless Communications
%D 2017
%T FER Estimation in a Memoryless BSC with Variable Frame Length and Unreliable ACK/NAK Feedback
%A Alberto Rico-Alvariño
%A R. López-Valcarce
%A Carlos Mosquera
%A Robert W. Heath Jr.
%K adaptive signal processing
%K compass
%K Cramér-Rao bound (CRB)
%K frame error rate
%K myrada
%K winter
%X We consider the problem of estimating the frame error rate (FER) of a given memoryless binary symmetric channel by observing the success or failure of transmitted packets. Whereas FER estimation is relatively straightforward if all observations correspond to packets with equal length, the problem becomes considerably more complex when this is not the case. We develop FER estimators when

transmissions of different lengths are observed, together with the Cramer-Rao Lower Bound (CRLB). Although the main focus is on Maximum Likelihood (ML) estimation, we also obtain low complexity schemes performing close to optimal in some scenarios. In a second stage, we consider the case in which FER estimation is performed at a node different from the receiver, and incorporate the impairment of unreliable observations by considering noisy ACK/NAK feedback links. The impact of unreliable feedback is analyzed by means of the corresponding CRLB. In this setting, the ML estimator is obtained by applying the Expectation-Maximization algorithm to jointly estimate the error probabilities of the data and feedback links. Simulation results illustrate the benefits of the proposed estimators.

%B IEEE Transactions on Wireless Communications
%V 16
%P 3661 - 3673
%8 06/2017
%G eng
%N 6
%R 10.1109/TWC.2017.2686845
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%D 2017
%T Filter design for delay-based anonymous communications
%A Simon Oya
%A Fernando Pérez-González
%A Carmela Troncoso
%K adversarial signal processing
%K compass
%K Multimedia security
%K winter
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%G eng
%0 Journal Article
%J IEEE Transactions on Signal Processing
%D 2017
%T Learning Power Spectrum Maps from Quantized Power Measurements
%A Daniel Romero
%A Seung-Jun Kim
%A Georgios Giannakis
%A R. López-Valcarce
%K cognitive radio
%K compass
%K compressed sensing
%K spectrum sensing
%K winter
%K wsn
%X Using power measurements collected by a network of low-cost sensors, power spectral density (PSD) maps are con-

structed to capture the distribution of RF power across space and frequency. Linearly compressed and quantized power measure-

ments enable wideband sensing at affordable implementation complexity using a small number of bits. Strengths of data- and model-

driven approaches are combined to develop estimators capable of incorporating multiple forms of spectral and propagation prior

information while fitting the rapid variations of shadow fading across space. To this end, novel nonparametric and semiparametric

formulations are investigated. It is shown that the desired PSD maps can be obtained using support vector machine-type solvers.

In addition to batch approaches, an online algorithm attuned to real-time operation is developed. Numerical tests assess the performance of the novel algorithms.

%B IEEE Transactions on Signal Processing
%V 65
%P 2547-2560
%8 05/2017
%G eng
%N 10
%R 10.1109/TSP.2017.2666775
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
%D 2017
%T Secure Genomic Susceptibility Testing based on Lattice Encryption
%A Juan Ramón Troncoso-Pastoriza
%A Alberto Pedrouzo-Ulloa
%A Fernando Pérez-González
%K adversarial signal processing
%K compass
%K Genomic Privacy
%K homomorphic encryption
%K Lattice-Based Cryptography
%K Privacy Protection
%B IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
%I IEEE
%C New Orleans, USA
%G eng
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
%D 2017
%T Time-domain channel estimation for wideband millimeter wave systems with hybrid architecture
%A Kiran Venugopal
%A Ahmed Alkhateeb
%A Robert W. Heath Jr.
%A Nuria González-Prelcic
%K compass
%K mmWave
%K myrada
%X Millimeter wave (mm Wave) systems will likely employ large antennas at both the transmitter and receiver for directional beamforming. Hybrid analog/digital MIMO architectures have been proposed previously for leveraging both array gain and multiplexing gain, while reducing the power consumption in analog-to-digital converters. Channel knowledge is needed to design the hybrid precoders/combiners, which is difficult to obtain due to the large antenna arrays and the frequency selective nature of the channel. In this paper, we propose a sparse recovery based time-domain channel estimation technique for hybrid architecture based frequency selective mmWave systems. The proposed compressed sensing channel estimation algorithm is shown to provide good estimation error performance, while requiring small training overhead. The simulation results show that using multiple RF chains at the receiver and the transmitter further reduces the training overhead.

%B IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) %P 6193-6197 %8 03/2017 %G eng %0 Journal Article %J Signal Processing %D 2017 %T Wideband full-duplex MIMO relays with blind adaptive self-interference cancellation %A Emilio Antonio-Rodríguez %A Stefan Werner %A R. López-Valcarce %A Taneli Riihonen %A Risto Wichman %K adaptive signal processing %K compass %K full duplex %K winter %XWe develop adaptive self-interference cancellation algorithms for both filter-and-forward and decode-and-forward

multiple-input multiple-output relays. The algorithms are blind in the sense that they only exploit the spectral properties

of the transmitted signal to identify the self-interference channel, while dealing with frequency-selective channels and

arbitrary signal spectra. Our approach is non-intrusive in the sense that the algorithms can successfully identify, track,

and cancel the self-interference distortion while the relay is operating in its normal mode. We study the stationary

points of the algorithms and analyze under which conditions they achieve perfect cancellation of the self-interference.

Simulation results show that the algorithms provide residual self-interference levels below the noise floor by using

the time samples of only a few OFDM symbols.

