JournalTOCs

Journal of Communications Technology and Electronics
Journal Prestige (SJR): 0.273

Citation Impact (citeScore): 1
Number of Followers: 2

Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1555-6557 - ISSN (Online) 1064-2269
Published by Springer-Verlag

[2626 journals]

Ray Pattern of Pulsed Wave Field Metaparticles
- Abstract: The study estimates distance at which the effective transverse size of a field of metaparticle directionally radiated by an aperture source is preserved in order of magnitude during as metaparticles propagate from the aperture. Thus, the ray pattern of the radiation field of metaparticles is preserved.
  PubDate: 2020-07-01
Low Complexity Method for Recovering Continuous Phase Modulation Signals
with Low Signal-to-noise Ratios
- Abstract: A low computational complexity scheme based on the modified Wigner–Ville distribution (MWVD) is developed for estimating the instantaneous frequency of continuous phase modulation (CPM) signals under low signal-to-noise ratio (SNR) scenario. To simplify the computation of the MWVD, a low order Chebyshev polynomial is chosen as the kernel function for suppressing the cross-terms. The implementation of this instantaneous frequency (IF) estimator is done through the Viterbi algorithm. The simulation results show that our scheme outperforms other estimating methods under low SNR scenario.
  PubDate: 2020-07-01
Artificial Dielectric Based on Conducting Squares with Resistive Jumpers
- Abstract: In this paper, we calculate the dispersion of the effective dielectric constant of the structure from the lattice of conductive squares located in a dielectric layer and connected by resistive jumpers based on the solution of the diffraction problem. Depending on the parameters of the jumpers , the dispersion of this structure was shown to be capable of varying from the relaxation type to one that corresponds to the structure of continuous resistive films. The jumpers were also shown to affect the nature of the dispersion in the long-wave part of the wave range most significantly in relation to the structure period.
  PubDate: 2020-07-01
Charge Trajectories in a Cylindrical Beam with Allowance for Variable
Magnetic Induction and Vortex Electric Fields
- Abstract: The study analyzes trajectories in a cylindrical beam taking into account variable magnetic induction and vortex electric fields. It is shown that the inclusion of vortex fields during simulation stabilizes a trajectory.
  PubDate: 2020-07-01
Nature of Currents Induced by Changes to the Sample Parameters.
Capacitance and Noncapacitance Currents
- Abstract: In developing the ideas of the Ramo theorem, paper considers the nature of currents in an external circuit arising when the sample parameters are changed. It is shown that, besides currents induced by charge movement in the sample and capacitance currents, other currents are possible. Formulas and an illustrative example are presented, in which there are currents in the external circuit when the structure parameters are changed, although there are no capacitance currents or currents induced by charge movement.
  PubDate: 2020-07-01
Enhancing the Efficiency of the Reconstruction of the Temperature and
Humidity Profiles of the Cloud Atmosphere by the Data of Satellite
Microwave Spectrometers
- Abstract: It is shown that the a priori data on the atmospheric conditions, in addition to the climate’s characteristics, can enhance the efficiency of the algorithms for reconstructing the atmospheric profiles using satellite microwave radiometric observations. Such additional data are sought and their efficiency in remote sensing is estimated. The possibility of expanding the statistical approach by including new types of a priori data on the temperature and humidity of atmospheric conditions is discussed. It is demonstrated that the developed technique can be used to estimate the efficiency of using the following types of additional a priori data in the statistical regularization method: (i) the covariance matrix of the full vector of temperature and humidity variations within a vertical atmospheric column, (ii) the covariance matrix of the temperature and humidity variations within horizontal atmospheric strata, (iii) physical limits of the humidity variation amplitude, and (iv) statistically average model representations of the microwave radiation transfer parameters in the cloud layer.
  PubDate: 2020-07-01
Analysis of Dynamic Processes in Biological Systems Using Acousto-Optic
Video Spectrometry
- Abstract: A measurement setup based on a transmission microscope with double acousto-optical wavelength selection is proposed for detection of high-quality spectral images with a size of 1920 × 1200 pixels in the visible wavelength range with a spectral resolution of 2.5 nm at a wavelength of 632 nm. The efficiency of the proposed approach and setup is demonstrated in the study of the transition of Misgurnus fossilis embryos from the 32nd to the 33rd stage. Correctness of the conclusions is proven in a comparison with the results of the corresponding ultrasonic study. Analysis of time dependences of the transmission spectra is performed for six spatial regions of the embryo including perivitelline space and head and tail sections. Such substantially different dependences can be used, in particular, for noninvasive monitoring and analysis of changes in the functional state of embryos related to the stage-to-stage transition.
