Dynamic Behavior of T-beam Resonator With Repulsive Actuation

Abstract We introduce a MEMS resonator that uses a "T"-shape beam driven by repulsive force, of which the first advantage is to avoid pull-in instability; thus, high enough voltages can be applied to the MEMS system to tune the center frequency. A T-beam model is derived from the beam-paddle hypothesis, and theoretical analysis regarding both static and dynamic behaviors, including primary resonance and secondary resonance, is conducted. This study shows an electrostatic T-beam resonator's feasibility based on repulsive force and outlines its advantages over a traditional cantilever beam resonator. Additional micro-paddle to the micro-beam means larger surface for absorption of targeted analytes and lower natural frequency, but higher resonant responses. We present a thorough analysis of primary and parametric resonances, which can enhance the system signal-to noise ratio and response time. This design enables potential applications in MEMS mass-sensors, where a large area for attachment and a high resolution are often vital.

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Multiple Narrowband Interferences Characterization, Detection and Mitigation Using Simplified Welch Algorithm and Notch Filtering

Applied Sciences ◽

10.3390/app11031331 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1331

Author(s):

Mohammad Hossein Same ◽

Gabriel Gleeton ◽

Gabriel Gandubert ◽

Preslav Ivanov ◽

Rene Jr Landry

Keyword(s):

Power Spectrum ◽

Embedded System ◽

Radio Frequency ◽

Satellite Communication ◽

Signal To Noise Ratio ◽

Center Frequency ◽

Infinite Impulse Response ◽

Frequency Variation ◽

Welch Method ◽

The Embedded System

By increasing the demand for radio frequency (RF) and access of hackers and spoofers to low price hardware and software defined radios (SDR), radio frequency interference (RFI) became a more frequent and serious problem. In order to increase the security of satellite communication (Satcom) and guarantee the quality of service (QoS) of end users, it is crucial to detect the RFI in the desired bandwidth and protect the receiver with a proper mitigation mechanism. Digital narrowband signals are so sensitive into the interference and because of their special power spectrum shape, it is hard to detect and eliminate the RFI from their bandwidth. Thus, a proper detector requires a high precision and smooth estimation of input signal power spectral density (PSD). By utilizing the presented power spectrum by the simplified Welch method, this article proposes a solid and effective algorithm that can find all necessary interference parameters in the frequency domain while targeting practical implantation for the embedded system with minimum complexity. The proposed detector can detect several multi narrowband interferences and estimate their center frequency, bandwidth, power, start, and end of each interference individually. To remove multiple interferences, a chain of several infinite impulse response (IIR) notch filters with multiplexers is proposed. To minimize damage to the original signal, the bandwidth of each notch is adjusted in a way that maximizes the received signal to noise ratio (SNR) by the receiver. Multiple carrier wave interferences (MCWI) is utilized as a jamming attack to the Digital Video Broadcasting-Satellite-Second Generation (DVB-S2) receiver and performance of a new detector and mitigation system is investigated and validated in both simulation and practical tests. Based on the obtained results, the proposed detector can detect a weak power interference down to −25 dB and track a hopping frequency interference with center frequency variation speed up to 3 kHz. Bit error ratio (BER) performance shows 3 dB improvement by utilizing new adaptive mitigation scenario compared to non-adaptive one. Finally, the protected DVB-S2 can receive the data with SNR close to the normal situation while it is under the attack of the MCWI jammer.

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Parametrically Excited Electrostatic MEMS Cantilever Beam With Flexible Support

Journal of Vibration and Acoustics ◽

10.1115/1.4034954 ◽

2016 ◽

Vol 139 (2) ◽

Cited By ~ 9

Author(s):

Mark Pallay ◽

Shahrzad Towfighian

Keyword(s):

Cantilever Beam ◽

Large Amplitude ◽

Chaotic Behavior ◽

Signal To Noise Ratio ◽

Mass Sensors ◽

Flexible Support ◽

Sensing Applications ◽

Electrostatic Mems ◽

Fringe Fields ◽

Steady State Amplitude

Parametric resonators that show large amplitude of vibration are highly desired for sensing applications. In this paper, a microelectromechanical system (MEMS) parametric resonator with a flexible support that uses electrostatic fringe fields to achieve resonance is introduced. The resonator shows a 50% increase in amplitude and a 50% decrease in threshold voltage compared with a fixed support cantilever model. The use of electrostatic fringe fields eliminates the risk of pull-in and allows for high amplitudes of vibration. We studied the effect of decreasing boundary stiffness on steady-state amplitude and found that below a threshold chaotic behavior can occur, which was verified by the information dimension of 0.59 and Poincaré maps. Hence, to achieve a large amplitude parametric resonator, the boundary stiffness should be decreased but should not go below a threshold when the chaotic response will appear. The resonator described in this paper uses a crab-leg spring attached to a cantilever beam to allow for both translation and rotation at the support. The presented study is useful in the design of mass sensors using parametric resonance (PR) to achieve large amplitude and signal-to-noise ratio.