%B Signal Processing
%V 130
%P 74-85
%8 01/2017
%G eng
%& 74
%R 10.1016/j.sigpro.2016.06.010
%0 Conference Paper
%B 8th Advanced Satellite Multimedia Systems Conference 14th Signal Processing for Space Communications Workshop
%D 2016
%T Advanced Signal Processing Techniques for Fixed and Mobile Satellite Communications
%A Pol Henarejos
%A Ana Pérez-Neira
%A Nicolò Mazzali
%A Carlos Mosquera
%K compass
%K full duplex
%K satcom
%B 8th Advanced Satellite Multimedia Systems Conference 14th Signal Processing for Space Communications Workshop
%8 09/2016
%G eng
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%D 2016
%T Array thinnig for antenna selection in millimeter wave MIMO systems
%A C. Rusu
%A Nuria González-Prelcic
%A R. W. Heath Jr
%K compass
%K mmWave
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%8 2016
%G eng
%0 Conference Paper
%B The 17th IEEE International workshop on Signal Processing advances in Wireless Communications (SPAWC)
%D 2016
%T Bandwidth Allocation in Partial Duplex Relaying
%A Carlos Mosquera
%A R. López-Valcarce
%K compass
%K full duplex
%K relay
%B The 17th IEEE International workshop on Signal Processing advances in Wireless Communications (SPAWC)
%C Edinburgh, UK
%8 07/2016
%G eng
%0 Journal Article
%J IEEE Signal Processing Magazine
%D 2016
%T Compressive Covariance Sensing: Structure-Based Compressive Sensing Beyond Sparsity
%A Daniel Romero
%A Dyonisius D Ariananda
%A Zhi Tian
%A Geert Leus
%K compass
%K compressed sensing
%X Compressed sensing deals with the reconstruction of signals

from sub-Nyquist samples by exploiting the sparsity of their

projections onto known subspaces. In contrast, the present

article is concerned with the reconstruction of second-order

statistics, such as covariance and power spectrum, even in

the absence of sparsity priors. The framework described here

leverages the statistical structure of random processes to

enable signal compression and offers an alternative perspective

at sparsity-agnostic inference. Capitalizing on parsimonious

representations, we illustrate how compression and reconstruction

tasks can be addressed in popular applications such

as power spectrum estimation, incoherent imaging, direction

of arrival estimation, frequency estimation, and wideband

spectrum sensing.

%B IEEE Signal Processing Magazine
%V 33
%P 78--93
%8 01/2016
%G eng
%N 1
%0 Conference Paper
%B IEEE Workshop on Statistical Signal Processing (SSP)
%D 2016
%T Design of data-injection adversarial attacks against spatial field detectors
%A R. López-Valcarce
%A Daniel Romero
%K adversarial signal processing
%K compass
%K wsn
%X 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.

%B IEEE Workshop on Statistical Signal Processing (SSP) %C Palma de Mallorca, Spain %8 06/2016 %G eng %0 Journal Article %J IEEE/ACM Transactions on Networking %D 2016 %T Design of pool mixes against profiling attacks in real conditions %A Simon Oya %A Fernando Pérez-González %A Carmela Troncoso %K adversarial signal processing %K compass %B IEEE/ACM Transactions on Networking %V 24 %P 3662-3675 %8 12/2016 %G eng %N 6 %R 10.1109/TNET.2016.2547391 %0 Journal Article %J IEEE Transactions on Signal Processing %D 2016 %T Designing incoherent frames through convex techniques for optimized compressed sensing %A Cristian Rusu %A Nuria González-Prelcic %K compass %K compressed sensing %B IEEE Transactions on Signal Processing %V 64 %P 2334-2344 %8 May/2016 %G eng %N 9 %& 2334 %0 Conference Paper %B IEEE Workshop on Statistical Signal Processing (SSP) %D 2016 %T Distributed multivariate regression with unknown noise covariance in the presence of outliers: a minimum description length approach %A R. López-Valcarce %A Daniel Romero %A Josep Sala %A Alba Pagès-Zamora %K compass %K wsn %XWe 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.

%B IEEE Workshop on Statistical Signal Processing (SSP)
%C Palma de Mallorca, Spain
%G eng
%0 Conference Paper
%B Information Theory and Applications Workshop (ITA
%D 2016
%T Estimating millimeter wave channels using out-of-band measurements
%A Anum Ali
%A Nuria González-Prelcic
%A R.W. Heath Jr.
%K compass
%K mmWave
%B Information Theory and Applications Workshop (ITA
%8 January, 2016
%G eng
%0 Journal Article
%J IEEE Transactions on Signal Processing
%D 2016
%T Fast orthonormal sparsifying transforms based on Householder reflectors
%A C. Rusu
%A Nuria González-Prelcic
%A R.W. Heath Jr.
%K compass
%K compressed sensing
%B IEEE Transactions on Signal Processing
%V 64
%P 6589-6599
%8 12/2016
%G eng
%N 24
%R 10.1109/TSP.2016.2612168
%0 Conference Paper
%B Asilomar Conf. on Signals, Systems and Computers
%D 2016
%T Frequency selective multiuser hybrid precoding for mmWave systems with imperfect channel knowledge
%A Jose P. Gonzalez-Coma
%A Nuria González-Prelcic
%A Luis Castedo
%A Robert W. Heath Jr.
%K compass
%K mmWave
%B Asilomar Conf. on Signals, Systems and Computers
%8 11/2016
%G eng
%R 10.1109/ACSSC.2016.7869044
%0 Conference Paper
%B 8th Advanced Satellite Multimedia Systems Conference and 14th Signal Processing for Space Communications Workshop
%D 2016
%T Full-duplex operation in two-way broadcast service for maritime applications
%A Tomás Ramírez
%A Carlos Mosquera
%K compass
%K full duplex
%K satcom
%B 8th Advanced Satellite Multimedia Systems Conference and 14th Signal Processing for Space Communications Workshop
%8 09/2016
%G eng
%0 Conference Paper
%B IEEE Global Telecommunications Conf. (GLOBECOM)
%D 2016
%T Hybrid precoders and combiners for mmWave MIMO systems with per-antenna power constraints
%A R. López-Valcarce
%A Nuria González-Prelcic
%A Cristian Rusu
%A R. W. Heath, Jr
%K compass
%K mmWave
%X This paper considers the design of hybrid precoders

