scholarly journals Possibilities of further improvement of 1 s fluxgate variometers

2017 ◽  
Vol 6 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Andriy Marusenkov
Keyword(s):  
Signal To Noise Ratio ◽  
Current Source ◽  
Temperature Stability ◽  
Low Noise ◽  
High Temperature Stability ◽  
Geomagnetic Variations ◽  
Noise Characteristics ◽  
Short Period ◽  
Earth Magnetic Field ◽  
Digitally Controlled

Abstract. The paper discusses the possibility of improving temperature and noise characteristics of fluxgate variometers. The new fluxgate sensor with a Co-based amorphous ring core is described. This sensor is capable of improving the signal-to-noise ratio at the recording short-period geomagnetic variations. Besides the sensor performance, it is very important to create the high-stability compensation field that cancels the main Earth magnetic field inside the magnetic cores. For this purpose the new digitally controlled current source with low noise level and high temperature stability is developed.

scholarly journals Possibilities of further improvement of 1-second fluxgate variometers

2017 ◽  
Author(s):  
Andriy Marusenkov
Keyword(s):  
Current Source ◽  
Temperature Stability ◽  
Low Noise ◽  
High Temperature Stability ◽  
Geomagnetic Variations ◽  
Sensor Performance ◽  
Noise Characteristics ◽  
Short Period ◽  
Earth Magnetic Field ◽  
Digitally Controlled

Abstract. The paper discusses the possibility to improve temperature and noise characteristics of fluxgate variometers. The new fluxgate sensor with a Co-based amorphous ring core is described. This sensor is capable to improve the signal-noise ratio at the recording short-period geomagnetic variations. Besides the sensor performance, it is very important to create the high stability compensation field, which is canceling the main Earth magnetic field inside the magnetic cores. For this purpose the new digitally controlled current source with low noise level and high temperature stability is developed.

Seismic noise characteristics in Chinese mainland

2020 ◽  
Author(s):  
Fang Wang ◽  
Weitao Wang ◽  
Jianfeng Long ◽  
Leiyu Mu
Keyword(s):  
Noise Level ◽  
Seismic Noise ◽  
Vertical Component ◽  
Chinese Mainland ◽  
Low Noise ◽  
Noise Characteristics ◽  
Power Spectral ◽  
Short Period ◽  
Power Spectral Densities ◽  
Noise Models

<p>Using the three-component continuous waveform recordings of 880 broadband seismic stations in China Seismic Network from January 2014 to December 2015, we calculated power spectral densities and probability density functions over the entire period for each station，and  investigated the characteristics of seismic noise in Chinese mainland. The deep analysis on the vertical recordings  indicates that the spatial distribution of noise levels is characterized by obvious zoning for different period bands.  Densely populated areas have higher short-period noise level than sparsely populated ones, suggesting that short-period noise is related to the intensity distribution of human activities such as transportation and industry. Meanwhile，the short-period noise level near the basin is higher than the mountainous areas，which is probably caused by the amplification effect of the sedimentary layer. The microseism energy  gradually decreases from the southeastern coastal lines to the inland regions. Furthermore, horizontal-component noise level  showed a striking constrast with the vertical component at microseismic and long-period bands. In consideration of  the zoning chracteristics and the need of seismic observations, high and low noise models were  acquired for each network , which were proved to be a more effective tool to identify locally abnormal signals including earthquake, instrumental error and various distrubance compared with the global new high and low model. </p>

Research of Precision Conditioning Circuit in Laser Differential Confocal Sensor

2012 ◽  
Vol 241-244 ◽  
pp. 815-821
Author(s):  
Jun Jie Guo ◽  
Li Rong Qiu ◽  
Wei Qian Zhao
Keyword(s):  
Light Intensity ◽  
High Precision ◽  
Signal To Noise Ratio ◽  
Low Noise ◽  
Photoelectric Conversion ◽  
Measurement Systems ◽  
Noise Characteristics ◽  
Voltage Signal ◽  
Conversion Unit ◽  
Conditioning Circuit

Laser differential confocal sensor (LDCS) is a high precision and high integrated measurement system. In order to meet the demand of the LDCS, a novel implementation method of high precision conditioning circuit is studied. This circuit consists of photoelectric conversion, secondary amplification and signal operation. The photoelectric conversion is designed to detect the light intensity signal and transform it into a voltage signal. In order to adapt the test for different samples, the magnification is adjustable in secondary amplification unit. The two-way light intensity signals of the LDCS are differentially subtracted in signal operation unit. The noise characteristics of the photoelectric conversion unit were analyzed and the methods for decreasing noise were presented. The experimental results show that signal to noise ratio (SNR) of the conditioning circuit is better than 1160 and the sensitivity of LDCS reaches 2.168V/μm, which has the advantages of low noise, high stability and high integration and can widely used in many kinds of high precision photoelectric measurement systems.

Spectral and Noise Characteristics of a Xenon Microwave-Induced Plasma Lamp

1986 ◽  
Vol 40 (3) ◽  
pp. 379-385 ◽  
Author(s):  
D. Beauchemin ◽  
J. Hubert ◽  
M. Moisan
Keyword(s):  
Signal To Noise Ratio ◽  
Visible Region ◽  
Optical Emission ◽  
Low Noise ◽  
Optical Emission Spectrum ◽  
Visible Radiation ◽  
Noise Characteristics ◽  
Uv Visible ◽  
Short Arc ◽  
The Continuum

Xenon lamps, filled at various pressures from 0.9 to 5 atmospheres and activated by an electromagnetic-surface-wave-produced plasma, are evaluated for their optical spectrum characteristics in the uv-visible region. The influence of several operating parameters on their optical emission spectrum and noise characteristics is reported. These microwave-induced lamps are compared with a commercial 150 W high-pressure xenon short-arc lamp in regard to their use as continuous sources of uv-visible radiation. They are more stable but are less intense than the short arc. Furthermore, the intensity of the line spectrum that is superimposed on the continuum is comparatively larger than with the short arc. The results obtained indicate, however, that it is possible to decrease the line intensities with respect to the continuum intensity as well as to improve the signal-to-noise ratio and to increase the total emitted intensity by increasing the gas pressure and/or the microwave power. These lamps may thus be considered as potential highly stable, low-noise spectrometric continuum sources.

