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Gerstoft, Peter (author), Nannuru, Santosh (author), Mecklenbrauker, Christoph F. (author), Leus, G.J.T. (author)
The paper considers direction of arrival (DOA) estimation from long-term observations in a noisy environment. In such an environment the noise source might evolve, causing the stationary models to fail. Therefore a heteroscedastic Gaussian noise model is introduced where the variance can vary across observations and sensors. The source...
conference paper 2018
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Chepuri, S.P. (author), Eldar, Yonina C. (author), Leus, G.J.T. (author)
In this paper the focus is on sampling and reconstruction of signals supported on nodes of arbitrary graphs or arbitrary signals that may be represented using graphs, where we extend concepts from generalized sampling theory to the graph setting. To recover such signals from a given set of samples, we develop algorithms that incorporate prior...
conference paper 2018
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Manss, C. (author), Shutin, Dmitriy (author), Leus, G.J.T. (author)
In processing spatially distributed data, multi-agent robotic platforms equipped with sensors and computing capabilities are gaining interest for applications in inhospitable environments. In this work an algorithm for a distributed realization of sparse bayesian learning (SBL) is discussed for learning a static spatial process with the...
conference paper 2018
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Generowicz, B.S. (author), Leus, G.J.T. (author), Tbalvandanv, S. Soloukey (author), Van Hoogstraten, W. S. (author), Strvdis, C. (author), Bosch, J. G. (author), van der Steen, A.F.W. (author), De Zeeuwl, C. I. (author), Koekkoek, S. K.E. (author), Kruizinga, P. (author)
Current methods to measure blood flow using ultrafast Doppler imaging often make use of a Singular Value Decomposition (SVD). The SVD has been shown to be an effective way to remove clutter signals associated with slow moving tissue. Conventionally, the SVD is calculated from an ensemble of frames, after which the first dominant eigenvectors...
conference paper 2018
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Coutino, Mario (author), Chepuri, S.P. (author), Leus, G.J.T. (author)
In this work, we address the problem of identifying the underlying network structure of data. Different from other approaches, which are mainly based on convex relaxations of an integer problem, here we take a distinct route relying on algebraic properties of a matrix representation of the network. By describing what we call possible...
conference paper 2018
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Ariananda, D.D. (author), Romero, Daniel (author), Leus, G.J.T. (author)
This paper considers multiple wireless sensors that cooperatively estimate the power spectrum of the signals received from several sources. We extend our previous work on cooperative compressive power spectrum estimation to accommodate the scenario where the statistics of the fading channels experienced by different sensors are different. The...
conference paper 2018
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Ortiz-Jimenez, Guillermo (author), Coutino, Mario (author), Chepuri, S.P. (author), Leus, G.J.T. (author)
In this paper, we consider the problem of subsampling and reconstruction of signals that reside on the vertices of a product graph, such as sensor network time series, genomic signals, or product ratings in a social network. Specifically, we leverage the product structure of the underlying domain and sample nodes from the graph factors. The...
conference paper 2018
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Koekkoek, S. K.E. (author), Soloukeytbalvandany, S. (author), Generowicz, B.S. (author), Vanhoogstraten, W. S. (author), Deoude, N. L. (author), Boele, H. J. (author), Strydis, C. (author), Leus, G.J.T. (author), De Zeeuw, C. I. (author)
Functional ultrasound (fUS) is a relatively new imaging modality to study the brain with a high spatiotemporal resolution and a wide field-of-view. In fUS detailed images of cerebral blood flow and volume are used to derive functional information, as changes in local flow and/or volume may reflect neuronal activation through neurovascular...
conference paper 2018
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Pribic, Radmila (author), Leus, G.J.T. (author), Tzotzadinis, C. (author)
Data acquisition in compressive sensing (CS) is commonly believed to be less complicated, and even less costly, while performing agreeably. There is a major lack of measureable foundations supporting this optimism as the performance and complexity of a CS sensor have hardly been quantified. We aim to fill the gap by computing the performance...
conference paper 2018
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Isufi, E. (author), Di Lorenzo, Paolo (author), Banelli, Paolo (author), Leus, G.J.T. (author)
This paper proposes strategies for distributed Wiener-based reconstruction of graph signals from subsampled measurements. Given a stationary signal on a graph, we fit a distributed autoregressive moving average graph filter to a Wiener graph frequency response and propose two reconstruction strategies: i) reconstruction from a single temporal...
