scholarly journals Wideband centimetre range detector

2020 ◽  
Vol 224 ◽  
pp. 01034
Author(s):  
A Zikiy ◽  
P Zlaman ◽  
K Rumyantsev
Keyword(s):  
Experimental Study ◽  
Power Supply ◽  
Dynamic Range ◽  
Voltage Sensitivity ◽  
Frequency Range ◽  
Digital Oscilloscope ◽  
Standard Signal ◽  
Operating Frequency Range ◽  
Input Signals ◽  
Diode Detector

An experimental study of the diode detector of the centimeter wavelength range has been carried out. A brief description of the circuit and design is given. The experiment was carried out on an installation containing a standard signal generator, a digital oscilloscope, a power supply, and a offset panel. The results of the experiment are the amplitude and amplitude-frequency characteristics of the detector. The following parameters have been shown to be achieved: operating frequency range of at least 8-18 GHz, voltage sensitivity of at least 100 μV / μW, dynamic range of input signals at least 35 dB, voltage sensitivity unevenness of no more than 1.6 dB.

A 2/3 Dual-Modulus Prescaler Using Complementary Clocking NMOS-Like Blocks

2015 ◽  
Vol 24 (07) ◽  
pp. 1550109
Author(s):  
Meilin Wan ◽  
Zhenzhen Zhang ◽  
Wang Liao ◽  
Kui Dai ◽  
Xuecheng Zou
Keyword(s):  
Power Consumption ◽  
Power Supply ◽  
Single Phase ◽  
Cmos Technology ◽  
Operating Frequency ◽  
Low Power Consumption ◽  
Frequency Range ◽  
Differential Input ◽  
Operating Frequency Range ◽  
Simulation Results

A dual-modulus prescaler (divide-by-2/3) using complementary clocking NMOS-like blocks is presented in this paper. The prescaler can work properly for both differential and single phase input clocks. For differential input clocks, the prescaler achieves not only high operating frequency but also low power consumption since it consists of only five NMOS-like blocks. For single phase input clock, the operating frequency range is further expanded by utilizing a complementary clocks generator. Simulation results show that, in 180-nm standard CMOS technology, the proposed prescaler achieves operating frequency range of 1.7–9.0 GHz for differential input clocks and 0.5–10.2 GHz for single phase input clock. And the maximum power consumption from 1.8 V power supply is 0.92 mW and 1.32 mW for differential and single phase input clocks respectively.

scholarly journals A Low Power AC/DC Interface for Wind-Powered Sensor Nodes

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1823
Author(s):  
Mohammad Haidar ◽  
Hussein Chible ◽  
Corrado Boragno ◽  
Daniele D. Caviglia
Keyword(s):  
Low Power ◽  
Power Supply ◽  
Energy Harvester ◽  
Optimization Techniques ◽  
Sensor Nodes ◽  
Wireless Sensor ◽  
Constant Voltage ◽  
Interface Circuit ◽  
Switching Converter ◽  
Input Signals

Sensor nodes have been assigned a lot of tasks in a connected environment that is growing rapidly. The power supply remains a challenge that is not answered convincingly. Energy harvesting is an emerging solution that is being studied to integrate in low power applications such as internet of things (IoT) and wireless sensor networks (WSN). In this work an interface circuit for a novel fluttering wind energy harvester is presented. The system consists of a switching converter controlled by a low power microcontroller. Optimization techniques on the hardware and software level have been implemented, and a prototype is developed for testing. Experiments have been done with generated input signals resulting in up to 67% efficiency for a constant voltage input. Other experiments were conducted in a wind tunnel that showed a transient output that is compatible with the target applications.

FORMATION OF A SCANNING ANTENNA BASED ON A HALF-WAVE DIPOLE

2021 ◽  
pp. 20-24
Author(s):  
С.М. Фёдоров ◽  
Е.А. Ищенко ◽  
И.А. Баранников ◽  
К.А. Бердников ◽  
В.В. Кузнецова
Keyword(s):  
Short Distance ◽  
Electromagnetic Waves ◽  
High Stability ◽  
Frequency Range ◽  
Current Position ◽  
Form Complex ◽  
Operating Frequency Range ◽  
Half Wave ◽  
Focus Radiation ◽  
Antenna Systems

