scholarly journals First SIMO Harmonic Radar Based on the SFCW Concept and the HR Transfer Function

2021 ◽  
Vol 13 (24) ◽  
pp. 5088
Author(s):  
Holger Heuermann ◽  
Thomas Harzheim ◽  
Tobias Cronenbroeck
Keyword(s):  
Transfer Function ◽  
Continuous Wave ◽  
Mimo System ◽  
Stimulus Frequency ◽  
Propagation Path ◽  
Control Voltage ◽  
The Novel ◽  
Detailed Measurement ◽  
Harmonic Radar ◽  
Imaging Algorithms

This paper presents a new SIMO radar system based on a harmonic radar (HR) stepped frequency continuous wave (SFCW) architecture. Simple tags that can be electronically individually activated and deactivated via a DC control voltage were developed and combined to form an MO array field. This HR operates in the entire 2.45 GHz ISM band for transmitting the illumination signal and receives at twice the stimulus frequency and bandwidth centered around 4.9 GHz. This paper presents the development, the basic theory of a HR system for the characterization of objects placed into the propagation path in-between the radar and the reflectors (similar to a free-space measurement with a network analyzer) as well as first measurements performed by the system. Further detailed measurement series will be made available later on to other researchers to develop AI and machine learning based signal processing routines or synthetic aperture radar algorithms for imaging, object recognition, and feature extraction. For this purpose, the necessary information is published in this paper. It is explained in detail why this SIMO-HR can be an attractive solution augmenting or replacing existing systems for radar measurements in production technology for material under test measurements and as a simplified MIMO system. The novel HR transfer function, which is a basis for researchers and developers for material characterization or imaging algorithms, is introduced and metrologically verified in a well traceable coaxial setup.

INTERACTION OF TWO SEMI-CYLINDRICAL CANYONS EXCITED BY SH WAVES

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Abdul Hayir ◽  
Sinan Emre Cankaya
Keyword(s):  
Transfer Function ◽  
Infinite Series ◽  
Order Term ◽  
Closed Form Solution ◽  
Form Solution ◽  
Propagation Path ◽  
Earthquake Ground Motion ◽  
Dimensionless Frequency ◽  
Sh Waves ◽  
Incident Waves

The spectral analysis of strong earthquake ground motion needs detailed understanding of transfer function properties and source radiation along the wave propagation path. The main goal of this study is to evaluate the interaction of two semi-cylindrical canyons, which are subjected to the horizontally polarized shear-wave (SH-wave) and to find the transfer function properties of two canyons. In this study, the interaction of two semi-cylindrical canyons subjected to SH waves are considered and evaluated for a general angle of wave incidence. The method of Wave Function Expansion is derived, and the infinite series solution is obtained. Due to the complexity and convergence of infinite series including Bessel functions, the numerical results are limited. The convergence of the solution for the high frequencies requires the high order term. Moreover, the difficulties of this study come from convergence of the solution owing to interaction of two canyons having various dimensions and material properties. The closed-form solution of the problem shows that the surface topography can have prominent effects on incident waves when the wavelengths of incident motion are short compared to the radius of a canyon. The parameters, dimensions of the canyons, distance between two canyons, and the amplifications of the displacement amplitudes are obtained with respect to the incident angles of the waves and dimensionless frequency.

scholarly journals Multi Grid Chaotic Attractors with Discrete Jumps

2013 ◽  
Vol 64 (2) ◽  
pp. 118-122 ◽  
Author(s):  
Tomáš Gotthans ◽  
Zdeněk Hruboš
Keyword(s):  
Transfer Function ◽  
Electrical Circuit ◽  
Analog To Digital Converters ◽  
Chaotic Attractors ◽  
The Novel ◽  
Analog To Digital ◽  
Circuit Simulator ◽  
Step Functions ◽  
Discrete Step ◽  
Novel Approach

In this paper the discrete step functions are used in order to generate m×n scroll chaotic hypercube attractors. The design and realization of multi-scroll attractors depends on synthesizing the nonlinearity with an electrical circuit. The essence of the novel approach is in designing the transfer function with analog to digital converters connected directly without any microcomputer, instead of using standard comparator or hysteresis methods. Therefore there is no special need for synthesizing the nonlinearity towards m × n scroll chaotic attractors. The approach is verified with PSpice 16.0 circuit simulator and experimentally measured.