and combiners for mmWave MIMO systems with per-antenna

power constraints and the additional limitations introduced by

the phase-shifting network in the analog processing stage. Previous

hybrid designs were obtained using a total power constraint,

but in practical implementations per-antenna constraints are

more realistic, specially at mmWave, given the large number of

power amplifiers used in the transmit array. Assuming perfect

channel knowledge, we obtain first an approximation to the alldigital

solution for the precoder and the combiner given the

per-antenna constraints. Then, we develop a new method for the

design of the hybrid precoder and combiner which attempts to

match such all-digital approximation. Simulation results show

the effectiveness of the proposed approach, which performs close

to the all-digital solution.

%B IEEE Global Telecommunications Conf. (GLOBECOM)
%G eng
%0 Conference Paper
%B IEEE International Workshop on Information Forensics and Security (WIFS)
%D 2016
%T Image denoising in the encrypted domain
%A Alberto Pedrouzo-Ulloa
%A Juan Ramón Troncoso-Pastoriza
%A Fernando Pérez-González
%K compass
%K homomorphic processing
%K Image Denoising
%K Image Encryption
%K lattice cryptography
%B IEEE International Workshop on Information Forensics and Security (WIFS)
%I IEEE
%C Abu Dhabi, UAE
%8 12/2016
%G eng
%0 Conference Paper
%B 8th Advanced Satellite Multimedia Systems Conference 14th Signal Processing for Space Communications Workshop
%D 2016
%T The impact of feeder link interference in multiple gateway multibeam satellite systems
%A Vahid Joroughi
%A Carlos Mosquera
%K compass
%K satcom
%B 8th Advanced Satellite Multimedia Systems Conference 14th Signal Processing for Space Communications Workshop
%8 09/2016
%G eng
%0 Conference Paper
%B 8th Advanced Satellite Multimedia Systems Conference and 14th Signal Processing for Space Communications Workshop
%D 2016
%T Link adaptation in mobile satellite links: field trials results
%A Anxo Tato
%A Carlos Mosquera
%A Iago Gómez
%K compass
%K satcom
%B 8th Advanced Satellite Multimedia Systems Conference and 14th Signal Processing for Space Communications Workshop
%8 09/2016
%G eng
%0 Journal Article
%J International Journal of Satellite Communications and Networking
%D 2016
%T Link adaptation in mobile satellite links: schemes for different degrees of CSI knowledge
%A Alberto Rico-Alvariño
%A Jesus Arnau
%A Carlos Mosquera
%K compass
%K satcom
%B International Journal of Satellite Communications and Networking
%V 34
%P 679-694
%8 09/2016
%G eng
%N 5
%0 Journal Article
%J IEEE Trans. Wireless Communications
%D 2016
%T Low complexity hybrid precoding strategies for millimeter wave communication systems
%A Cristian Rusu
%A Roi Méndez-Rial
%A Nuria González-Prelcic
%A Robert W. Heath Jr.
%K compass
%K mmWave
%X Millimeter communication systems use large antenna arrays to provide good average received power and to take advantage of multi-stream MIMO communication. Unfortunately, due to power consumption in the analog front-end, it is impractical to perform beamforming and fully digital precoding at baseband. Hybrid precoding/combining architectures have been proposed to overcome this limitation. The hybrid structure splits the MIMO processing between the digital and analog domains, while keeping the performance close to that of the fully digital solution. In this paper, we introduce and analyze several algorithms that efficiently design hybrid precoders and combiners starting from the known optimum digital precoder/combiner, which can be computed when perfect channel state information is available. We propose several low complexity solutions which provide different trade-offs between performance and complexity. We show that the proposed iterative solutions perform better in terms of spectral efficiency and/or are faster than previous methods in the literature. All of them provide designs which perform close to the known optimal digital solution. Finally, we study the effects of quantizing the analog component of the hybrid design and show that even with coarse quantization, the average rate performance is good.

%B IEEE Trans. Wireless Communications %V 15 %P 8380 - 8393 %8 12/2016 %G eng %N 12 %R 10.1109/TWC.2016.2614495 %0 Journal Article %J IEEE Transactions on Signal Processing %D 2016 %T Multiantenna GLR detection of rank-one signals with known power spectral shape under spatially uncorrelated noise %A Josep Sala %A Gonzalo Vázquez-Vilar %A R. López-Valcarce %A Saeid Sedighi %A Abbas Taherpour %K cognitive radio %K compass %XWe establish the generalized likelihood ratio (GLR) test for a Gaussian signal of known power spectral shape and unknown rank-one spatial signature in additive white Gaussian noise with an unknown diagonal spatial correlation matrix. This is motivated by spectrum sensing problems in dynamic spectrum access (DSA), in which the temporal correlation of the primary signal can be assumed known up to a scaling, and where the noise is due to an uncalibrated receive array. For spatially independent identically distributed (i.i.d.) noise, the corresponding GLR test reduces to a scalar optimization problem, whereas the GLR detector in the general non-i.i.d. case yields a more involved expression, which can be computed via alternating optimization methods. Low signal-to-noise ratio (SNR) approximations to the detectors are given, together with an asymptotic analysis showing the influence on detection performance of the signal power spectrum and SNR distribution across antennas. Under spatial rank-P conditions, we show that the rank-one GLR detectors are consistent with a statistical criterion that maximizes the output energy of a beamformer operating on filtered data. Simulation results support our theoretical findings in that exploiting prior knowledge on the signal power spectrum can result in significant performance improvement.