  PubDate: 2020-07-01
Mathematical Model for the Separation of an Elliptically Polarized Wave in
Anisotropic Photonic Crystals into TE - and TM -Waves
- Abstract: A one-dimensional anisotropic photonic crystal is considered. A mathematical model is constructed that separates an elliptical polarization wave into TE- and TM-type waves. The transformation matrix is found for a periodic structure with an arbitrary number of layers in a period in the form of a block diagonal matrix. The transformation matrix is found for an arbitrary number of periods of the structure with anisotropic layers. Dispersion relations are found that determine the boundaries of the allowed zones.
  PubDate: 2020-07-01
Recognition of Anthropogenic 3D Objects on an Underlying Surface by
Intelligent Analysis of a Polarization Scattering Matrix
- Abstract: This paper proposes a technique for recognizing anthropogenic location objects on an underlying surface that is based on measuring the complete polarization scattering matrix (PSM) of a radiolocation scene. The intelligent analysis of a PSM implies the generation of adaptive robust estimates for trends and covariance matrices, as well as reflected non-stationary non-Gaussian signals. Based on the results of the digital computer simulation experiments and field measurements of the radiolocation scene’s PSM, machine learning algorithms for clustering and classifying the elements of an underlying surface and location object are verified. The possibility of using neural network architecture in the form of a support vector machine for real-time implementation of these algorithms is substantiated.
  PubDate: 2020-07-01
Reliability Evaluation Method for DVB-T2 Systems on Typical Transmitter
Stations
- Abstract: In this paper, we model the Digital Video Broadcasting-Terrestrial 2 (DVB-T2) system on a typical transmitter station in the content regionalization mode by using multilayer graphs to evaluate its reliability parameters. One of the proposed models characterizes the states of the broadcasting system when using only local content insertion in accordance with ETSI TS 102773. The second model, also implemented as a multilayer graph, describes the states of the system when the regionalization devices are cascaded. Based on the proposed expressions for the probability of 100% uptime operation of each broadcasting system, their parameters are evaluated, showing that the system with cascade content insertion has an availability factor that is 3.28% higher than that of the system with content insertion based on physical layer pipe (PLP) replacement, with the direct reservation of the cascade scheme improving its reliability by 9.77%.
  PubDate: 2020-07-01
Analytical Method for Studying an Extraordinary Wave in a One-Dimensional
Anisotropic Photonic Crystal
- Abstract: The behavior of an extraordinary wave in a layered uniaxial anisotropic medium is reviewed. The transformation matrix is found for a homogeneous layer and for a multilayer structure with an arbitrary number of layers in an analytical form in elementary functions. The concept of partial waves in a layered medium and their contribution coefficients for an extraordinary wave is introduced. It is shown that the reflection and transmission coefficients of an extraordinary wave for a plane-parallel plate are equal to the sum of the reflection and transmission coefficients of partial waves.
  PubDate: 2020-07-01
Building Systems for Object Recognition by Multichannel Sensing Systems
Based on Neural Networks and Fractal Signatures
- Abstract: An approach to building a multichannel pattern-recognition system by sensing systems is proposed. A list of problems solved by the sensing systems in the construction of object-recognition systems is specified. The problem of image preprocessing is formulated in the form of an ill-posed problem. The value of the fractal dimension D (the fractal signature) of images of contours of objects is used to create an additional characteristic. The methods for solving the problems of building modern object-recognition systems are evaluated.
  PubDate: 2020-07-01
Solution of the Problem of Diffraction by a Plane Screen in a Plane
Layered Medium with the Help of the Method of Continued Boundary
Conditions
- Abstract: The 3D problem of diffraction of the field of a point source by a plane screen located on the interface of a plane layered medium is considered. The algorithm of the numerical solution of this problem is developed on the basis of the method of continued boundary conditions. In particular, the case, when the screen is located on the interface between two media and on the upper boundary of a dielectric layer surrounded by identical dielectric half-spaces, is considered. The correctness of the obtained results is controlled by verifying the accuracy of the fulfillment of the optical theorem. The angular dependences of the scattering pattern are constructed for the screens having circular, rectangular, and elliptic shapes.
  PubDate: 2020-07-01
Tunable Acousto-Optic Filter for the 450–900 and 900–1700 nm
Spectral Range