UNS N06455

Alloy Digest ◽  
1989 ◽  
Vol 38 (1) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Stress Corrosion Cracking ◽  
Temperature Stability ◽  
Heat Treating ◽  
High Ductility ◽  
High Temperature Stability ◽  
Nickel Chromium ◽  
Long Time ◽  
Resistance To Stress

Abstract UNS NO6455 is a nickel-chromium-molybdenum alloy with outstanding high-temperature stability as shown by high ductility and corrosion resistance even after long-time aging in the range 1200-1900 F. The alloy also has excellent resistance to stress-corrosion cracking and to oxidizing atmospheres up to 1900 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-367. Producer or source: Nickel and nickel alloy producers.

UNS R54620

Alloy Digest ◽  
1987 ◽  
Vol 36 (7) ◽  
Keyword(s):  
Titanium Alloy ◽  
High Temperature ◽  
Time Use ◽  
Temperature Stability ◽  
High Strength ◽  
Heat Treating ◽  
High Temperature Stability ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Long Time

Abstract UNS No. R54620 is an alpha-beta titanium alloy. It has an excellent combination of tensile strength, creep strength, toughness and high-temperature stability that makes it suitable for service to 1050 F. It is recommended for use where high strength is required. It has outstanding advantages for long-time use at temperatures to 800 F. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-86. Producer or source: Titanium alloy mills.

Comparative Assessment of Sporophyte and Gametophyte Thermal Resistance of Winter Rape

2019 ◽  
pp. 15-22
Keyword(s):  
Elevated Temperatures ◽  
Rapid Assessment ◽  
Temperature Stability ◽  
Temperature Factor ◽  
Plant Genome ◽  
Limiting Factors ◽  
Initial Assessment ◽  
High Temperature Stability ◽  
Winter Rape ◽  
High Yields

The temperature factor is one of the limiting factors for obtaining high yields of crops, so one of the main tasks of selection is to search for temperature-resistant genotypes and to create on their basis the banks of crops with high temperature stability. The first step to solving this problem is to conduct a rapid assessment of the temperature plasticity of large populations and to isolate breeding-valuable genotypes from them. There are numerous methods that allow, in the short term with minimal technical and material costs, to carry out an initial assessment of a large number of genotypes at sporophytic level and differentiate them by resistance to the temperature factor. These methods include the method of estimating pollen populations. These studies have repeatedly been conducted on many cultures, their correctness is due to the expression of a large part of the plant genome, both at the diploid and haploid levels of development and demonstrated by many studies in this direction. The aim of our study was to study the stability of gametophyte and sporophyte of collecting varieties and varieties of winter rape to elevated temperatures, to study the correlation between the heat resistance of sporophyte and gametophyte.

scholarly journals A High Efficiency Low Noise RF-to-DC Converter Employing Gm-Boosting Envelope Detector and Offset Canceled Latch Comparator

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1078
Author(s):  
Thi Thuy Pham ◽  
Dongmin Kim ◽  
Seo-Hyeong Jeong ◽  
Junghyup Lee ◽  
Donggu Im
Keyword(s):  
Power Consumption ◽  
High Efficiency ◽  
Supply Voltage ◽  
Current Source ◽  
Low Noise ◽  
The Body ◽  
Common Source ◽  
Conversion Gain ◽  
Input Transistor ◽  
Envelope Detector

This work presents a high efficiency RF-to-DC conversion circuit composed of an LC-CL balun-based Gm-boosting envelope detector, a low noise baseband amplifier, and an offset canceled latch comparator. It was designed to have high sensitivity with low power consumption for wake-up receiver (WuRx) applications. The proposed envelope detector is based on a fully integrated inductively degenerated common-source amplifier with a series gate inductor. The LC-CL balun circuit is merged with the core of the envelope detector by sharing the on-chip gate and source inductors. The proposed technique doubles the transconductance of the input transistor of the envelope detector without any extra power consumption because the gate and source voltage on the input transistor operates in a differential mode. This results in a higher RF-to-DC conversion gain. In order to improve the sensitivity of the wake-up radio, the DC offset of the latch comparator circuit is canceled by controlling the body bias voltage of a pair of differential input transistors through a binary-weighted current source cell. In addition, the hysteresis characteristic is implemented in order to avoid unstable operation by the large noise at the compared signal. The hysteresis window is programmable by changing the channel width of the latch transistor. The low noise baseband amplifier amplifies the output signal of the envelope detector and transfers it into the comparator circuit with low noise. For the 2.4 GHz WuRx, the proposed envelope detector with no external matching components shows the simulated conversion gain of about 16.79 V/V when the input power is around the sensitivity of −60 dBm, and this is 1.7 times higher than that of the conventional envelope detector with the same current and load. The proposed RF-to-DC conversion circuit (WuRx) achieves a sensitivity of about −65.4 dBm based on 45% to 55% duty, dissipating a power of 22 μW from a 1.2 V supply voltage.

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