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A large area diamond-based beam tagging hodoscope for ion therapy monitoring

EPJ Web of Conferences ◽

10.1051/epjconf/201817009005 ◽

2018 ◽

Vol 170 ◽

pp. 09005 ◽

Cited By ~ 4

Author(s):

M.-L. Gallin-Martel ◽

L. Abbassi ◽

A. Bes ◽

G. Bosson ◽

J. Collot ◽

...

Keyword(s):

Detection Efficiency ◽

Signal To Noise Ratio ◽

Therapy Monitoring ◽

Chemical Vapor ◽

X Rays ◽

Reaction Products ◽

Large Area ◽

Position Measurement ◽

Set Up ◽

Good Signal

The MoniDiam project is part of the French national collaboration CLaRyS (Contrôle en Ligne de l’hAdronthérapie par RaYonnements Secondaires) for on-line monitoring of hadron therapy. It relies on the imaging of nuclear reaction products that is related to the ion range. The goal here is to provide large area beam detectors with a high detection efficiency for carbon or proton beams giving time and position measurement at 100 MHz count rates (beam tagging hodoscope). High radiation hardness and intrinsic electronic properties make diamonds reliable and very fast detectors with a good signal to noise ratio. Commercial Chemical Vapor Deposited (CVD) poly-crystalline, heteroepitaxial and monocrystalline diamonds were studied. Their applicability as a particle detector was investigated using α and β radioactive sources, 95 MeV/u carbon ion beams at GANIL and 8.5 keV X-ray photon bunches from ESRF. This facility offers the unique capability of providing a focused (~1 μm) beam in bunches of 100 ps duration, with an almost uniform energy deposition in the irradiated detector volume, therefore mimicking the interaction of single ions. A signal rise time resolution ranging from 20 to 90 ps rms and an energy resolution of 7 to 9% were measured using diamonds with aluminum disk shaped surface metallization. This enabled us to conclude that polycrystalline CVD diamond detectors are good candidates for our beam tagging hodoscope development. Recently, double-side stripped metallized diamonds were tested using the XBIC (X Rays Beam Induced Current) set-up of the ID21 beamline at ESRF which permits us to evaluate the capability of diamond to be used as position sensitive detector. The final detector will consist in a mosaic arrangement of double-side stripped diamond sensors read out by a dedicated fast-integrated electronics of several hundreds of channels.

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Image Acquisition Using Non-Pixeled Amorphous Silicon Based Sensors

MRS Proceedings ◽

10.1557/proc-685-d5.17.1 ◽

2001 ◽

Vol 685 ◽

Author(s):

M. Fernandes ◽

Yu. Vygranenko ◽

J. Martins ◽

M. Vieira

Keyword(s):

Amorphous Silicon ◽

Signal To Noise Ratio ◽

Image Acquisition ◽

Short Circuit ◽

Acquisition Time ◽

Large Area ◽

Signal To Noise ◽

Scanning Beam ◽

Noise Ratio ◽

Silicon Based

AbstractWe suggest to enhance the performance of image acquisition systems based on large area amorphous silicon based sensors by optimizing the readout parameters such as the intensity and cross-section of scanner beam, acquisition time and bias conditions. The main output device characteristics as image responsivity, signal to noise ratio and spatial resolution were analyzed in open circuit, short circuit and photodiode modes. The result show that the highest signal to noise ratio and best dark to bright ratio can be achieved in short circuit mode.It was shown that the sensor resolution is related to the basic device parameters and, in practice, limited by the acquisition time and scanning beam properties. The scanning beam spot size limits the resolution due to the overlapping of dark and illuminated zones leading to a blurring effect on the final image and a consequent degradation in the resolution.