scholarly journals The size-of-source effect in thermography

2021 ◽  
Vol 10 (2) ◽  
pp. 179-184
Author(s):  
Helmut Budzier ◽  
Gerald Gerlach
Keyword(s):  
Transfer Function ◽  
Measurement Uncertainty ◽  
Modulation Transfer Function ◽  
Focal Plane ◽  
Propagation Path ◽  
Modulation Transfer ◽  
Diffraction Scattering ◽  
Complex Scene ◽  
Source Effect ◽  
Contrast Reduction

Abstract. In thermometry, the displayed temperature value of an object depends on the size of the object. This behaviour, also known as the size-of-source effect (SSE), might be a major cause of measurement uncertainty in a thermoscene. The SSE is caused by diffraction, scattering, reflection, aberration and digitization in the optoelectronic propagation path. The influence of diffraction and digitization (sampling and pixelization) can be described advantageously with the modulation transfer function MTF. The system MTF of an uncooled camera is determined by the diffraction in the lens (optical MTF) and the averaging of the radiation over the pixel area (pixel MTF). If the system MTF is known, the contrast reduction and, thus, the SSE can be calculated. Especially with very small objects, e.g. hotspots creating an image covering less than 4 pixel × 4 pixel on the focal plane, the displayed temperatures are much too low. When imaging large objects, such as area blackbodies, not only the edge areas are affected, but also the entire image. Finally, the contrast reduction by the MTF is explained by means of a complex scene (Siemens star).

A combined continuous wave electron paramagnetic resonance and DFT calculations of copper-doped 3∞[Cd0.98Cu0.02(prz-trz-ia)] metal–organic framework

2017 ◽  
Vol 19 (46) ◽  
pp. 31030-31038 ◽  
Author(s):  
Anastasia Kultaeva ◽  
Timur Biktagirov ◽  
Jens Bergmann ◽  
Linda Hensel ◽  
Harald Krautscheid ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Dft Calculations ◽  
Continuous Wave ◽  
Metal Organic Framework ◽  
The Novel ◽  
Paramagnetic Resonance ◽  
Metal Organic ◽  
Electron Paramagnetic ◽  
Organic Framework

Successful combination of EPR and DFT was applied for investigation the novel heteronuclear MOF compounds.

Dynamic Characteristics of Novel Ionic-Polymer-Metal-Composites

2006 ◽  
Vol 321-323 ◽  
pp. 208-211 ◽  
Author(s):  
Il Kwon Oh ◽  
Jin Han Jeon
Keyword(s):  
Large Deformation ◽  
Electric Fields ◽  
Platinum Electrode ◽  
Dynamic Deformation ◽  
Control Voltage ◽  
The Novel ◽  
Ionic Polymer Metal Composites ◽  
Ionic Polymer ◽  
Counter Ions ◽  
Polymer Metal

The IPMC, one of new sensing and actuating materials is known for the fast and flexible bending actuation upon electric fields. In this paper, we investigated the dynamic deformation characteristics of the novel IPMC according to several fabrication methods. First we studied the effect of the surface modification of metallic electrodes on the large deformation. Present results show that the sandblasting method can give more reliable and large deflections than the sandpapering method under the same control voltage because the platinum electrode can be infiltrated into the ionic-polymer by the sandblasting method. Second, the IPMC with Li+ counter ions shows more large deformation than that with any other counter ions. Also, present results show the dynamic hysteresis according to driving voltages.

scholarly journals Adaptive wideband equalization for frequency dispersion correction in HF band considering variations in interference characteristics and ionosphere parameters

2019 ◽  
Vol 30 ◽  
pp. 15021
Author(s):  
Dmitry Ivanov ◽  
Vladimir Ivanov ◽  
Vladimir Ovchinnikov ◽  
Aleksey Elsukov ◽  
Maria Ryabova
Keyword(s):  
Software Defined Radio ◽  
Continuous Wave ◽  
Software Radio ◽  
Frequency Dispersion ◽  
Propagation Path ◽  
Test Facility ◽  
Propagation Mode ◽  
Dispersion Correction ◽  
Radio Technology ◽  
Continuous Wave Signal

