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Active-Matrix IGZO Array with Printed Thermistor for Large-Area Thermal Imaging

van der Steen, J.L.P.J. (author), Peters, L.C.J.M. (author), Smits, E.C.P. (author), Zalar, P. (author), Gelinck, G.H. (author)

Thermal imagers conventionally consist of a suspended sensing element on support structure with patterned thermal detection layer to get good thermal isolation between sensor elements[1]. Large area and wearable thermal imaging applications require cost effective fabrication, robustness and a flexible form factor. We present a 16×16 active...

conference paper 2019

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Phase Controlled 2.6-3.5 GHz Fractional-N PLL IC

van Wanum, M. (author), de Boer, L. (author), van Vliet, F.E. (author)

This paper describes a fractional-N PLL IC with absolute phase control utilizing an on-chip loop-filter. The frequency range is 2.6 to 3.5 GHz, which covers one of the bands for future low-band 5G telecommunication systems. For phased-array operation a compact form-factor is needed as the space available for the complete front-end is limited by...

conference paper 2018

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Tracking and convergence of multi-channel kalman filters for active noise control

Berkhoff, A. (author), van Ophem, S. (author)

The feed-forward broadband active noise control problem can be formulated as a state estimation problem to achieve a faster rate of convergence than the filtered reference least mean squares algorithm and possibly also a better tracking performance. A multiple input/multiple output Kalman algorithm is used to perform this state estimation. To...

conference paper 2013

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Time-Evolving Acoustic Propagation Modeling in a Complex Ocean Environment

Colin, M.E.G.G. (author), Duda, T.F. (author), te Raa, L.A. (author), van Zon, T. (author), Haley Jr., P.J. (author), Lermusiaux, P.F.J. (author), Leslie, W.G. (author), Mirabito, C. (author), Lam, F.P.A. (author), Newhall, A.E. (author), Lin, Y.T. (author), Lynch, J.F. (author)

During naval operations, sonar performance estimates often need to be computed in-situ with limited environmental information. This calls for the use of fast acoustic propagation models. Many naval operations are carried out in challenging and dynamic environments. This makes acoustic propagation and sonar performance behavior particularly...

conference paper 2013

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Throughputs in processor sharing models for integrated stream and elastic traffic

Litjens, R. (author), van den Berg, J.L. (author), Boucherie, R.J. (author), TNO Informatie- en Communicatietechnologie (author)

We present an analytical study of throughput measures in processor sharing queuing systems with randomly varying service rates, modelling e.g. a communication link in an integrated services network carrying prioritised fixed rate stream traffic and rate-adaptive elastic traffic. A number of distinct throughput measures for the elastic traffic...

article 2008

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Flow level performance approximations for elastic traffic integrated with prioritized stream traffic

Malhotra, R. (author), van den Berg, J.L. (author), TNO Informatie- en Communicatietechnologie (author)

Almost all traffic in todays networks can be classified as being either stream or elastic. The support of these two traffic types is possible either with a Differentiated (DiffServ) or an Integrated Services (IntServ) architecture. However, both DiffServ and IntServ rely on efficient scheduling mechanisms and traffic control to meet the...

conference paper 2007

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Stochastic electromagnetic radiation of complex sources

Naus, H.W.L. (author), TNO Defensie en Veiligheid (author)

The emission of electromagnetic radiation by localized complex electric charge and current distributions is studied. A statistical formalism in terms of general dynamical multipole fields is developed. The appearing coefficients are treated as stochastic variables. Hereby as much as possible a priori physical knowledge is exploited. First...

article 2007

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Analysis of congestion periods of an m/m/∞-queue

Roijers, F. (author), Mandjes, M. (author), van den Berg, J.L. (author), TNO Informatie- en Communicatietechnologie (author)

A c-congestion period of an m/m/ ∞-queue is a period during which the number of customers in the system is continuously above level c. Interesting quantities related to a c-congestion period are, besides its duration Dc, the total area Ac above c, and the number of arrived customers Nc. In the literature Laplace transforms for these quantities...

article 2007

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Sojourn time approximations in queueing networks with feedback

Gijsen, B.M.M. (author), van der Mei, R.D. (author), Engelberts, P. (author), van den Berg, J.L. (author), van Wingerden, K.M.C. (author), TNO Informatie- en Communicatietechnologie (author)

This paper is motivated by the response-time analysis of distributed information systems, where transactions are handled by a sequence of front-end server and back-end server actions. We study sojourn times in an open queueing network with a single Processor Sharing (PS) node and an arbitrary number of M multi-server First-Come-First-Served ...

article 2006

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Correction of the effects induced by the continuous motion in airborne FMCW SAR

Meta, A. (author), Hoogeboom, P. (author), Ligthart, L.P. (author)

The combination of Frequency Modulated Continuous Wave (FMCW) technology and Synthetic Aperture Radar (SAR) leads to lightweight, cost-effective imaging sensors of high resolution. In FMCW SAR applications the conventional stop-and-go approximation used in pulse radar algorithms can be not valid anymore, therefore the motion within the sweep...