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Differential Recordings of Local Field Potential:A Genuine Tool to Quantify Functional Connectivity

10.1101/270439 ◽

2018 ◽

Author(s):

Meyer Gabriel ◽

Caponcy Julien ◽

Paul A. Salin ◽

Comte Jean-Christophe

Keyword(s):

Functional Connectivity ◽

Local Field ◽

Signal To Noise Ratio ◽

Field Potential ◽

Low Frequency ◽

Large Area ◽

Signal To Noise ◽

Cortical Areas ◽

Electrophysiological Method ◽

Local Field Potential Lfp

AbstractLocal field potential (LFP) recording is a very useful electrophysiological method to study brain processes. However, this method is criticized for recording low frequency activity in a large area of extracellular space potentially contaminated by distal activity. Here, we theoretically and experimentally compare ground-referenced (RR) with differential recordings (DR). We analyze electrical activity in the rat cortex with these two methods. Compared with RR, DR reveals the importance of local phasic oscillatory activities and their coherence between cortical areas. Finally, we show that DR provides a more faithful assessment of functional connectivity caused by an increase in the signal to noise ratio, and of the delay in the propagation of information between two cortical structures.

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High-Sensitivity Large-Area Photodiode Read-Out Using a Divide-and-Conquer Technique

Sensors ◽

10.3390/s20216316 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6316

Author(s):

Guillermo Royo ◽

Carlos Sánchez-Azqueta ◽

Concepción Aldea ◽

Santiago Celma

Keyword(s):

Traditional Approach ◽

Signal To Noise Ratio ◽

High Sensitivity ◽

Divide And Conquer ◽

Transimpedance Amplifier ◽

Large Area ◽

Signal To Noise ◽

Remarkable Improvement ◽

The Core ◽

Novel Technique

In this letter, we present a novel technique to increase the sensitivity of optical read-out with large integrated photodiodes (PD). It consists of manufacturing the PD in several pieces, instead of a single device, and connecting a dedicated transimpedance amplifier (TIA) to each of these pieces. The output signals of the TIAs are combined, achieving a higher signal-to-noise ratio than with the traditional approach. This work shows a remarkable improvement in the sensitivity and transimpedance without the need for additional modifications or compensation techniques. As a result, an increase in sensitivity of 7.9 dBm and transimpedance of 8.7 dBΩ for the same bandwidth is achieved when dividing the photodiode read-out into 16 parallel paths. The proposed divide-and-conquer technique can be applied to any TIA design, and it is also independent of the core amplifier structure and fabrication process, which means it is compatible with every technology allowing the integration of PDs.

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Large-Area Thermal Distribution Sensor Based on Multilayer Graphene Ink

Sensors ◽

10.3390/s20185188 ◽

2020 ◽

Vol 20 (18) ◽

pp. 5188

Author(s):

Tomi Koskinen ◽

Taneli Juntunen ◽

Ilkka Tittonen

Keyword(s):

Signal To Noise Ratio ◽

Graphene Film ◽

Multilayer Graphene ◽

Wearable Electronics ◽

Large Area ◽

Sensor Applications ◽

Thermal Distribution ◽

Sensing Applications ◽

Detection Of Objects ◽

Distribution Mapping

Emergent applications in wearable electronics require inexpensive sensors suited to scalable manufacturing. This work demonstrates a large-area thermal sensor based on distributed thermocouple architecture and ink-based multilayer graphene film. The proposed device combines the exceptional mechanical properties of multilayer graphene nanocomposite with the reliability and passive sensing performance enabled by thermoelectrics. The Seebeck coefficient of the spray-deposited films revealed an inverse thickness dependence with the largest value of 44.7 μV K−1 at 78 nm, which makes thinner films preferable for sensor applications. Device performance was demonstrated by touch sensing and thermal distribution mapping-based shape detection. Sensor output voltage in the latter application was on the order of 300 μV with a signal-to-noise ratio (SNR) of 35, thus enabling accurate detection of objects of different shapes and sizes. The results imply that films based on multilayer graphene ink are highly suitable to thermoelectric sensing applications, while the ink phase enables facile integration into existing fabrication processes.

