High frequency noise power spectrum, impedance and transmission loss of power line in Japan on intrabuilding power line communications

1988 ◽  
Vol 34 (2) ◽  
pp. 321-326 ◽  
Author(s):  
M. Tanaka
Keyword(s):  
Power Spectrum ◽  
High Frequency ◽  
Transmission Loss ◽  
Power Line ◽  
Frequency Noise ◽  
Noise Power ◽  
Noise Power Spectrum ◽  
High Frequency Noise ◽  
Power Line Communications

Reducing the High-Frequency Noise Power in the Automatic Control System Signal by Using Comb Filters

Vestnik MEI ◽  
2020 ◽  
Vol 6 (6) ◽  
pp. 91-100
Author(s):  
Mikhail A. Babochkin ◽  
◽  
Oleg S. Kolosov ◽  
Anna A. Kuznetsova ◽  
◽  
...  
Keyword(s):  
Automatic Control ◽  
Control Systems ◽  
High Frequency ◽  
Frequency Noise ◽  
Noise Power ◽  
High Frequency Noise ◽  
Automatic Control Systems ◽  
Frequency Responses ◽  
Comb Filters ◽  
Frequency Properties

The article addresses the matter of reducing the power of high-frequency noise in the control signal produced by industrial automatic systems through the use of algorithms implementing the properties of comb filters in microprocessor controllers. The specific features relating to the frequency responses of open- and closed-loop automatic control systems of industrial facilities are analyzed - both taken alone and in combination with the characteristics of comb filters. The frequency properties of three filter groups that are conventionally used in continuous automatic control systems are compared with three groups of comb filters that implement similar functions. As applied to control tasks, such filters include real differentiating sections or first-order high-pass filters, first-order lag sections or low-pass filters, and proportional sections. The ratios between the parameters of continuous filters and comb filters at which their frequency properties coincide in the operating frequency band are determined. These ratios known, it becomes possible to synthesize the controllers of systems using the existing techniques. It is shown that the amplitude-frequency responses of comb filters have dips in the high-frequency band, due to which the high frequency noise power is finally decreased by up to 30%. The advantage of comb filters in control systems lies in simplicity of implementing them in digital form in a microprocessor controller. The application of comb filters in automatic control systems makes it possible to cut undesirable harmonic noise of large amplitude in the control signal.

Noise properties of a single ZnO nanowire device

2008 ◽  
Vol 1080 ◽  
Author(s):  
Choi Soo Han ◽  
Dong Wook Kim ◽  
Do Young Jang ◽  
Hyun Jin Ji ◽  
Sang Woo Kim ◽  
...  
Keyword(s):  
Power Spectrum ◽  
Field Effect Transistors ◽  
Electrical Contact ◽  
Low Frequency ◽  
Frequency Noise ◽  
Noise Power ◽  
Noise Amplitude ◽  
Noise Power Spectrum ◽  
Low Frequency Noise ◽  
Zno Nanowire

ABSTRACTThe low frequency noise of individual ZnO nanowire (NW) field effect transistors (FETs) exposed to air is systematically characterized. The measured noise power spectrum shows a classical 1/f type. The noise amplitude is independent of source-drain current and inversely proportional to gate voltage. The extracted Hooge's constant of ZnO NW is found to be 6.52×10−3. In addition, the low frequency noise of ZnO NW according to NW resistance and contact property are investigated. The noise amplitude is proportional to the square of ZnO NW resistance. If a sample shows a nonlinear current-voltage (I-V) characteristic due to a poor electrical contact, the noise power spectrum is proportional to the third power of current instead of the square of current.

DIFFUSION AND HIGH-FREQUENCY NOISE OF ELECTRONS IN AMORPHOUS SEMICONDUCTORS AT LOW ELECTRIC FIELDS

2012 ◽  
Vol 11 (03) ◽  
pp. 1242004 ◽  
Author(s):  
FABRIZIO BUSCEMI ◽  
ENRICO PICCININI ◽  
MASSIMO RUDAN ◽  
ROSSELLA BRUNETTI ◽  
CARLO JACOBONI
Keyword(s):  
Electric Fields ◽  
High Frequency ◽  
Transport Model ◽  
Amorphous Semiconductors ◽  
Localized States ◽  
Velocity Autocorrelation Function ◽  
Frequency Noise ◽  
Noise Power ◽  
Hopping Transport ◽  
High Frequency Noise

