A self-interference cancelling front-end for in-band full-duplex wireless and its phase noise performance - Broek, Dirk-Jan van den; Klumperink, Eric A.M.; Nauta, Bram
This paper describes a frequency-agile RF front-end in 65nm CMOS targeting short-range full-duplex wireless communication. Complementing previous work on a self-interference cancelling receiver, this work describes the co-integrated transmitter and reports the phase noise advantages of using correlated clock resources to clock all up- and downconverters present in the system. The hardware is capable of frequency-agile operation from 0.15 to 3.5GHz carrier frequency. Measurements at 2.5 GHz indicate that the RX noise floor is only 1 dB degraded by phase noise when operated from a commercial PLL with ~ -38 dBc phase noise.
An in-band full-duplex radio receiver with a passive vector modulator downmixer for self-interference cancellation - Broek, Dirk-Jan van den; Klumperink, Eric A.M.; Nauta, Bram
In-band full-duplex (FD) wireless, i.e., simultaneous transmission and reception at the same frequency, introduces strong self-interference (SI) that masks the signal to be received. This paper proposes a receiver in which a copy of the transmit signal is fed through a switched-resistor vector modulator (VM)that provides simultaneous downmixing, phase shift, and amplitude scaling and subtracts it in the analog baseband for up to 27 dB SI-cancellation. Cancelling before active baseband amplification avoids self-blocking, and highly linear mixers keep SIinduced distortion low, for a receiver SI-to-noise-and-distortionratio (SINDR) of up to 71.5 dB in 16.25 MHz BW. When combined with a two-port...
Apparent wall-slip of colloidal hard-sphere suspensions in microchannel flow - Ghosh, S.; Ende, H.T.M. van den; Mugele, F.; Duits, M.H.G.
We investigated the dependence of the apparent slip length (β) on the particle concentration for suspensions of colloidal hard spheres flowing through microchannels with smooth walls. Hydrostatic pressure was used to pump monodisperse suspensions of 1 μm silica spheres in water–glycerol mixture through a poly(dimethylsiloxane) microchannel with rectangular cross section. Confocal scanning laser microscopy allowed accurate measurement of velocity profiles via particle tracking velocimetry. Apparent slip lengths were measured by extrapolating the velocity profiles to zero. Systematic variations were made of the particle volume fraction Φ (0.03–0.42) and the Peclet number (2–50). In these regimes the apparent slip length shows...
Sub-sampling PLL techniques - Gao, Xiang; Klumperink, Eric; Nauta, Bram
In a classical PLL, the phase detector (PD) and charge pump (CP) noise is multiplied by N2, when referred to the VCO output, due to the divide-by-N in the feedback path. It often dominates the in-band phase noise and limits the achievable PLL jitter power Figure-Of-Merit (FOM). A sub-sampling PLL uses a PD that sub-samples the high frequency VCO output with the reference clock. The PD and CP noise in this PLL is shown to be not multiplied by N2, and greatly attenuated by the high phase detection gain, leading to lower in-band phase noise and better PLL FOM. This...
Natura 2000 en Bouwen met de Natuur: een blik op de praktijkervaring in een zoektocht naar synergie tussen economie en ecologie - Vikolainen, Vera; Heldeweg, Michiel; Lulofs, Kris; Bressers, Hans
De toepassing van Europese natuurbeschermingsregels wordt bij veel infrastructurele projecten als juridische belemmering ervaren. In deze bijdrage geven de auteurs een positieve blik op de ervaringen in of nabij Natura 2000-gebieden in Noordwest-Europese estuaria en kustgebieden en stellen dat Natura 2000 niet per se een struikelblok hoeft te vormen, en dat het toepassen van innovatieve ontwerpmethoden als Bouwen met de Natuur het verschil kan maken voor de implementatie van Natura 2000 op projectniveau. Empirisch bewijs hiervoor is in veertien cases gezocht, waarbij drie verschillende onderzoeksontwerpen zijn gebruikt. Afgesloten wordt met een vooruitblik naar wat dit betekent voor de private partijen...