%B IEEE Transactions on Signal Processing %V 64 %P 6269-6283 %8 12/2016 %G eng %N 23 %& 6269 %R 10.1109/TSP.2016.2601290 %0 Conference Paper %B European Signal Processing Conference (EUSIPCO) %D 2016 %T Online EM-based distributed estimation in sensor networks with faulty nodes %A Pere Gimenez-Febrer %A Alba Pagès-Zamora %A R. López-Valcarce %K compass %K wsn %XThis paper focuses on the problem of the distributed estimation of a parameter vector based on noisy observations regularly acquired by the nodes of a wireless sensor network and assuming that some of the nodes have faulty sensors. We propose two online schemes, both centralized and distributed, based on the Expectation-Maximization (EM) algorithm. These algorithms are able to identify and disregard the faulty nodes, and provide a refined estimate of the parameters each time instant after a new set of observations is acquired. Simulation results demonstrate that the centralized versions of the proposed online algorithms attain the same estimation error as the centralized batch EM, whereas the distributed versions come very close to matching the batch EM.

%B European Signal Processing Conference (EUSIPCO)
%C Budapest, Hungary
%8 09/2016
%G eng
%0 Journal Article
%J IEEE J. Selected Topics in Signal Processing. Special issue on Signal Processing for Millimeter Wave Wireless Communications
%D 2016
%T An overview of signal processing techniques for millimeter wave MIMO systems
%A Robert W. Heath Jr.
%A Nuria González-Prelcic
%A Sundeep Rangan
%A Wonil Roh
%A Akbar M. Sayeed
%K compass
%K mmWave
%X Communication at millimeter wave (mmWave) frequencies is defining a new era of wireless communication. The mmWave band offers higher bandwidth communication channels versus those presently used in commercial wireless systems. The applications of mmWave are immense: wireless local and personal area networks in the unlicensed band, 5G cellular systems, not to mention vehicular area networks, ad hoc networks, and wearables. Signal processing is critical for enabling the next generation of mmWave communication. Due to the use of large antenna arrays at the transmitter and receiver, combined with radio frequency and mixed signal power constraints, new multiple-input multiple-output (MIMO) communication signal processing techniques are needed. Because of the wide bandwidths, low complexity transceiver algorithms become important. There are opportunities to exploit techniques like compressed sensing for channel estimation and beamforming. This article provides an overview of signal processing challenges in mmWave wireless systems, with an emphasis on those faced by using MIMO communication at higher carrier frequencies.

%B IEEE J. Selected Topics in Signal Processing. Special issue on Signal Processing for Millimeter Wave Wireless Communications %V 10 %P 436 - 453 %8 04/2016 %G eng %N 3 %R 10.1109/JSTSP.2016.2523924 %0 Conference Paper %B Information Theory and Applications Workshop (ITA %D 2016 %T Radar aided mmWave beam alignment in V2I communications supporting antenna diversity %A Nuria González-Prelcic %A R. Méndez-Rial %A R.W. Heath Jr. %K compass %K mmWave %B Information Theory and Applications Workshop (ITA %8 January, 2016 %G eng %0 Conference Paper %B 20th International ITG Workshop on Smart Antennas (WSA) %D 2016 %T Robust analog precoding designs for millimeter wave MIMO transceivers %A Pengfei Xia %A Robert Heath %A Nuria González-Prelcic %K compass %K mmWave %B 20th International ITG Workshop on Smart Antennas (WSA) %8 March, 2016 %G eng %0 Journal Article %J IEEE Trans. Communications %D 2016 %T Robust analog precoding designs for millimeter wave MIMO transceivers with frequency and time division duplexing %A Pengfei Xia %A Robert W. Heath Jr. %A Nuria González-Prelcic %K compass %K mmWave %XMillimeter wave (mmWave) communication provides high data rates thanks to large arrays at the transmitter and receiver, coupled with large bandwidth channels. Exploiting the arrays is challenging due to the need to configure precoding at the transmitter based on the large frequency selective channel. In this paper, we exploit the power iteration principle and propose a robust analog precoding training algorithm that can be applied in both frequency division duplex transmission systems and time division duplex transmission systems with or without RF calibration. We further analyze the convergence of the proposed algorithm and show how it converges to the singular value decomposition optimality exponentially. We propose null space projection on top of the power iteration to form multiple orthogonal beams at the transmitter and receiver. Strongest tap selection with proper energy pruning is used to collect as much precoding gain as possible from a frequency selective fading channel. The exponential effective SINR mapping performance is evaluated and demonstrates that the overall approach works smoothly. Numerical simulation results demonstrate algorithm robustness and the algorithm works not only for the simplified mmWave directional channels, but also for more general rich scattering channels.

%B IEEE Trans. Communications %V 64 %P 4622 - 4634 %8 11/2016 %G eng %N 11 %R 10.1109/TCOMM.2016.2604312 %0 Journal Article %J Microwave Journal %D 2016 %T Security in automotive radar and vehicular networks %A E. R. Yeh %A J. Choi %A Nuria González-Prelcic %A C. Bhat %A R. W. Heath Jr. %K compass %K mmWave %B Microwave Journal %G eng %0 Conference Paper %B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) %D 2016 %T The use of unit norm tight measurement matrices for one-bit compressed sensing %A C. Rusu %A Nuria González-Prelcic %A R. W. Heath Jr. %K compass %K compressed sensing %XIn this paper we analyze the mean squared error (MSE) for one-bit compressed sensing schemes based on measurement matrices that correspond to unit norm tight frames. We show that, as in the unquantized case, sensing with unit norm tight frames improves the MSE in the reconstruction of sparse vectors from one-bit measurements using l1 and thresholding algorithms. From our analytical and experimental results we conclude that when implementing one-bit compressed sensing schemes with fixed measurement matrices unit norm tight frames are the measurements of choice

