2008, volume 13, № 3
The complex shaped Cavity axially symmetric resonators: The numerical algorithm for eigenfrequency spectrum calculation
A. Y. Popkov, A. Ye. Poedinchuk, I. K. Kuzmichev
473-480
Bubnov-Galerkin method is applied for calculation axially symmetrical types of electromagnetic field oscillations for cavity rotational symmetry resonators with infinite conductivity boundaries. The problems of algorithm convergence and stability when the number of the basics functions in Bubnov-Galerkin method increases are considered. The general algorithm abilities is analyzed with spherical shape resonator. The eigenfrequency spectrums for resonators constructed by spherical, cone and cylindrical shaped surfaces is examined. The oscillations with existence of caustic which is typical for quasi-optical resonators with spherical shaped reflectors are found.
RESONANT PROPERTIES OF PLANAR DIELECTRIC WAVEGUIDE – LAMELLAR GRATING SYSTEM
V. V. Kryzhanovskiy, S. V. Kryzhanovskiy, S. O. Steshenko, O. V. Chistyakova
481-488
The resonant properties of planar dielectric waveguide – lamellar grating system have been investigated numerically. The classification of different kinds of resonances, which appear with a change of the system parameters including the groove sizes, the dielectric waveguide thickness and the distance between the waveguide and the grating, is accomplished. Some practically useful recommendations regarding the choice of the waveguide and grating parameters in antennas applications are given.
ELECTRICALLY SWITCHABLE, KA-BAND SLOTTED WAVEGUIDE ANTENNA ARRAY SYSTEM
S. S. Sekretarov, D. M. Vavriv, V. A. Volkov, M. P. Natarov, V. V. Glamazdin
489-493
An original electrically switchable, Ka-band slotted waveguide antenna array system has been recently developed, produced, and tested. The system consists of four identical sections, which are connected to a radar transmitter/receiver by means of a high-power, multipole p-i-n switch. The introduced p-i-n switch enables for a fast electrical scanning of the antenna beam what essentially extends possible areas of the antenna system application. The antenna system is used in a helicopter collision avoidance, surveillance, and weather radar. This paper describes design features of the antenna system, its main characteristics, results of its testing, and the antenna integration in the radar.
THE DIFFRACTION MODEL OF RADIOWAVE PROPAGATION IN ELEVATION MEASUREMENT OF TRANSMITTER
V. B. Razskazovskyy, Yu. F. Logvinov
494-502
The elevation measuring of microwave transmitter above the sea surface with wind waves at small grazing angles and low altitudes have been studied in multiple Fresnel diffraction approach by means of numerical methods. It is shown that this model conforms to experimental data on measuring the elevation of transmitter at altitudes comparable to the sea wave height.
INSTRUMENTAL ERRORS OF INTERFEROMETRICAL METHOD OF RESERCH ON TROPOSPHERIC REFRACTION ON PATH GEO SATELLITE – EARTH
D. D. Khalameyda
503-511
Possibility of using interferometer receiving radio signals of Geostationary Satellite for measuring tropospheric refraction index is discussed. For this reason exponential model of troposphere is used. Factors decreasing the accuracy of measuring of arrival angle, such as receiver noise, instability of antenna phase center location, variation of properties of feeder tract, are shown. Demands for different characteristics of interferometer are discussed.
New Parameters for the Ultra-Wideband SignalS and ProcessES DescriPTION
O. V. Lazorenko
512-517
The possibility of distinguishing of the ultra-wideband (UWB) signals from frequency modulated (FM) signals is considered. It is demonstrated that FM signal, being narrowband in each instant of time, with the traditional UWB signal definition usage can be falsely classified as the UWB signal. The dynamic fractional bandwidth conception based on the analysis of the spectral density function of short-time Fourier transform is suggested. The efficiency of the new criterion based on this conception for FM signal analysis is shown.
RESONANCE TUNNELLING DIODES ON AlN/AlxGa1-xN, GaN/InxGa1-xN
О. V. Botsula, E. D. Prokhorov, I. P. Bezmal
518-522
Resonance tunnelling diodes (RTD) on the base nitrides AlN, GaN, InN have being investigated. Сurrent-voltage characteristics of RTD with five energy levels were calculated. The current-voltage characteristics RTD was demonstrade to have five negative resistance region. The possible oscillation efficiencies for all negative resistance region was determined.The estimation of maximal oscillation frequency for each negative resistance region has been determined.
ALGORITHM OF SOLUTION OF EQUATIONS OF DIFFUSIVE-DRIFTING MODEL OF SEMICONDUCTORS STRUCTURES WITH AVALANCHE P-N JUNCTIONS
P. P. Maksymov
523-528
The algorithm of solution of equations of diffusive-drifting model of the back biased pn-i-pn structures with abrupt p-n junctions has been developed. As a basis of the algorithm the following difference equations were taken: equation of modified method of the meeting drive away, equation of computing method of semiconductor pn-i-pn structures with abrupt p-n transitions and equation of computing method of abrupt p-n transitions in self-oscillation mode. Inaccuracy of calculating the electric field of Ge, Si and GaAs pn-i-pn structures with a feed-back is appraised. It is shown that a relative error diminishes with the increase of number of knots of difference net and limited by the error of approximation of differential operators difference. Self-oscillations of the electric field, density of current, and their spectrum and phase portrait are given.