Assessing governance context to increase drought resilience: The case of the Drents-Friese Wold National Park - Lordkipanidze, Maia; Boer, Cheryl de; Bressers, Hans
The paper explores the connection between governance and the resilience of the Drents- Friese Wold National Park in the Netherlands. We assess the governance context that affects the implementation of measures to increase drought resilience in the Park. The Oude Willem area restoration project within the Park is studied more explicitly as one of the measures applied towards managing an area eroded due to long agricultural land use. The focus is on the governance context and process under which measures are taken rather than on the results of the implementation of the measures. The case shows that context is changing...
A model-derivation framework for timing analysis of Java sostware Systems - Yildiz, Bugra M.; Rensink, Arend; Bockisch, Christoph; Aksit, Mehmet
One of the main challenges in developing a software system is to assure that its properties fulfill the specifications. In the context of this paper, we are especially interested in timing properties. Model-based software verification is one of the approaches to achieve this. However, model-based verification requires expressive models of software systems and deriving such models is not a trivial task. Although there are a few model derivation tool proposals for the purpose of model-checking timing properties, these are dedicated tools supporting a selected set of verification techniques and as such they are not explicitly designed for coping with new...
Improved quantification for point-of-care capillary electrophoresis by adding an internal standard to the background electrolyte - Bidulock, A.C.E.; Berg, A. van den; Eijkel, J.C.T.
This paper investigates the viability of incorporating an internal standard in the background electrolyte (BGE), versus including it in the sample, to correct for chip-to-chip imprecision in disposable microchip capillary electrophoresis (μCE) devices. Two internal standards investigated previously as sample-added standards (CsCl and LiCl) were now added to the BGE, and their effects on the reproducibility of Na quantification were explored. The in-house fabricated microchips, electrophoretic protocols, and solution compositions were the same in both experiment sets, allowing us to reliably compare the two methods.
Ion-step method for surface potential sensing of silicon nanowires - Chen, Songyue; Berg, Albert van den; Eijkel, Jan
This paper presents a stimulus-response method for surface potential sensing of silicon nanowire field-effect transistors (Si-NW FETs). When an ‘ion-step’ from low to high ionic strength is given as stimulus to the surface, a change of current through the Si-NWs is measured. When the surface potential is changed from negative for a bare SiO2 surface to neutral/positive when there is poly-L-lysine adsorption, this change is measured by a change in current variation at the ion-step.
Viscoelastic fluid flow in circular narrow confinements driven by periodic pressure and potential gradients - Nguyen, T.; Berg, A. van den; Eijkel, J.C.T.
We present an in-depth analysis and analytical solution for AC hydrodynamic flow (driven by a timedependent pressure gradient and/or electric fields) of viscoelastic fluid through cylindrical micro-, nanochannels. Particularly, for this purpose we solve the linearized Poisson-Boltzmann equation together with the incompressible Cauchy’s momentum equation under no-slip boundary conditions. The resulting solutions allow us to predict the electrical current and solution flow rate. The results satisfy the Onsager reciprocal relation. The validity of these Onsager relations is important since it enables an analogy between fluidic networks in this flow configuration and electric circuits. They especially are of interest in micro-...
Electrochemical protein cleavage in a microfluidic cell with integrated boron doped diamond electrodes - Brink, Floris T.G. van den; Zhang, Tao; Ma, Lewei; Odijk, Mathieu; Olthuis, Wouter; Permentier, Hjalmar P.; Bischoff, Rainer P.H.; Berg, Albert van den
We present a microfluidic electrochemical cell with integrated boron doped diamond (BDD) electrodes which is designed for high electrochemical conversion efficiencies. With our newest developments, we aim to exploit the benefits of BDD as a novel electrode material to conduct tyrosine- and tryptophan- specific electrochemical protein cleavage for proteomics studies. Compared to traditional electrode materials, specific advantages of BDD include an extended potential window in aqueous solutions and a reduced susceptibility to fouling , which are properties that are particularly interesting for applications involving proteins or peptides .