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Terahertz (THz) plasmonic field effect transistor sensors have emerged as prime contenders for applications in THz and sub-THz communications, biomedical sensing, and imaging. Noise is one of the most important factors determining their performance. We show that the conventional approach of using thermal noise of the device impedance for predicting the sensor performance is inadequate because it ignores...
In this paper are presented the results obtained after of evaluating three techniques of blind detection of spectrum holes used in Cognitive Radio (CR). The techniques evaluated correspond to the general technique of detection of energy levels, the method LAD BASED and the technique based on forward methods. The operation of these techniques was tested in simulation scenarios of a telecommunications...
Fiber Optic Gyroscope is an optical sensor that can determine the position of the angle of motion of an object. FOG works based on the Sagnac effect, which states that the phase shift between two opposite waves propagates in the interferometry of the rotating ring, and proportional to the angular velocity. Goodness performance indicator of measurement system, is having a small noise. Angle Random...
The sensitivity of a recently proposed spike detector exploiting the volatile properties of memristive device is optimised. A 200 nm × 200 nm TiOx memristive device in volatile region is biased with sub-threshold, unipolar and bipolar neural events. The input neural signal is pre-processed using different amplification settings. The resistive state response of the test device in response to the input...
Energy spectra, electron mobilities, resistances and noises in the semi-metallic n-type Hg0.32Cd0.68Te/Hg1−xCdxTe quantum well at T = 77 K are numerically modeled in this work. The modeling is provided on the basis of direct iterative solution of Boltzmann transport equation and accounts bands mixing, non-parabolicity of dispersion law, proper screening in 2DEG and inelasticity of electron scattering...
This paper deals with evaluation and simulation of direct detection radiometer, which operates in the W-frequency band. Radiometers can be used in wide range applications in industry, military and security as well. One of the possible applications where the radiometers can be used is scanning of concealed dangerous objects. Main part of the article deals with the theoretical analysis of the basic...
This paper presents a comparative evaluation of classical feature point descriptors when they are used in the long-wave infrared spectral band. Robustness to changes in rotation, scaling, blur, and additive noise are evaluated using a state of the art framework. Statistical results using an outdoor image data set are presented together with a discussion about the differences with respect to the results...
In this paper, we propose a new switching median filter with signal dependent thresholds designed by a genetic algorithm (GA). The switching median filter detects noise-corrupted pixels based on a threshold. Then it restores only the detected pixels. The present switching median filter deals with the random-valued impulse noises, whose distribution is ideally assumed as a uniform distribution. In...
A problem of detecting textural areas in images corrupted by noise is considered. Detection is based on joint use of several local parameters calculated in scanning windows (blocks) of different size. Trained support vector machine (SVM) classifier is used for combining local parameters. Factors that influence detector performance are analyzed. It is shown that detector performance can be improved...
Our group has designed a family of ASICs dedicated to the readout of semiconductor detectors for space applications, named IDeF-X standing for Imaging Detector Front-end [1]-[3]. IDeF-X BD is a new member of the family. It has been optimized for the readout of low capacitor and low leakage current Silicon or Cd(Zn)Te detectors. IDeF-X BD has been designed in the standard AMS CMOS 0.35 μm process technology...
We show that the sensitivity-bandwidth product of the aLIGO gravitational wave detector can be enhanced by a factor of 18, while remaining below the standard quantum limit, by employing a white light cavity configuration.
The Ge0.9Sn0.1 photoconductor was fabricated with interdigitated structures on Si using a CMOS-compatible process. Temperature-dependent responsivity and specific detectivity were measured. The peak responsivity of 2.85A/W at 77K was achieved due to enhanced photoconductive gain.
The Teager-Kaiser energy operator (TKO) belongs to a class of autocorrelators and their linear combination that can track the instantaneous energy of a nonstationary sinusoidal signal source. TKO-based monocomponent AM-FM demodulation algorithms work under the basic assumption that the operator outputs are always positive. In the absence of noise, this is assured for pure sinusoidal inputs and the...
This paper investigates the problem of change detection in multitemporal Synthetic Aperture Radar (SAR) images. Our proposition is to perform a keypoint-based algorithm to detect land-cover changes between two SAR images employing the graph theory combined with the log-ratio operator. First, a set of feature points is extracted from one of the two images. A weighted graph is then constructed to connect...
Scale-space corner detection (SSCD) has been drawing much attention in the past. Multi-scale corner detection (MSCD), which recognizes corners only at several scales, can be treated as a fast implementation of SSCD. In this paper, a new MSCD algorithm is proposed, which is based on an arithmetic mean (AM) of the k-cosine curvature values respectively computed at three scales. Compared to the existing...
We consider the problem of distributed detection involving multiple sensor nodes to jointly detect the presence of an unknown signal. To circumvent power/bandwidth constraints, a multilevel quantizer is employed in each sensor to quantize the original observation. The quantized data are transmitted through distortion channels to a fusion center where a generalized likelihood ratio test (GLRT) detector...
In this paper we propose an efficient approach for circular shape target recovery. The method makes use of the conterminous set of edge segments, or contour segments, instead of the huge edge points as traditional detectors do. First, the proposed approach computes the contour in a given image, which is then converted into contour segments at high curvature points. Then, by calculating the reinforcement...
Median filtering forensics and its anti-forensic attack have received considerable attention since median filtering can be used for both image enhancement and anti-forensic purposes. A median filtering anti-forensic attack method by adding uniformly distributed noise was proposed in an image pixel domain. However, we observe that this attack method leaves visible traces in the histogram of its median...
This paper presents the results of the study aimed at evaluating the impact of the switching section on the design of a millimeter-wave system-on-chip Dicke radiometer for the space-based detection of solar flares. The radiometer operates at the frequency of 36.8 GHz and is expected to be implemented in a 0.25 μm SiGe BiCMOS technology by IHP, under Space evaluations. System analysis and circuit simulations...
A comparison among different architectures of front-end preamplifiers for SiPM detectors is useful when relevant performance in terms of timing accuracy is required in single photon detection applications. Many different solutions have been proposed in the past, which can be grouped into three main approaches: charge sensitive amplifiers, voltage-mode amplifiers and current-mode buffers. Here these...
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