Рассматривается полуволновый диполь с установленным рефлектором, который позволяет производить сканирование пространства с использованием вращения рефлектора вокруг диполя. Для полученной конструкции производилось моделирование основных параметров, которые показали высокую стабильность при различных положениях рефлектора, постоянное значение коэффициента направленного действия, ширины главного лепестка. Изменение направления излучения совпадает с текущим положением рефлектора. По сравнению с ситуацией, когда у антенны отсутствовал рефлектор, КНД антенны увеличился, так как произошла фокусировка электромагнитных волн. Коэффициент полезного действия и передне-заднее отношение сохраняют высокие значения во всем диапазоне рабочих частот. Применение предложенной конструкции позволяет упростить конструкцию сканирующих антенн, так как для ее реализации требуются лишь полуволновой диполь и плоский рефлектор, установленный на малом расстоянии от источника излучения. В процессе управления характеристиками требуется вращать рефлектор вокруг диполя, при этом диполь остается неподвижным, что позволяет повысить эффективность предложенной конструкции, так как не требуется формировать сложных антенных систем или устанавливать комбинацию из нескольких антенн для фокусировки излучения в одном направлении от источника The article discusses a half-wave dipole with an installed reflector, which allows scanning space using the rotation of the reflector around the dipole. For the resulting structure, we simulated the main parameters, which showed high stability at various positions of the reflector, a constant value of the directivity factor, and the width of the main lobe. The change in the direction of radiation coincides with the current position of the reflector. Compared to the situation when the antenna did not have a reflector, the directivity of the antenna increased since the focusing of electromagnetic waves took place. The efficiency and the front-to-back ratio remain high throughout the entire operating frequency range. The use of the proposed design makes it possible to simplify the design of scanning antennas since the implementation of the proposed design requires only a half-wave dipole and a flat reflector installed at a short distance from the radiation source. In the process of controlling the characteristics, it is required to rotate the reflector around the dipole, while the dipole remains stationary, which makes it possible to increase the efficiency of the proposed design, since it is not required to form complex antenna systems or install a combination of several antennas to focus radiation in one direction from the source

scholarly journals Design of Broadband Compact Canonical Triple-Sleeve Antenna Operating in UHF Band

2021 ◽  
Vol 21 (4) ◽  
pp. 291-298
Author(s):  
Chandana SaiRam ◽  
Damera Vakula ◽  
Mada Chakravarthy
Keyword(s):  
Wireless Communication ◽  
Instantaneous Frequency ◽  
Dipole Antenna ◽  
Frequency Range ◽  
Broadband Antenna ◽  
Operating Frequency Range ◽  
Half Wave ◽  
Measurement Results ◽  
Antenna Configuration ◽  
Good Agreement

In this paper, a novel compact broadband antenna at UHF frequencies is presented with canonical shapes. Hemispherical, conical and cylindrical shapes have all been considered for antenna configuration. The designed antenna provides an instantaneous frequency range from 370 to 5,000 MHz with omnidirectional characteristics. The antenna was simulated in CST Microwave Studio, fabricated and evaluated; the results are presented. The simulated and measurement results are in good agreement. The antenna has voltage standing wave ratio (VSWR) ≤ 1.9:1 in 400–570 MHz, 2,530–3,740 MHz and 4,180–4,620 MHz; it has VSWR ≤ 3:1 over the operating frequency range 370–5,000 MHz and the measured gain varies from -0.6 to 4.5 dBi over the frequency band. The concept of canonical-shaped antenna elements and the incorporation of triple sleeves resulted in a reduction of the length of the antenna by 62% compared to the length of a half-wave dipole antenna designed at the lowest frequency. The antenna can be used for trans-receiving applications in wireless communication.

scholarly journals EXPERIMENTAL STUDY OF PERMANENT MAGNET WITH VARIABLE POWER SUPPLY

2020 ◽  
Vol 4 (10) ◽  
pp. 137-140
Author(s):  
G.R. Kumrey ◽  
S.K. Mahobia
Keyword(s):  
Experimental Study ◽  
Permanent Magnet ◽  
Power Supply ◽  
Dc Motor ◽  
Power Supplies ◽  
Rectifier Circuit ◽  
Variable Power ◽  
Step Down ◽  
Permanent Magnet Dc Motor

In this paper we are studying about maximum R.P.M. of Permanent Magnet DC Motor. In this way we are using the regulator circuit and 1Amp. 2 Amp. 3Amp. With different voltages. R.P.M. of D.C. motor is measured by the digital type tachometer. The D.C. power supplies are obtaining by the rectifier circuit and also used the step down transformer.

scholarly journals Photodetector resistant to background light noise with extended dynamic range of input signals

2021 ◽  
pp. 3-8
Author(s):  
V. M. Lipka ◽  
V. V. Ryukhtin ◽  
Yu. G. Dobrovolsky
Keyword(s):  
Dynamic Range ◽  
Automatic Gain Control ◽  
Modulation Frequency ◽  
Low Frequency ◽  
Gain Control ◽  
Ambient Air ◽  
Frequency Range ◽  
Background Light ◽  
Useful Signal ◽  
Extended Dynamic

