Absorbing Elements Based on a Uniform Resistive Film for the Implementation of a Wide Range of Radio Signal Power Attenuations

2019 ◽  
Vol 48 (7) ◽  
pp. 516-521
Author(s):  
V. D. Sadkov ◽  
K. S. Fomina ◽  
A. V. Pil’kevich
Keyword(s):  
Radio Signal ◽  
Signal Power ◽  
Resistive Film ◽  
Wide Range ◽  
Absorbing Elements

Thin-Film Absorbing Elements of Adapter-Attenuators for HIC

2021 ◽  
Vol 26 (6) ◽  
pp. 521-532
Author(s):  
A.V. Pilkevich ◽  
◽  
V.D. Sadkov ◽  
Keyword(s):  
Integrated Circuits ◽  
Power Density ◽  
Potential Gradient ◽  
Pulse Mode ◽  
Transformation Coefficient ◽  
Resistive Film ◽  
Input And Output ◽  
Wide Range ◽  
Film Element ◽  
Absorbing Elements

One of the urgent tasks in the design of hybrid integrated circuits (HIC) is the construction of adapter-attenuators – film absorbing elements providing a wide range of attenuations with specified values of input and output resistances. Known variants of adapter-attenuators based on a homogeneous and piecewise homogeneous resistive film provide (by introducing asymmetry in the dimensions of the input and output contacts, changing the location of a piecewise homogeneous resistive film, introducing dielectric or conductive regions) a resistance transformation coefficient of no more than 3 and 10–12, respectively. In this work, promising topologies of adapter-attenuators for HIC with a close to optimal profile of input and output contacts are proposed, which allow not only to obtain a wide range of transformation coefficients (more than 100), but also to reduce the maximum values of the potential gradient and power density by 10‒30 times. The rectangular topology calculations were made using the apparatus of the theory of functions of a complex variable. Modeling of the optimized topology of adapter-attenuators for HIC was carried out by the finite element method implemented in the Elcut software package. The calculated ratios and graphs showing the relationship of attenuation, the transformation coefficient, the gain in the value of the potential gradient and the power density, depending on the ratio of the size of the film element and the resistivity of the resistive films used, have been provided. The features of adapter-attenuators fitting have been considered. The results obtained are especially important for the pulse mode of operation of adapter-attenuators’ film element for HIC.

Design of Robust Quantizers for Low-Bit Analog-to-Digital Converters for Gaussian Source

2019 ◽  
Vol 28 (supp01) ◽  
pp. 1940002 ◽  
Author(s):  
Milan R. Dinčić ◽  
Zoran H. Perić ◽  
Dragan B. Denić ◽  
Zoran Stamenković
Keyword(s):  
Energy Consumption ◽  
Communication Systems ◽  
Mimo Systems ◽  
Automatic Gain Control ◽  
Gain Control ◽  
Analog To Digital Converters ◽  
Signal Power ◽  
Analog To Digital ◽  
Wide Range ◽  
Gaussian Source

This paper considers the design of robust logarithmic [Formula: see text]-law companding quantizers for the use in analog-to-digital converters (ADCs) in communication system receivers. The quantizers are designed for signals with the Gaussian distribution, since signals at the receivers of communication systems can be very well modeled by this type of distribution. Furthermore, linearization of the logarithmic [Formula: see text]-law companding function is performed to simplify hardware implementation of the quantizers. In order to reduce energy consumption, low-resolution quantizers are considered (up to 5 bits per sample). The main advantage of these quantizers is high robustness — they can provide approximately constant SNR in a wide range of signal power (this is very important since the signal power at receivers can vary in wide range, due to fading and other transmission effects). Using the logarithmic [Formula: see text]-law companding quantizers there is no need for using automatic gain control (AGC), which reduces the implementation complexity and increases the speed of the ADCs due to the absence of AGC delay. Numerical results show that the proposed model achieves good performances, better than a uniform quantizer, especially in a wide range of signal power. The proposed low-bit ADCs can be used in MIMO and 5G massive MIMO systems, where due to very high operating frequencies and a large number of receiving channels (and consequently a large number of ADCs), the reduction of ADC complexity and energy consumption becomes a significant goal.

scholarly journals DEVELOPING SOLUTION FOR USING ARTIFICIAL INTELLIGENCE TO OBTAIN MORE ACCURATE RESULTS OF THE BASIC PARAMETERS OF RADIO SIGNAL PROPAGATION

2021 ◽  
Vol 11 (1) ◽  
pp. 36-39
Author(s):  
Andrii Shchepak ◽  
Volodimir Parkhomenko ◽  
Vyacheslav Parkhomenko
Keyword(s):  
Artificial Intelligence ◽  
Radio Signal ◽  
Signal Propagation ◽  
Signal Power ◽  
Signal Source ◽  
Calculation Methods ◽  
Factors Influencing ◽  
Basic Parameters ◽  
Main Factors