conference paper 2006

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Ill-posed inverse problem in diffraction optics: Tolerance analysis of diffractive lenses and gratings

Kalikmanov, V.I. (author), Sokolova, E.A. (author), TNO Industrie en Techniek TNO Defensie en Veiligheid (author)

A method is proposed for the prediction of deviations of the phase polynomial coefficients of diffractive optical elements from their nominal values due to fabrication errors. This problem represents an ill-posed inverse problem in diffraction optics. Its solution is based on the regularization technique resulting in an approximate stable ...

article 2006

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Robust Fusion of Irregularly Sampled Data Using Adaptive Normalized Convolution

Pham, T.Q. (author), van Vliet, L.J. (author), Schutte, K. (author), TNO Defensie en Veiligheid (author)

We present a novel algorithm for image fusion from irregularly sampled data. The method is based on the framework of normalized convolution (NC), in which the local signal is approximated through a projection onto a subspace. The use of polynomial basis functions in this paper makes NC equivalent to a local Taylor series expansion. Unlike the...

article 2006

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A Delay Filter for an ir-UWB Front-End

Bagga, S. (author), Haddad, S.A.P. (author), Serdijn, W.A. (author), Lang, J.R. (author), Busking, E.B. (author), TNO Defensie en Veiligheid (author)

A continuous-time analog delay is designed as a requirement for the autocorrelation function in the quadrature downconversion autocorrelation receiver (QDAR). An eight-order Fade approximation of its transfer function is selected to implement this delay. Subsequently, the orthonormal form is adopted, which is intrinsically semi-optimized for...

conference paper 2005

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Auditory distance perception in humans: A summary of past and present research

Zahorik, P. (author), Brungart, D.S. (author), Bronkhorst, A.W. (author), TNO Defensie en Veiligheid (author)

Although auditory distance perception is a critical component of spatial hearing, it has received substantially less scienti.c attention than the directional aspects of auditory localization. Here we summarize current knowledge on auditory distance perception, with special emphasis on recent research results. The summary will be structured...

article 2005

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Detection of small targets in a marine environment using laser radar

TNO Defensie en Veiigheid (author), Kunz, G.J. (author), Bekman, H.H.P.T. (author), Benoist, K.W. (author), Cohen, L.H. (author), van den Heuvel, J.C. (author), Putten, F.J.M. (author)

Small maritime targets, e.g., periscope tubes, jet skies, swimmers and small boats, are potential threats for naval ships under many conditions, but are difficult to detect with current radar systems due to their limited radar cross section and the presence of sea clutter. On the other hand, applications of lidar systems have shown that the...

conference paper 2005

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On the availability of a k-out-of-N system given limited spares and repair capacity under a condition based maintenance strategy

de Smidt-Destombes, K.S. (author), van der Heijden, M.C. (author), van Harten, A. (author), TNO Fysisch en Elektronisch Laboratorium (author)

This paper considers a k-out-of-N system with identical, repairable components. Maintenance is initiated when the number of failed components exceeds some critical level. After a possible set-up time, all failed components are replaced by spares. A multi-server repair shop repairs the failed components. The system availability depends on the...

article 2004

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Analysis of flow transfer times in IEEE 802.11 wireless LANs

Litjens, R. (author), Roijers, F. (author), van den Berg, H. (author), Boucherie, R.J. (author), Fleuren, M. (author)

In this paper we present an integrated packet/flow level modelling approach for analysing flow throughputs and transfer times in IEEE 802.11 WLANS. It captures the statistical characteristics of the transmission of individual packets at the MAC layer and takes into account the system dynamics due to the initiation and completion of data flow...

article 2004

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Low-dimensional modelling of numerical groundwater flow

Vermeulen, P.T.M. (author), Heemink, A.W. (author), te Stroet, C.B.M. (author)

Numerical models are often used for simulating groundwater flow. Written in state-space form, the dimension of these models is of the order of the number of grid cells used and can be very high (more than a million). As a result, these models are computationally very demanding, especially if many different scenarios have to be simulated. In this...

article 2004

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Soft sensing for gas-lift wells

Bloemen, H.H.J. (author), Belfroid, S.P.C. (author), Sturm, W.L. (author), Verhelst, F.J.P.C.M.G. (author), Technisch Physische Dienst TNO - TH (author)

This paper considers the use of extended Kalman Filtering as a soft-sensing technique for gas-lift wells. This technique is deployed for the estimation of dynamic variables that are not directly measured. Possible applications are the estimation of flow rates from pressure measurements or the estimation of parameters of a drift-flux model. By...

conference paper 2004

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Conspicuity and identifiability: efficient calibration tools for synthetic imagery

TNO Technische Menskunde (author), Toet, A. (author), Hogervorst, M.A. (author), Bijl, P. (author)

We argue that visual conspicuity and identifiability are two efficient task-related measures that can be deployed to calibrate synthetic imagery that is intended to be used for human visual search and detection tasks. The conspicuity of a target is operationally defined as the region around the center of the visual field where the target is...

conference paper 2004