%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) %8 2016 %G eng %0 Conference Paper %B IEEE WoWMoM 2016 Workshop on Fifth Generation Wireless %D 2016 %T Wideband self-interference cancellation for better spectrum use %A Carlos Mosquera %K adaptive signal processing %K compass %K full duplex %B IEEE WoWMoM 2016 Workshop on Fifth Generation Wireless %8 06/2016 %G eng %0 Conference Paper %B IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP) %D 2015 %T Adaptive hybrid precoding and combining in mmWave multiuser MIMO systems based on compressed covariance estimation %A R. Méndez-Rial %A Nuria González-Prelcic %A R. W. Heath Jr. %K compass %K mmWave %B IEEE International Workshop on Computational Advances in Multi-Sensor Adaptive Processing (CAMSAP) %8 December, 2015 %G eng %0 Conference Paper %B IEEE Global Telecommunications Conf. (GLOBECOM), %D 2015 %T Adaptive one-bit compressive sensing with application to low-precision receivers at mmWave %A C. Rusu %A R. Méndez-Rial %A Nuria González-Prelcic %A R. W. Heath, Jr %K compass %K mmWave %B IEEE Global Telecommunications Conf. (GLOBECOM), %8 December, 2015 %G eng %0 Conference Paper %B European Signal Processing Conf. (EUSIPCO) %D 2015 %T Attack detectors for data aggregation in clustered sensor networks %A R. López-Valcarce %A Daniel Romero %K adversarial signal processing %K compass %K wsn %XAmong many security threats to sensor networks, compromised sensing is particularly challenging due to the fact that it cannot be addressed by standard authentication approaches. We consider a clustered scenario for data aggregation in which an attacker injects a disturbance in sensor readings. Casting the problem in an estimation framework, we systematically apply the Generalized Likelihood Ratio approach to derive attack detectors. The analysis under different attacks reveals that detectors based on similarity of means across

clusters are suboptimal, with Bartlett’s test for homoscedasticity constituting a good candidate when lacking a priori knowledge of the variance of the underlying distribution.

%B European Signal Processing Conf. (EUSIPCO)
%I EURASIP
%C Nice, France
%P 2098-2102
%8 accepted
%G eng
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%D 2015
%T An attack on antenna subset modulation for millimeter-wave communication
%A Cristian Rusu
%A Nuria González-Prelcic
%A Robert W. Heath Jr.
%K adversarial signal processing
%K compass
%K mmWave
%X Antenna subset modulation (ASM) is a physical layer security technique that is well suited for millimeter wave communication systems. The key idea is to vary the radiation pattern at the symbol rate by selecting one from a subset of patterns with a similar main lobe and different side lobes. This paper shows that ASM is not robust to an eavesdropper that makes multiple simultaneous measurements at multiple angles. The measurements are combined and used to formulate an estimation problem to undo the effects of the side lobe randomization. Simulations show the performance of the estimation algorithms and how the eavesdropper can effectively recover the information if the signal-to-noise ratio exceeds a certain threshold. Using fewer active radio frequency chains makes it harder for the attacker to recover the transmit symbol, at the expense of more grating lobes.

%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) %I IEEE %C Brisbane, Australia %P 2914-2918 %8 04/2015 %G eng %0 Conference Paper %B IEEE International Conference on Communications (ICC) %D 2015 %T Blind Satellite Inter-Gateway Interference Mitigation %A J. Arnau %A C. Mosquera %K compass %K satcom %B IEEE International Conference on Communications (ICC) %8 2015 %G eng %0 Journal Article %J IEEE Trans. Information Theory %D 2015 %T Compression Limits for Random Vectors with Linearly Parameterized Second-Order Statistics %A Daniel Romero %A R. López-Valcarce %A Geert Leus %K compass %K compressed sensing %XThe class of complex random vectors whose covariance

matrix is linearly parameterized by a basis of Hermitian

Toeplitz (HT) matrices is considered, and the maximum

compression ratios that preserve all second-order information

are derived — the statistics of the uncompressed vector must

be recoverable from a set of linearly compressed observations.

This kind of vectors arises naturally when sampling widesense

stationary random processes and features a number of

applications in signal and array processing.

Explicit guidelines to design optimal and nearly optimal

schemes operating both in a periodic and non-periodic fashion

are provided by considering two of the most common linear

compression schemes, which we classify as dense or sparse. It

is seen that the maximum compression ratios depend on the

structure of the HT subspace containing the covariance matrix of

the uncompressed observations. Compression patterns attaining

these maximum ratios are found for the case without structure as

well as for the cases with circulant or banded structure. Universal

samplers are also proposed to compress unknown HT subspaces.

%B IEEE Trans. Information Theory
%V 61
%P 1410-1425
%8 03/2015
%G eng
%N 3
%& 1410
%R 10.1109/TIT.2015.2394784
%0 Journal Article
%J IEEE Trans. Signal Processing
%D 2015
%T Cramér-Rao Bounds for SNR Estimation of Oversampled Linearly Modulated Signals
%A R. López-Valcarce
%A J. Villares
%A J. Riba
%A W. Gappmair
%A C. Mosquera
%K adaptive signal processing
%K compass
%K Cramér-Rao bound (CRB)
%K dynacs
%K oversampling
%K Signal-to-noise ratio (SNR)
%X Most Signal-to-noise ratio (SNR) estimators use the

receiver matched filter output sampled at the symbol rate, an

approach which does not preserve all information in the analog

waveform due to aliasing. Thus, it is relevant to ask whether

avoiding aliasing could improve SNR estimation. To this end, we

compute the corresponding data-aided (DA) and non-data-aided

(NDA) Cramér-Rao bounds (CRBs). We adopt a novel dual filter

framework, which is shown to be information-preserving under

suitable conditions and considerably simplifies the analysis. It is

shown that the CRB can be substantially reduced by exploiting

any available excess bandwidth, depending on the modulation

scheme, the SNR range, and the estimator (DA or NDA) type.