Paper presents the outcomes of the studies into the adaptive wideband equalization for frequency dispersion correction in HF band considering variations in interference characteristics and ionosphere parameters. The subject matter of the research were megahertz-bandwidth channels with single-hop F layer propagation mode. There are presented data on variations in the channel amplitude frequency response that are caused by the interference of magneto-ionic components (intramodal multipath). Test facility for carrying out full-scale experiments was developed with the use of Universal Software Radio Peripheral platform supported by the groundbreaking software-defined radio technology. Verification of the developed methods and algorithms was performed in the experiments on oblique sounding over the Cyprus-to-Yoshkar-Ola propagation path by the linearly frequency modulated continuous wave signal.

Decoupling Control and Simulation of Looper MIMO System for Hot Strip Rolling Mill

2013 ◽  
Vol 846-847 ◽  
pp. 360-364
Author(s):  
Shuang Ye
Keyword(s):  
Control System ◽  
Transfer Function ◽  
Mimo System ◽  
Character Theory ◽  
Hot Strip Rolling ◽  
Dynamic Configuration ◽  
Strip Rolling ◽  
Hot Strip ◽  
The Status ◽  
Looper System

An optimal multivatiable looper control system based on decoupling strategy has been developed for hot strip finishing mills. Based on the dynamic configuration of the coupling system, we can get the status space expression of the coupling loopers system. Through the tools of Matlab we make out of the transfer function of looper system. Based on Decouping-Inbariable character theory and the transfer function of looper system we gain the transfer function of the decoupling net. By using the Simulink toolbox of the Matlab language, the simulation results have shown that, after decoupled, the loopers control system performance gets much better.

scholarly journals Audiovisual Learning in Dyslexic and Typical Adults: Modulating Influences of Location and Context Consistency

2021 ◽  
Vol 12 ◽  
Author(s):  
Simone L. Calabrich ◽  
Gary M. Oppenheim ◽  
Manon W. Jones
Keyword(s):  
Episodic Memory ◽  
Learning Process ◽  
Contextual Information ◽  
Stimulus Frequency ◽  
Error Rates ◽  
Auditory Information ◽  
The Novel ◽  
Adult Readers ◽  
Multiple Exposures ◽  
Letter Sound

Learning to read involves efficient binding of visual to auditory information. Aberrant cross-modal binding skill has been observed in both children and adults with developmental dyslexia. Here, we examine the contribution of episodic memory to acquisition of novel cross-modal bindings in typical and dyslexic adult readers. Participants gradually learned arbitrary associations between unfamiliar Mandarin Chinese characters and English-like pseudowords over multiple exposures, simulating the early stages of letter-to-letter sound mapping. The novel cross-modal bindings were presented in consistent or varied locations (i.e., screen positions), and within consistent or varied contexts (i.e., co-occurring distractor items). Our goal was to examine the contribution, if any, of these episodic memory cues (i.e., the contextual and spatial properties of the stimuli) to binding acquisition, and investigate the extent to which readers with and without dyslexia would differ in their reliance on episodic memory during the learning process. Participants were tested on their ability to recognize and recall the bindings both during training and then in post-training tasks. We tracked participants’ eye movements remotely with their personal webcams to assess whether they would re-fixate relevant empty screen locations upon hearing an auditory cue—indicative of episodic memory retrieval—and the extent to which the so-called “looking-at-nothing behavior” would modulate recognition of the novel bindings. Readers with dyslexia both recognized and recalled significantly fewer bindings than typical readers, providing further evidence of their persistent difficulties with cross-modal binding. Looking-at-nothing behavior was generally associated with higher recognition error rates for both groups, a pattern that was particularly more evident in later blocks for bindings encoded in the inconsistent location condition. Our findings also show that whilst readers with and without dyslexia are capable of using stimulus consistencies in the input—both location and context—to assist in audiovisual learning, readers with dyslexia appear particularly reliant on consistent contextual information. Taken together, our results suggest that whilst readers with dyslexia fail to efficiently learn audiovisual binding as a function of stimulus frequency, they are able to use stimulus consistency—aided by episodic recall—to assist in the learning process.

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