conference paper 2018
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Nambur Ramamohan, K. (author), Comesaña, Daniel Fernandez (author), Leus, G.J.T. (author)
In this paper, a specific reduced-channel Acoustic Vector Sensor (AVS) is proposed comprising one omni-directional microphone and only one particle velocity transducer, such that it can have an arbitrary orientation. Such a reduced transducer configuration is referred to as a Uniaxial AVS (U-AVS). The DOA performance of an array of U-AVSs is...
journal article 2018
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Wang, Jiachen (author), Xu, Hantao (author), Leus, G.J.T. (author), Vandenbosch, Guy A.E. (author)
The direction of arrival (DoA) estimation performance of three different coarray structures, namely, the nested array, the coprime sampling array, and the sparse ruler array are presented and compared. The coarray concept makes it possible to detect the DoAs of much more sources than the number of physical antennas. Crucial is that for the...
journal article 2018
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Han, J. (author), Zhang, Lingling (author), Zhang, Qunfei (author), Leus, G.J.T. (author)
Differential orthogonal frequency division multiplexing (OFDM) is practically attractive for underwater acoustic communications since it has the potential to obviate channel estimation. However, similar to coherent OFDM, it may suffer from severe inter-carrier interference over time-varying channels. To alleviate the induced performance...
journal article 2018
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van der Meulen, P.Q. (author), Kruizinga, P. (author), Bosch, J.G. (author), Leus, G.J.T. (author)
We study the optimal design of an aperture coding mask, and the optimal sensing positions of a single ultrasound sensor with a scanning configuration. In previous works, we have shown that 3D ultrasound imaging is possible using a randomly shaped coding mask with randomly chosen sensing positions. Here we propose an optimization algorithm for...
conference paper 2018
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Di Lorenzo, Paolo (author), Banelli, Paolo (author), Isufi, E. (author), Barbarossa, Sergio (author), Leus, G.J.T. (author)
The goal of this paper is to propose novel strategies for adaptive learning of signals defined over graphs, which are observed over a (randomly) time-varying subset of vertices. We recast two classical adaptive algorithms in the graph signal processing framework, namely, the least mean squares (LMS) and the recursive least squares (RLS)...
journal article 2018
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Liu, J. (author), Isufi, E. (author), Leus, G.J.T. (author)
In the field of signal processing on graphs, graph filters play a crucial role in processing the spectrum of graph signals. This paper proposes two different strategies for designing autoregressive moving average (ARMA) graph filters on both directed and undirected graphs. The first approach is inspired by Prony's method, which...
journal article 2018
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Morency, M.W. (author), Vorobyov, Sergiy A. (author), Leus, G.J.T. (author)
Source localization and spectral estimation are among the most fundamental problems in statistical and array signal processing. Methods that rely on the orthogonality of the signal and noise subspaces, such as Pisarenko's method, MUSIC, and root-MUSIC, are some of the most widely used algorithms to solve these problems. As a common feature,...
journal article 2018
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Segarra, Santiago (author), Chepuri, S.P. (author), Marques, Antonio G. (author), Leus, G.J.T. (author)
Stationarity is a cornerstone property that facilitates the analysis and processing of random signals in the time domain. Although time-varying signals are abundant in nature, in many contemporary applications the information of interest resides in more irregular domains that can be conveniently represented using a graph. This chapter reviews...
book chapter 2018
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Kruizinga, P. (author), van der Meulen, P.F. (author), Fedjajevs, A. (author), Mastik, F (author), Springeling, Geert (author), de Jong, N. (author), Bosch, J.G. (author), Leus, G.J.T. (author)
Three-dimensional ultrasound is a powerful imaging technique, but it requires thousands of sensors and complex hardware. Very recently, the discovery of compressive sensing has shown that the signal structure can be exploited to reduce the burden posed by traditional sensing requirements. In this spirit, we have designed a simple ultrasound...
journal article 2017
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Arroyo Valles, M.D.R. (author), Simonetto, A. (author), Leus, G.J.T. (author)
In wireless sensor networks, where energy is scarce, it is inefficient to have all nodes active because they consume a non-negligible amount of battery. In this paper we consider the problem of jointly selecting sensors, relays and links in a wireless sensor network where the active sensors need to communicate their measurements to one or...
journal article 2017
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