%B IEEE Trans. Signal Processing
%V 63
%P 1675-1683
%8 04/2015
%G eng
%N 7
%& 1675
%R 10.1109/TSP.2015.2396013
%0 Conference Paper
%B IEEE Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
%D 2015
%T Dictionary-free Hybrid Precoders and Combiners for mmWave MIMO Systems
%A Roi Méndez-Rial
%A Cristian Rusu
%A Nuria González-Prelcic
%A Robert W. Heath Jr.
%K compass
%K mmWave
%B IEEE Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
%I IEEE
%C Stockholm, Sweden
%8 06/2015
%G eng
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%D 2015
%T Distributed AoA-based Source Positioning in NLOS with Sensor Networks
%A Pere Gimenez-Febrer
%A Alba Pagès-Zamora
%A Silvana Silva Pereira
%A R. López-Valcarce
%K compass
%K wsn
%X 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.

%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%I IEEE
%C Brisbane, Australia
%8 04/2015
%G eng
%0 Conference Paper
%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%D 2015
%T Distributed TLS Estimation under Random Data Faults
%A Silvana Silva Pereira
%A Alba Pagès-Zamora
%A R. López-Valcarce
%K compass
%K wsn
%X 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.

%B IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)
%I IEEE
%C Brisbane, Australia
%8 04/2015
%G eng
%0 Thesis
%D 2015
%T Estimation, Detection, and Learning for Dynamic Spectrum Access
%A Daniel Romero
%K cognitive radio
%K compass
%K dynacs
%K wsn
%I University of Vigo
%C Vigo, Spain
%V Ph.D.
%8 05/2015
%G eng
%9 Ph.D. Thesis
%0 Journal Article
%J IEEE Transactions on Information Forensics and Security
%D 2015
%T Forensic detection of processing operator chains: recovering the history of filtered JPEG images
%A Valentina Conotter
%A Pedro Comesaña
%A Fernando Pérez-González
%K compass
%K forensics
%B IEEE Transactions on Information Forensics and Security
%G eng
%1 Accepted for publication.

%R 10.1109/TIFS.2015.2424195 %0 Conference Paper %B IEEE International Conference on Communications (ICC) %D 2015 %T Frequency Reuse in Dual Satellite Settings: an Initial Evaluation of Full Duplex Operation %A D. Martiñán-Otero %A C. Mosquera %K compass %K full duplex %K satcom %B IEEE International Conference on Communications (ICC) %G eng %0 Journal Article %J Information Processing Letters %D 2015 %T A Greedy Topology Design to Accelerate Consensus in Broadcast Wireless Sensor Networks %A Massimo Vecchio %A R. López-Valcarce %K compass %K wsn %XWe present techniques to improve convergence speed of distributed average consensus algorithms in wireless sensor networks by means of topology design. A broadcast network is assumed, so that only the transmit power of each node can be independently controlled, rather than each individual link. Starting with a maximally connected configuration in which all nodes transmit at full power, the proposed methods successively reduce the transmit power of a chosen node in order to remove one and only one link; nodes are greedily selected either in order to yield fastest convergence at each step, or if they have the largest degree in the network. These greedy schemes provide a good complexity-performance tradeoff with respect to full-blown global search methods. As a side benefit, improving the convergence speed also results in savings in energy consumption with respect to the maximally connected setting.

%B Information Processing Letters %V 115 %P 408-413 %8 03/2015 %G eng %N 3 %& 408 %R 10.1016/j.ipl.2014.11.009 %0 Journal Article %J Journal of Network and Computer Applications %D 2015 %T Improving Area Coverage of Wireless Sensor Networks Via Controllable Mobile Nodes: a Greedy Approach %A Massimo Vecchio %A R. López-Valcarce %K compass %K wsn %XReliable wide-area monitoring with Wireless Sensor Networks (WSNs) remains a problem of

interest: simply deploying more nodes to cover wider areas is generally not a viable solution, due to

deployment and maintenance costs and the increase in radio interference. One possible solution

gaining popularity is based on the use of a reduced number of mobile nodes with controllable

trajectories in the monitored field. In this framework, we present a distributed technique for iteratively

computing the trajectories of the mobile nodes in a greedy fashion. The static sensor nodes actively

assist the mobile nodes in this task by means of a bidding protocol, thus participating towards the goal

of maximizing the area coverage of the monitored field. The performance of the proposed technique is

evaluated on various simulation scenarios with different number of mobile and static nodes in terms of

achieved coverage and mean time to achieve X% coverage. Comparison with previous state-of-the-art

techniques reveals the effectiveness and stability of the proposed method.

%B Journal of Network and Computer Applications
%V 48
%P 1-13
%8 02/2015
%G eng
%R 10.1016/j.jnca.2014.10.007
%0 Conference Paper
%B IEEE Int. Conference on Communications (ICC)
%D 2015
%T Low Complexity Hybrid Sparse Precoding and Combining in Millimeter Wave MIMO Systems
%A Cristian Rusu
%A Roi Méndez-Rial
%A Nuria González-Prelcic
%A Robert W. Heath Jr.
%K compass
%K mmWave
%B IEEE Int. Conference on Communications (ICC)
%I IEEE
%C London, UK
%8 06/2015
%G eng
%0 Conference Paper
%B Asilomar Conf. on Signals, Systems, and Computers
%D 2015
%T Low Resolution Adaptive Compressed Sensing for mmWave MIMO receivers
%A C. Rusu
%A Nuria González-Prelcic
%A R.W. Heath Jr.
%K compass
%K mmWave
%B Asilomar Conf. on Signals, Systems, and Computers
%8 November, 2015
%G eng
%0 Conference Paper
%B IEEE 9th International Symposium on Intelligent Signal Processing (WISP)
%D 2015
%T Multipath cancellation in broadband acoustic local positioning systems
%A Fernando J. Alvarez
%A R. López-Valcarce
%K compass
%K wsn
%X This work proposes a novel method to estimate the Line-of-Sight Time-of-Flights (LOS-TOFs) in a broadband acoustic local positioning system (ALPS) with strong multipath interference. The proposed method is based on the Matching Pursuit channel estimation algorithm that provides a low complexity approximation to the Maximum Likelihood solution for sparse channels. A multichannel version of this algorithm has been implemented to estimate a minimum of three coefficients in the channel responses of a particular ALPS, composed of four beacons that perform the simultaneous emission of BPSK modulated 255-bit Kasami codes. A statistical analysis of performance has been carried out by using a set of test signals synthetically generated to simulate different positions and reflection coefficients of the environment. The results of this analysis show the enhanced capability of the proposed method to estimate the LOS-TOFs under strong multipath interference, with respect to that of a classical system based on correlation + thresholding.