Measurement of periodic optical information signals in the background light noise with a photodetector with extended dynamic range is an urgent task of modern electronics and thus has become the aim of this study. To increase the dynamic range of the photodetector, a new version of the automatic gain control (AGC) circuit has been developed, which consists of an AGC controller, an output photodetector amplifier and an AGC detector. The authors measured the dynamic range of the photodetector when receiving optical radiation with a wavelength of 1064 nm in the power range from 2.10–8 to 2.10–5 W at a modulation frequency of 20 kHz with the AGC on. Under these conditions, the dynamic range of the photodetector was found to be up to 67 dB. If the AGC was off, the dynamic range did not exceed 30 dB. Thus, the study made it possible to create a photodetector with an extended dynamic range up to 67 dB based on a new version of the AGC circuit. The design of the photodetector allowed choosing a useful signal of a particular modulation frequency in the frequency range from 3 to 45 kHz and effectively suppresses the frequencies caused by optical interference in the low frequency range from the frequency of the input signal of constant amplitude up to 3 kHz inclusive. This compensates the current up to 15 mA, which is equivalent to the power of light interference of about 15 mW. Further research should address the issues of reliability of the proposed photodetector design and optimization of its optical system. The photodetector can be used in geodesy and ambient air quality monitoring.

scholarly journals Detection and estimating the blood accumulation volume of brain hemorrhage in a human anatomical skull using a RF single coil

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10416
Author(s):  
Moshe Oziel ◽  
Boris Rubinsky ◽  
Rafi Korenstein
Keyword(s):  
Experimental Study ◽  
Electromagnetic Radiation ◽  
Hemorrhagic Stroke ◽  
Average Error ◽  
Tissue Fluid ◽  
Brain Hemorrhage ◽  
Scattering Parameters ◽  
Frequency Range ◽  
Single Coil ◽  
Chicken Blood

Objective An experimental study for testing a simple robust algorithm on data derived from an electromagnetic radiation device that can detect small changes in the tissue/fluid ratio in a realistic head configuration. Methods Changes in the scattering parameters (S21) of an inductive coil resulting from injections of chicken blood in the 0–18 ml range into calf brain tissue in a human anatomical skull were measured over a 100–1,000 MHz frequency range. Results An algorithm that combines amplitude and phase results was found to detect changes in the tissue/fluid ratio with 90% accuracy. An algorithm that estimated the injected blood volume was found to have a 1–4 ml average error. This demonstrates the possibility of the inductive coil-based device to possess a practical ability to detect a change in the tissue/fluid ratio in the head. Significance This study is an important step towards the goal of building an inexpensive and safe device that can detect an early brain hemorrhagic stroke.

scholarly journals A Cylindrical Wideband Conformal Fractal Antenna for GPS Application

2017 ◽  
Vol 6 (3) ◽  
pp. 64
Author(s):  
R. Sahoo ◽  
D. Vakula
Keyword(s):  
Conformal Geometry ◽  
Ground Plane ◽  
Antenna Design ◽  
Fractal Antenna ◽  
Frequency Range ◽  
Bandwidth Enhancement ◽  
Conformal Antenna ◽  
Operating Frequency Range ◽  
Definition Of ◽  
Good Agreement

In this paper, a novel wideband conformal fractal antenna is proposed for GPS application. The concepts of fractal and partial ground are used in conformal antenna design for miniaturization and bandwidth enhancement. It comprises of Minkowski fractal patch on a substrate of Rogers RT/duroid 5880 with permittivity 2.2 and thickness of 0.787mm with microstrip inset feed. The proposed conformal antenna has a patch dimension about 0.39λmm×0.39λmm, and partial ground plane size is 29mm×90mm.The proposed antenna is simulated, fabricated and measured for both planar and conformal geometry, with good agreement between measurements and simulations. The size of the fractal patch is reduced approximately by 32% as compared with conventional patch. It is observed that the conformal antenna exhibits a fractional bandwidth(for the definition of -10dB) of 43.72% operating from 1.09 to 1.7GHz, which is useful for L1(1.56-1.58GHz), L2(1.21-1.23GHz), L3(1.37-1.39GHz), L4(1.36-1.38GHz), and L5(1.16-1.18 GHz) in GPS and Galileo frequencies: E=1589.742MHz(4MHzbandwidth), E2=1561. 098MHz(4MHzbandwidth), E5a=1176.45MHz(=L5),E5b= 1207.14MHz, and E6=1278.75MHz(40MHz bandwidth). The radiation pattern exhibits an omnidirectional pattern, and gain of proposed antenna is 2.3dBi to 3.5dBi within operating frequency range.

The Application of Grey Prediction on the Fast Control Power Supply in EAST

2013 ◽  
Vol 427-429 ◽  
pp. 1739-1742
Author(s):  
Hai Hong Huang ◽  
Jia Miao ◽  
Hai Xin Wang ◽  
Feng Feng Wang
Keyword(s):  
Input Signal ◽  
Power Supply ◽  
Grey Theory ◽  
Grey Prediction ◽  
Grey System ◽  
Control Power ◽  
Input Signals ◽  
Simulation And Experiment ◽  
One Step ◽  
Fast Control

Based on the grey theory, a novel model is built to predict the input signal of fast control power supply used in Experimental Advanced Superconducting Tokamak (EAST). The model can be used as online metabolic grey filtering and one-step prediction of different input signals. Results of simulation and experiment show that the predicting algorithm based on the grey system model can predict the input signal primarily.

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