The article considers the methods of calculating radio signal power. The main factors influencing the distribution and their connection with the error in the calculations of the indicators' peak values are analyzed. The regularities of signal propagation and the correlation between the distance from the radio signal source and the ratio of noise to useful information are determined. These patterns allow us to develop a model of artificial intelligence, which improves the prediction of results compared to existing calculation methods. The obtained results present the efficiency of the offered method.  

scholarly journals Investigating Predictive Capabilities of RBFNN, MLPNN and GRNN Models for LTE Cellular Network Radio Signal Power Datasets

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Joseph Isabona ◽  
Anthony I Osaigbovo
Keyword(s):  
Neural Network ◽  
Cellular Network ◽  
Radio Signal ◽  
Network Models ◽  
General Regression Neural Network ◽  
Signal Power ◽  
Neural Network Models ◽  
The Neural Network ◽  
Radio Signals ◽  
General Regression

Efficient radio frequency signal coverage planning with well configured transmitters and receivers’ communication channels, is the heart of any cost-effective cellular network design, deployment and operation. It ensures that both network quality and coverage are simultaneously make best use of (i.e. maximized). This work aim to appraise the adaptive learning and predictive capacity of three neural network models on spatial radio signal power datasets obtained from commercial LTE cellular networks. The neural network models are radial basis function neural network (RBFNN), multilayer perceptron neural network (MLPNN) trained with Bayesian regulation algorithms and general regression neural network (GRNN) models.  Largely, it is established from the results that ANN prediction methods can tolerate and adapt to measurement errors of attenuating LTE radio signals. Performance comparisons reveal that all the neural network models can predict the propagated LTE radio signals with considerable errors. Specifically, RBFNN delivered the overall best performance with the smallest mean absolute percentage error, root mean square error, mean absolute error and standard deviation values. The GRNN model also gave better prediction results with marginal errors compared to the MLPNN. Thus, the predictive abilities of RBFNN and GRNN models can be explored as a useful tool to successfully plan or fine-tune mobile radio signal coverage area. Keywords: Neural networks; Signal power; attenuating radio signals; radial basis function multilayer perceptron, general regression neural network, Adaptive signal prediction

scholarly journals Redistribution of Signals Power in Multipath System of Radio Communication

2019 ◽  
Vol 7 (4) ◽  
pp. 54-59
Author(s):  
W. I. Kaganov ◽  
F. Ki
Keyword(s):  
Communication Systems ◽  
Radio Signal ◽  
Scattering Matrix ◽  
Signal Power ◽  
Radio Communication ◽  
Microwave Transistor ◽  
Single Beam ◽  
Microwave Signals

Two types of satellite radio of communication systems are compared: single-beam and multibeam. The problem of summation and redistribution of radio signal powers of communication systems is discussed. The power redistribution of a group of microwave transistor amplifiers between different beams is analyzed. An adder circuit based on bridge quadrature devices is considered in two- and four-ray systems. For two such cases, the scattering matrix of the signal power adder was compiled. On the basis of these two cases it is possible to compose a scattering matrix for the number of summed powers of microwave signals with the number of rays equal to 8, 16 and 32.

Recent Applications of High Resolution Electron Microscopy to Crystalline Arrays of Virus Particles

1978 ◽  
Vol 36 (3) ◽  
pp. 470-482 ◽  
Author(s):  
R.W. Horne
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Analytical Techniques ◽  
Staining Technique ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
Full Potential ◽  
Virus Particles ◽  
Resolution Electron ◽  
Wide Range

The technique of surrounding virus particles with a neutralised electron dense stain was described at the Fourth International Congress on Electron Microscopy, Berlin 1958 (see Home & Brenner, 1960, p. 625). For many years the negative staining technique in one form or another, has been applied to a wide range of biological materials. However, the full potential of the method has only recently been explored following the development and applications of optical diffraction and computer image analytical techniques to electron micrographs (cf. De Hosier & Klug, 1968; Markham 1968; Crowther et al., 1970; Home & Markham, 1973; Klug & Berger, 1974; Crowther & Klug, 1975). These image processing procedures have allowed a more precise and quantitative approach to be made concerning the interpretation, measurement and reconstruction of repeating features in certain biological systems.

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Application of TEM to Deformation, Wear, and Fracture of Ceramics

1974 ◽  
Vol 32 ◽  
pp. 472-473
Author(s):  
B. J. Hockey
Keyword(s):  
Wear Resistance ◽  
High Temperature ◽  
Mechanical Behavior ◽  
Brittle Materials ◽  
High Temperature Strength ◽  
Wide Range ◽  
Corrosive Environments ◽  
Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

Sign in / Sign up

Export Citation Format

Share Document