%B IEEE 9th International Symposium on Intelligent Signal Processing (WISP) %I IEEE %C Siena, Italy %8 05/2015 %G eng %R 10.1109/WISP.2015.7139174 %0 Conference Paper %B IEEE International Workshop on Signal Processing Advances in Wireless Communications, SPAWC %D 2015 %T Robust Adaptive Coding and Modulation Scheme for the Mobile Satellite Forward Link %A Alberto Rico-Alvariño %A Anxo Tato %A Carlos Mosquera %K compass %K satcom %B IEEE International Workshop on Signal Processing Advances in Wireless Communications, SPAWC %G eng %0 Conference Paper %B IEEE Int. Conference on Acoustics, Speech and Signal Processing (ICASSP) %D 2015 %T Spectrum Cartography using quantized observations %A Daniel Romero %A Seung-Jun Kim %A R. López-Valcarce %A Georgios Giannakis %K cognitive radio %K compass %K compressed sensing %K spectrum sensing %XThis work proposes a spectrum cartography algorithm used for learning the power spectrum distribution over a wide frequency band across a given geographic area. Motivated by low-complexity sensing hardware and stringent communication constraints, compressed and quantized measurements are considered. Setting out from a nonparametric regression framework, it is shown that a sensible approach leads to a support vector machine formulation. The simulated tests verify that accurate spectrum maps can be constructed using a simple sensing architecture with significant savings in the feedback.

%B IEEE Int. Conference on Acoustics, Speech and Signal Processing (ICASSP)
%I IEEE
%C Brisbane, Australia
%8 04/2015
%G eng
%0 Conference Paper
%B IEEE 16th Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
%D 2015
%T Subspace-constrained SINR optimization in MIMO full-duplex relays under limited dynamic range
%A Emilio Antonio-Rodríguez
%A R. López-Valcarce
%A Taneli Riihonen
%A Stefan Werner
%A Risto Wichman
%K adaptive signal processing
%K compass
%K full duplex
%X We propose a method for maximizing the signal-to-interference-plus-noise ratio (SINR) in a wideband full-duplex MIMO regenerative relay that accounts limited dynamic range of the receiver and transmitter impairments. Transmit and receive filters are designed at the relay, by means of an alternating minimization algorithm, to minimize the interference at the decoder input in the destination node. We impose channel shortening and subspace constraints to ensure that the received signal at the destination is not compromised. Simulation results show that the presented method significantly outperforms other constrained approaches.

%B IEEE 16th Int. Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
%I IEEE
%C Stockholm, Sweden
%8 06/2015
%G eng
%0 Conference Paper
%B EUSIPCO
%D 2015
%T An SVD Approach to Forensic Image Resampling Detection
%A David Vázquez-Padín
%A Pedro Comesaña
%A Fernando Pérez-González
%K compass
%K digital image forensics
%K resampling detection
%K SVD
%K tampering detection
%X This paper describes a new strategy for image resampling detection whenever the applied resampling factor is larger than one. Delving into the linear dependencies induced in an image after the application of an upsampling operation, we show that interpolated images belong to a subspace defined by the interpolation kernel. Within this framework, by computing the SVD of a given image block and a measure of its degree of saturated pixels per row/column, we derive a simple detector capable of discriminating between upsampled images and genuine images. Furthermore, the proposed detector shows remarkable results with blocks of small size and outperforms state-of-the-art methods.

%B EUSIPCO
%P 2112-2116
%8 09/2015
%G eng
%0 Journal Article
%J IEEE Communications Letters
%D 2014
%T Active Interference Cancellation for OFDM Spectrum Sculpting: Linear Processing is Optimal
%A Schmidt, J.F.
%A Daniel Romero
%A R. López-Valcarce
%K cognitive radio
%K compass
%K dynacs
%K spectrum shaping
%X Active interference cancellation (AIC) is a multicarrier spectrum sculpting technique which reduces the power of undesired out-of-band emissions by adequately modulating a subset of reserved cancellation subcarriers. In most schemes online complexity is a concern, and thus cancellation subcarriers have traditionally been constrained to linear combinations of the data subcarriers. Recent AIC designs truly minimizing out-of-band emission shift complexity to the offline design stage, motivating the consideration of more general mappings to improve performance. We show that there is no loss in optimality incurred by constraining these mappings to the set of linear functions.