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RapidNano: Towards 20nm Particle Detection on EUV Mask Blanks

MRS Advances ◽

10.1557/adv.2016.299 ◽

2016 ◽

Vol 1 (31) ◽

pp. 2225-2236 ◽

Cited By ~ 2

Author(s):

Jacques van der Donck ◽

Peter Bussink ◽

Erik Fritz ◽

Peter van der Walle

Keyword(s):

Particle Size ◽

Signal To Noise Ratio ◽

Semiconductor Industry ◽

Optical Design ◽

Dark Field ◽

Detection Methods ◽

Next Generation ◽

Large Area ◽

Dark Field Imaging ◽

20 Nm

ABSTRACTCleanliness is a prerequisite for obtaining economically feasible yield levels in the semiconductor industry. For the next generation of lithographic equipment, EUV lithography, the size of yield-loss inducing particles for the masks will be smaller than 20 nm. Consequently, equipment for handling EUV masks should not add particles larger than 20 nm. Detection methods for 20 nm particles on large area surfaces are needed to qualify the equipment for cleanliness. Detection of 20 nm particles is extremely challenging, not only because of the particle size, but also because of the large surface area and limited available time.In 2002 TNO developed the RapidNano, a platform that is capable of detecting nanoparticles on flat substrates. Over the last decade, the smallest detectable particle size was decreased while the inspection rate was increased. This effort has led to a stable and affordable detection platform that is capable of inspecting the full surface of a mask blank.The core of RapidNano is a dark-field imaging technique. Every substrate type has a typical background characteristic, which strongly affects the size of the smallest detectable particle. The noise level is induced by the speckle generated by the surface roughness of the mask. The signal-to-noise ratio can be improved by illuminating the inspection area from nine different angles. This improvement was first shown on test bench level and then applied in the RapidNano3. The RapidNano3 is capable of detecting 42nm latex sphere equivalents (and larger) on silicon surfaces. RapidNano4, the next generation, will use 193 nm light and the same nine angle illumination mode. Camera sensitivity and available laser power determine the achievable throughput. Therefore, special care was given to the optical design, particularly the optical path. With RapidNano4, TNO will push the detection limit of defects on EUV blanks to below 20nm.

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Improvements in Thallium Bromoiodide Photodetectors for Scintillation Spectrometers

MRS Proceedings ◽

10.1557/proc-302-329 ◽

1993 ◽

Vol 302 ◽

Author(s):

J.G. Zhang ◽

L. Cirignano ◽

K. Daley ◽

M.R. Squillante

Keyword(s):

High Performance ◽

Carrier Mobility ◽

High Dielectric Constant ◽

Signal To Noise Ratio ◽

Charge Carrier Mobility ◽

Large Area ◽

Semiconductor System ◽

Rotation Technique ◽

High Dielectric ◽

Crucible Rotation

ABSTRACTThallium bromoiodide, a tuneable band gap semiconductor system, was investigated as a photodetector for scintillation spectrometers. Extensive zone refining of starting materials, based on numerical simulations, considerably enhanced the electrical resistivity to 1011 Ωcm. In addition, accelerated crucible rotation technique (ACRT) crystal growth and after-growth annealing have improved the charge carrier mobility-lifetime product. However, a relatively low signal-to-noise ratio due to a high dielectric constant and relatively low quantum efficiency continues to be an obstacle to achieving high performance, large area T1BrxI1−xphotodetectors.

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Three-Component Microseismic Data Denoising Based on Re-Constrain Variational Mode Decomposition

Applied Sciences ◽

10.3390/app112210943 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10943

Author(s):

Zhili Chen ◽

Peng Wang ◽

Zhixian Gui ◽

Qinghui Mao

Keyword(s):

Signal To Noise Ratio ◽

Solution Process ◽

Vertical Component ◽

Microseismic Monitoring ◽

Center Frequency ◽

Variational Mode Decomposition ◽

Denoising Method ◽

Microseismic Data ◽

Mode Decomposition ◽

Processing Step

Microseismic monitoring is an important technology used to evaluate hydraulic fracturing, and denoising is a crucial processing step. Analyses of the characteristics of acquired three-component microseismic data have indicated that the vertical component has a higher signal-to-noise ratio (SNR) than the two horizontal components. Therefore, we propose a new denoising method for three-component microseismic data using re-constrain variational mode decomposition (VMD). In this method, it is assumed that there is a linear relationship between the modes with the same center frequency among the VMD results of the three-component data. Then, the decomposition result of the vertical component is used as a constraint to the whole denoising effect of the three-component data. On the basis of VMD, we add a constraint condition to form the re-constrain VMD, and deduce the corresponding solution process. According to the synthesis data analysis, the proposed method can not only improve the SNR level of three-component records, it also improves the accuracy of polarization analysis. The proposed method also achieved a satisfactory effect for field data.

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