- Abstract: The problem of creating an acousto-optic (AO) tunable filter, which allows us to obtain high-quality spectral images both in the visible and near-infrared ranges, is studied. Based on the analysis of the wide-aperture noncollinear geometry of AO diffraction in paratellurite, the AO cell configuration is determined that is optimal in terms of minimizing chromatic shift and is suitable for both ranges. Two identical cells are manufactured and matched for the ranges 450–900 and 900–1700 nm. Experimental verification of the results of optical modeling showed that, over the entire range of 450 to 1700 nm, the calculated AO filter provides high-quality spectral images.
  PubDate: 2020-07-01
Blood Vessel Visualization Method in Human Skin Based on Video Recording
of Blood Flow Using a Laparoscope
- Abstract: The possibility of increasing the reliability of early diagnoses of diseases associated with a lesion of the capillary network morphology in human skin is considered. A method for visualizing the capillary network of blood vessels in the studied area of the skin is proposed. This method includes a probe optical-electronic system of an original design. A prototype of a probe optical-electronic video capillaroscopy (VCS) system, measurement technique, and data processing methods have been developed to study the parameters of the capillary network. A method that calculates the capillary map in the studied area, based on the analysis of the recorded sequence of video frames of the capillary blood flow is described. The effectiveness of the method is confirmed experimentally by examining the capillary network in the forearm, hands, and nail bed.
  PubDate: 2020-07-01
Analysis of the Modeling Results for Passenger Traffic at an Underground
Station Using AnyLogic
- Abstract: This study is aimed at analyzing incoming passenger traffic using AnyLogic software at a typical underground station in order to examine it for points of congestion.
  PubDate: 2020-06-01
Improving the Quality and Contrast of Image Details Using the Geodesic
Distance Filter
- Abstract: —As a rule, modern methods of improving and contrasting image details are based on the edge-preserving filters or bilateral filters. However, the computational complexity of classic bilateral filters is proportional to the square of the number of pixels in the image and fast algorithms are not always efficient enough or the filtering result does not always match the result of the original filter. We propose replacing the classic bilateral filter with a geodesic distance filter, which also belongs to the class of convolution transformations that can improve visual perception of images using information about the edges of objects in the processed image. The convolution kernel based on the geodesic distance has several advantages, as it allows recursive computation and, therefore, fast image processing. We also propose a method for suppressing color artifacts by switching from the standard RGB representation to the HSV representation, which is more balanced with respect to the perception of human vision. The effectiveness of the proposed filter is compared using the illustrations to this article so that the reader can visually compare the qualities of various processing options.
  PubDate: 2020-06-01
Dynamic Multiplexing of URLLC Traffic and eMBB Traffic in an Uplink Using
Nonorthogonal Multiple Access
- Abstract: —The problem of uplink multiplexing of two different types of traffic specific to 5G networks (enhanced Mobile Broadband traffic (eMBB) and Ultra-Reliable Low-Latency Communications (URLLC)) is considered. A dynamic multiplexing scheme based on the use of the nonorthogonal multiple access is proposed. An analytical model is developed to estimate the network performance using the proposed scheme, as well as to select its optimal parameters in order to maximize the network capacity for eMBB traffic while fulfilling the quality of service requirements for URLLC traffic.
  PubDate: 2020-06-01
Transformation of the Frequency–Phase Response of a Signal Reflected
from a Vibrating Surface
- Abstract: —The structure of a signal reflected from a vibrating surface is studied in the case when the vibration amplitude is comparable to or significantly greater than the wavelength of the probing electromagnetic wave. It is shown that the relations between the amplitudes of the highest harmonics makes it possible to calculate the vibration amplitude in situations when it is longer than the probe wavelength. Criteria are obtained that make it possible to choose the harmonics of the reflected signal to uniquely determine the vibration amplitude. It is shown that the effect of energy redistribution between a large number of harmonics of the reflected signal, which occurs with an increasing phase modulation index, leads to a decrease in their amplitude by about 1.75.
  PubDate: 2020-06-01
Resonance Radar Absorber Matched with Free Space at a Given Frequency
- Abstract: —A resonance radar absorber is proposed that is theoretically matched with the free space for a reflection coefficient level no greater than –40 dB at a given frequency. The design of the absorber is an array of electrically conductive squares on a lossy dielectric layer metallized on the opposite side of the array. A preset dielectric is used in the absorber design, and the dimensions of the square elements of the array are many times greater than the thickness of the dielectric layer. The relative change in the resonance frequency with a change in the angle of incidence of TE- and TM-polarized waves in range of 0°–45° does not exceed 1%.
  PubDate: 2020-06-01