The Ohmic conduction, diffusion, and high-frequency noise in amorphous semiconductors are here investigated by means of a Monte Carlo implementation of a full three-dimensional variable-range hopping transport model between localized states. Quantities like the carrier-velocity autocorrelation function, the noise power spectrum, the diffusion coefficient and the ohmic conductivity are obtained from numerical simulations at room and lower temperatures. Some interesting features of the linear-response regime typical of hopping transport are observed and discussed.

scholarly journals Reconfigurable Architectures with High-Frequency Noise Suppression for Wearable ECG Devices

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
V. Joseph Michael Jerard ◽  
M. Thilagaraj ◽  
K. Pandiaraj ◽  
M. Easwaran ◽  
Petchinathan Govindan ◽  
...  
Keyword(s):  
High Frequency ◽  
Critical Path ◽  
Moving Average ◽  
Well Being ◽  
Frequency Noise ◽  
Ecg Signal ◽  
Noise Power ◽  
High Frequency Noise ◽  
Clock Speed ◽  
Look Ahead

Recent advances in electronics and microelectronics have aided the development of low-cost devices that are widely used as well-being or preventive monitoring devices by many people. Remote health monitoring, which includes wearable sensors, actuators, and modern communication and information systems, offers effective programs that allow people to live peacefully in their own homes while also being protected in some way. High-frequency noise, power-line interface, and baseline drift are prevalent during the data-acquisition system of an ECG signal, and they can limit signal understanding. They (noises) must be isolated in order to provide an appropriate diagnostic of the patient. When removing high-frequency components (noise) from an ECG signal with an FIR filter, the critical path delay increases considerably as the filter's duration increases. To reduce high-frequency noise, simple moving average filters with pipelining and look-ahead transformation techniques are extensively used in this study. With the use of pipelining and look-ahead techniques, the only objective is to increase the clock speed of the designs. The moving average filters (conventional and proposed) were created on an Altera Cyclone IV FPGA EP4CE115F29C7 chip using the Quartus II software v13.1 tool. Finally, performance metrics such logic elements, clock speed, and power consumption were compared and studied thoroughly. The recursive pipelined 8-tap MA filter with look-ahead approach outperforms the other designs (685.48 MHz) in this investigation.

Case study: Simulation and control of high frequency noise for commercial vehicle cab considering leak

2019 ◽  
Vol 67 (4) ◽  
pp. 315-329
Author(s):  
Rongjiang Tang ◽  
Zhe Tong ◽  
Weiguang Zheng ◽  
Shenfang Li ◽  
Li Huang
Keyword(s):  
High Frequency ◽  
Commercial Vehicle ◽  
Frequency Noise ◽  
High Frequency Noise ◽  
Simulation And Control ◽  
And Control

Aerodynamic noise from an asymmetric airfoil with perforated extension plates at the trailing edge

2020 ◽  
pp. 1475472X2097838
Author(s):  
CK Sumesh ◽  
TJS Jothi
Keyword(s):  
High Frequency ◽  
Sound Pressure ◽  
Pore Diameter ◽  
Low Frequency ◽  
Aerodynamic Noise ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Trailing Edge ◽  
High Frequency Noise ◽  
Displacement Thickness

This paper investigates the noise emissions from NACA 6412 asymmetric airfoil with different perforated extension plates at the trailing edge. The length of the extension plate is 10 mm, and the pore diameters ( D) considered for the study are in the range of 0.689 to 1.665 mm. The experiments are carried out in the flow velocity ( U∞) range of 20 to 45 m/s, and geometric angles of attack ( αg) values of −10° to +10°. Perforated extensions have an overwhelming response in reducing the low frequency noise (<1.5 kHz), and a reduction of up to 6 dB is observed with an increase in the pore diameter. Contrastingly, the higher frequency noise (>4 kHz) is observed to increase with an increase in the pore diameter. The dominant reduction in the low frequency noise for perforated model airfoils is within the Strouhal number (based on the displacement thickness) of 0.11. The overall sound pressure levels of perforated model airfoils are observed to reduce by a maximum of 2 dB compared to the base airfoil. Finally, by varying the geometric angle of attack from −10° to +10°, the lower frequency noise is seen to increase, while the high frequency noise is observed to decrease.

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