MODELING OF SHF MIXERS ON THE BASIS OF ABRUPT P-N JUNCTIONS
P. P. Maksymov
529-534
The mixer of SHF signals is designed on the basis of abrupt avalanche Ge, Si and GaAs p-n junctions. As a mathematical model the equations of diffusive-drifting model (DDM) of semiconductors are used. The solution of equations of DDM is the modified method of the meeting driving away. The principle of mixer operation is considered. Physical nature of signal distortions is determined. An amplification factor, amplitude and frequency responses, have been calculated. The spectrum of frequencies and phases of output signal of Ge, Si and GaAs p-n junctions have been given.
MULTI-MODE OSCILLATIONS IN DRO
K. A. Lukin, E. M. Khutoryan, A. I. Tsvyk
535-545
The theory of oscillations in DRO with open resonator having fundamental and higher modes with close frequencies has been considered. The stationary and transient regimes have been studied. The solution describing the stable two-mode oscillations during electron beam interaction with fundamental and higher modes has been obtained. The physical features of interaction of electron beam with mode fields of DRO open resonator have been studied using large particles ensemble phase plane. The obtained results have been compared with experiment.
SELF-MIXING GUNN DIODE TRANSCEIVER WITH INTERNAL DETECTION FOR A SHORT-RANGE RADAR SENSOR WITH LINEAR FREQUENCY MODULATION
A. V. Varavin, A. S. Vasilev, G. P. Ermak, I. V. Popov
546-551
The work presents the results of a research on an 8-mm self-mixing transceiver for a short-range FMCW radar sensor with linear frequency modulation, designed for measuring distance and target’s speed. The self-heterodyne transceiver is built on a Gunn diode with varactor frequency tuning. Internal detection is performed using a current sensor in the supply chain of the Gunn diode. Realized are the methods of digital signal generation, spectral processing and digital filtering.
THE STUDY OF QUASI-OPTICAL POLARIZATION FREQUENCY CHANGER WITH ROTATING LINEAR POLARIZER
V. I. Bezborodov, V. K. Kiseliov, Ye. M. Kuleshov, V. N. Polupanov, M. S. Yanovsky
552-555
The design and principle of operation of quasi-optical polarization frequency changer with rotating linear polarizer have been described. The level of unwanted oscillations of input signal frequency and "mirror" frequency at the output was less than –50 dB relative to wanted signal level when tuning the quarter-wave differencial phase sections in operating frequency.
Function of UHF-Radiation in Increasing of the Blood Activation
O. I. Belous, B. G. Yemets, V. A. Malakhov, A. V. Nosatov, S. P. Sirenko, A. I. Fisun, Ye. B. Almazova
556-561
The paper is devoted to use the human blood exposure to UHF-radiation for treatment of the brain circulation disorder. A cylindrical high-mode cavity resonator serves as irradiator of the blood dose of some 20 ml at the 7,1 mm wavelength. The high-mode excitation is associated with uniform field distribution at the blood – dielectric interface. There are observed an upgrading of neurological status of patients, a trombocite aggregation comes to decrease, and an antioxidant system makes more active as well. Interpretation of the blood activation is discussed.
AUTOMATED scanning ESR-MICROSKOPE FOR INVESTIGATION OF MAGNETIC INHOMOGENEITY OF LOW-PROFILE NANOSTRUCTURE
A. V. Varavin, G. P. Ermak, M. I. Nahimovich, I. V. Popov, S. I. Tarapov, B. A. Avramenko, A. G. Ravlik, V. N. Samofalov
562-567
The design and experimental investigation of the automated scanning ESR- microscope, which is able to detect magnetic inhomogeneity of low-profile magnets and ferromagnets by the method of Electron Spin Resonance (ESR) in 30-45 GHz frequency band is presented. The strong static magnetic field in the working zone of the microscope is created by the use of the special magnetic field concentrator unit. Mechanical shifting of the specimen provides the scanning of the static magnetic field on its surface. The first experimental data, which demonstrate the efficiency of the device operation, are presented and analyzed.
DEVELOPMENT OF TEST-SYSTEMS FOR INVESTIGATION OF VARIOUS TYPES OF ELECTROMAGNETIC RADIATION ON BIOLOGICAL OBJECTS
T. Yu. Shchegoleva , E. M. Gromozova, S. L. Vojchuk, N. V. Bryuzginova, B. R. Masyuk, P. S. Krasov
568-571
The data on changes of hydrated encirclements of the yeast culture were taken by means of EHF dielectrometry method. The effects of electromagnetic radiation of different intensities and various nature on the yeast culture were studied. Possibilities of using cell cultures as sensors for investigation of such influences were shown.
CONCEPT OF PLANETARY THERMAL BALANCE AND GLOBAL WARMING
A. P. Nickolaenko
572-576
The concept of Earth’s thermal balance is used suggesting that the solar irradiance absorbed by the planet is equal to the thermal radiation from the Earth. Such an approach allows for evading the energy transform from one type to another and from one frequency band to another one. Intensity of solar heating is then compared with the antropogenic heat production from different kinds of fuel. It is shown that heat produced by the mankind is quite sufficient for raising the median planetary temperature by approximately 1 centigrade per century. Thus, a new possible cause is named that might be responsible for the global warming.