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The method of calculation of hybrid waves in a waveguide was obtained taking into account the interaction of waves of TE and TM types in a cylindrical coordinate system. The calculation of the electric field vector for the fundamental mode, as well as for hybrid modes depending on the radial coordinate of symmetric inhomogeneous multimode fibers with different profiles of dielectric permittivity of...
The present paper concerns the activity of the microbic biofuel element which oxidizes ethanol. The intact bacterial cells of Gluconobacter oxydans or their membrane fractions were used as a bioelectrocatalyst. Thermoexpanded graphite (TEG) was used as a material of an electrode. The used strain of bacterial cells, as well as carbon composition types will make a basis of a prototype of a microbic...
The possibility of supramolecular organization modeling of a cholesteric liquid crystalline (ChLC) matrix was shown by molecular dynamics simulation using the all-atom model. The supramolecular organization of ChLC mesogen and ChLC - a single walled carbon nanotube composite was estimated and 3D-model of a cholesteric phase of the studied compound was obtained. The effect of a carbon nanotube on the...
The present paper concerns the study of the distribution of time intervals between packets of inbound and outbound user access. The quantitative estimations of obtained distributions are given and the possibility of using the results for the calculation of the modern telecommunication networks is described.
Correlation is one of the most significant DSP procedures in modern correlation extreme navigation systems based on measurements of geophysical fields parameters. The main subject of this paper is an optimal implementation of correlation by means of function-oriented processors (FOP) based on 2D processor element arrays. Real FOP's based on universal microprocessors are considered as well.
The principle of the hybrid frequency synthesizer performed on the basis of a phase-locked loop and direct digital synthesizer is considered. The synthesizer uses images of the fundamental frequency and performs a frequency conversion with a mixer in the feedback path. The mathematical expressions for the model of power spectral density of the phase noise of the synthesizer are obtained. The results...
The frequency receiving-converting unit operating on two parallel channels with intermediate frequencies of 144.0??? 176.0 MHz and 100???1100 MHz is experimentally studied. The present paper concerns the details of the receiving-converting unit's modeling. Modeling was carried out with the aim of visual confirmation of the correct choice of software package.
The present paper concerns the digital radio relay station with 820 Mbit/s bandwidth and with an emission band of 80 MHz. Such stations are manufactured by ???Beta TV com???, Ltd, Donetsk, Ukraine.
The problem of visibility improvement by means of television image processing is considered. Two main approaches to enhancement of images, recorded in adverse weather, are analyzed. As an example of model-based method the dark channel prior method was chosen. Its results are compared with results of nonlinear contrast enhancement methods. The modification of adaptive histogram equalization that supposes...
Development of the L1 range band passing filter (BPF) is presented in the article for GPS signal. Design of BPF is carried out with Nuhertz Filter software use, with the subsequent simulation in the Microwave Office program.
The present paper suggests a method of external modulation by an optical modulator of laser. Permissible speed of a modulating signal of Corning-10-A modulator is 10.5 Gbit/s and overall speed of all service signals is 4G in Interactive Heterodyne Transport Network (for 2000 kinds of service, 12 Mbit/s for each service) is 24 Gbit/s in total. This contradiction can be solved by application of the...
The present paper concerns a comparison of different methods for calculation of the apparent center of a distributed target to create an echo signal simulator. A quantitative analysis of the apparent center fluctuations due to phase shift signals from the individual elements and due to changes of the scan angle, is carried out.
Theoretical possibilities of increasing capacity of a single-interval radio relay line by means of the physical phenomenon of phase front curvature of electromagnetic waves are presented. Location of repeaters of radio relay stations (RRS) in Fresnel zone is the main condition. The scheme for implementation of this method and results of modeling distances (bases) up to additional antennas of repeaters...
Applying the PLL system as a multiplier of direct digital synthesizers (DDS) output frequency in hybrid frequency synthesizers was analyzed in this paper. Increasing of DDS output frequency helps to reduce the division ratio in the feedback loop and, as consequence, decrease the phase noise level. It was proved that the PLL multiplier makes a significant contribution to the phase noise level of the...
The technical solution of an analog-to-digital converter consisting of two ADC chips ADS54RF63 is proposed. It makes possible to process the input signal bandwidth of 0.5 GHz with dynamic range of 60 dB. This analog-to-digital converter is produced by Beta TV com Ltd, Donetsk, Ukraine.
The possibility of submillimeter orotron with double-row periodic structure development is considered. Results of experimental investigation of a model of such device with 0.182-mm periodic structure step and different modifications of open resonators in 140???360GHz frequency range are presented.
The results of the optimization search using an elaborated mathematical model for the promising versions of a klynoorbictron-amplifier design to be operated over the frequency range of 180 GHz are presented. The versions of the devices have been found, which are capable of providing from 10 to 14 % efficiency, the gain of 18???38 dB, the output power of 10 to 40 W with input signal power of 0.01???0...
The results of experimental research of dispersion characteristics of a coupled cavity chain with single and periodic discontinuities are presented. The connection between the magnitude of displacement of band components dispersion characteristics of a non-uniform system relatively a uniform system dispersion and stopband width between them from the type, size and number discontinuities is established.
Errors of altimetric a wind speed determination, which are caused by variability of thin topographical structure of the sea surface physically not connected with variations of a wind speed, are considered. It is shown, that in case of light and moderate wind the main contribution to an error is given by variations of energy of short surface waves, at high wind speeds it is given by uncorrelated with...
The paper analyzes the identification results of underflooding manifestations on vegetated soil as per consecutive day-time and night-time and multi-seasonal radar-thermal IR aviation complex ACRS-30 of remote sensing. The investigations were carried out in winter and dry autumn season conditions, when the vegetation processes in crops are mostly stopped.
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