%B IEEE Communications Letters %V 18 %P 1543-1546 %8 09/2014 %G eng %N 9 %& 1543 %R 10.1109/LCOMM.2014.2338316 %0 Conference Paper %B IEEE International Conference on Image Processing (ICIP) %D 2014 %T A Benford-Fourier JPEG compression detector %A Cecilia Pasquini %A Fernando Pérez-González %A Giulia Boato %K compass %K forensics %B IEEE International Conference on Image Processing (ICIP) %C Paris, France %G eng %R 10.1109/ICIP.2014.7026077 %0 Conference Paper %B Asilomar Conf. on Signals, Systems and Computers %D 2014 %T Channel estimation in millimeter wave MIMO systems with one-bit quantization %A Jianhua Mo %A Phil Schniter %A Nuria González-Prelcic %A Robert W. Heath Jr. %K adaptive signal processing %K compass %K mmWave %B Asilomar Conf. on Signals, Systems and Computers %G eng %R 10.1109/ACSSC.2014.7094595 %0 Conference Paper %B IEEE Global Communications Conference %D 2014 %T Circular Sparse Rulers Based On Co-prime Sampling For Compressive Power Spectrum Estimation %A Nuria González-Prelcic %A M. E. Domíngez-Jiménez %K cognitive radio %K compass %K compressed sensing %B IEEE Global Communications Conference %I IEEE %C Austin, TX %8 12/2014 %G eng %R 10.1109/GLOCOM.2014.7037272 %0 Conference Paper %B IEEE Workshop on Information Forensics and Security (WIFS) %D 2014 %T Detecting Misreporting Attacks to the Proportional Fair Scheduler %A Schmidt, J.F. %A R. López-Valcarce %K adversarial signal processing %K compass %X

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.

%B IEEE Workshop on Information Forensics and Security (WIFS)
%C Atlanta, USA
%8 12/2014
%G eng
%R 10.1109/WIFS.2014.7084310
%0 Conference Paper
%B Privacy Enhancing Technologies Symposium
%D 2014
%T Do dummies pay off? Limits of dummy traffic protection in anonymous communications
%A Simon Oya
%A Carmela Troncoso
%A Fernando Pérez-González
%K anonymous communications
%K compass
%K disclosure attacks
%K dummies
%B Privacy Enhancing Technologies Symposium
%G eng
%0 Conference Paper
%B ICASSP2014 - Signal Processing for Communications and Networking (ICASSP2014 - SPCOM)
%D 2014
%T FER prediction with variable codeword length
%A Alberto Rico-Alvariño
%A Robert W. Heath Jr.
%A Carlos Mosquera
%K adaptive signal processing
%K compass
%K dynacs
%K Effective SNR
%K FER prediction
%K PHY abstraction
%X Frame error rate (FER) prediction in wireless communication systems is an important tool with applications to system level simulations and link adaptation, among others. Although in realistic communication scenarios it is expected to have codewords of different lengths, previous work on FER prediction marginally treated the dependency of the FER on the codeword length. In this paper, we present a method to estimate the FER using codewords of different length. We derive a low complexity FER estimator for frames of different length transmitted over a binary symmetric channel of unknown error probability. We extend this technique to coded systems by the use of effective SNR FER predictors. The proposed estimation scheme is shown to outperform other simpler estimation methods.

%B ICASSP2014 - Signal Processing for Communications and Networking (ICASSP2014 - SPCOM) %C Florence, Italy %G eng %R 10.1109/ICASSP.2014.6853935 %0 Conference Paper %B IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM) %D 2014 %T How to Implement Doubly-Stochastic Matrices for Consensus-Based Distributed Algorithms %A S. Valcárcel-Macua %A C. Moreno-León %A J. S. Romero %A Silvana Silva Pereira %A Javier Zazo %A Alba Pagès-Zamora %A R. López-Valcarce %A S. Zazo %K compass %K dynacs %K wsn %XDoubly-stochastic matrices are usually required by

consensus-based distributed algorithms. We propose a simple

and efficient protocol and present some guidelines for implementing

doubly-stochastic combination matrices even in noisy,

asynchronous and changing topology scenarios. The proposed

ideas are validated with the deployment of a wireless sensor

network, in which nodes run a distributed algorithm for robust

estimation in the presence of nodes with faulty sensors.

%B IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM)
%C A Coruña, Spain
%G eng
%R 10.1109/SAM.2014.6882409
%0 Journal Article
%J IEEE Communications Magazine
%D 2014
%T MIMO precoding and combining solutions for millimeter wave systems
%A Ahmed Alkhateeb
%A Jianhua Mo
%A Nuria González-Prelcic
%A Robert W. Heath Jr.
%K adaptive signal processing
%K compass
%K mmWave
%X Millimeter-wave communication is one way to alleviate the spectrum gridlock at lower frequencies while simultaneously providing high-bandwidth communication channels. MmWave makes use of MIMO through large antenna arrays at both the base station and the mobile station to provide sufficient received signal power. This article explains how beamforming and precoding are different in MIMO mmWave systems than in their lower-frequency counterparts, due to different hardware constraints and channel characteristics. Two potential architectures are reviewed: hybrid analog/digital precoding/combining and combining with low-resolution analog- to-digital converters. The potential gains and design challenges for these strategies are discussed, and future research directions are highlighted.

%B IEEE Communications Magazine %V 52 %P 122-131 %8 12/2014 %G eng %N 12 %R 10.1109/MCOM.2014.6979963 %0 Conference Paper %B IEEE International Workshop on Information Forensics and Security (WIFS) %D 2014 %T The optimal attack to histogram-based forensic detectors is simple(x) %A Pedro Comesaña %A Fernando Pérez-González %K compass %K Multimedia security %B IEEE International Workshop on Information Forensics and Security (WIFS) %C Atlanta, GA %P 137-142 %8 12/2014 %G eng %1IEEE WIFS 2015 Best Paper Award

%0 Conference Paper %B IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM) %D 2014 %T SINR Optimization in Wideband Full-Duplex MIMO Relays under Limited Dynamic Range %A Emilio Antonio-Rodríguez %A R. López-Valcarce %A Taneli Riihonen %A Stefan Werner %A Risto Wichman %K adaptive signal processing %K compass %K full duplex %B IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM) %C A Coruña, Spain %G eng %R 10.1109/SAM.2014.6882369