Begell House Inc.
Telecommunications and Radio Engineering
TRE
0040-2508
77
15
2018
SOURCEWISE REPRESENTATION OF THE ELECTRIC GREEN FUNCTION FOR A FIELD OF THE CIRCULAR CAVITY
1297-1309
10.1615/TelecomRadEng.v77.i15.10
S. D.
Prijmenko
National Science Center "Kharkiv Institute of Physics and Technology", Kharkiv, Ukraine
integral equations
singular and hypersingular equations
sourcewise represented function
electric Green function
circular cavity
A singular part of the electric Green function for a field of the circular cavity is singled out in an explicit form as an infinite-space Green function. The problem of construction of the Green function for a field is solved as a problem of the diffraction of tensor divergent spherical and quasi-spherical waves on the circular cavity walls. Analytical expressions for singular and regular parts of the tensor Green function and calculation results obtained for one of its components are presented.
FORMING THE POWERFUL MICROWAVE PULSES USING RESONATOR STORAGE
1311-1319
10.1615/TelecomRadEng.v77.i15.20
I. N.
Bondarenko
Kharkiv National University of Radio Engineering and Electronics, 14, Nauka Ave, Kharkiv, 61166, Ukraine
Е. А.
Gorbenko
Kharkiv National University of Radio Engineering and Electronics,
14, Nauka Ave, Kharkiv, 61166, Ukraine
microwave pulse
resonator storage
tee structure
switch
The storage properties of conventional (uncooled) resonance cavities are evaluated to determine the possibility of their use as electromagnetic energy storage devices. A comparative analysis of the characteristics of switching devices based on structures of a waveguide tee combined waveguide-coaxial type is presented. It is shown the possibility of realization of microwave pulse shapers with the resonator Q-accumulator not less than 103, pump oscillator instability not worse than 10-4 and micron (10...20 m) accuracy of performance of tee structure design and placement of control active elements.
INTELLIGENT ANALYSIS OF RADAR DATA BASED ON FUZZY TRANSFORMS
1321-1329
10.1615/TelecomRadEng.v77.i15.30
S. V.
Solonskaya
Kharkiv National University of Radio Electronics,
14, Nauka Avenue, Kharkiv, 61166, Ukraine
V. V.
Zhirnov
Kharkiv National University of Radio Electronics,
14, Nauka Avenue, Kharkiv, 61166, Ukraine
radar data
fuzzy transform
functional dependence
radar marks
intelligent analysis
It is proposed to use a fuzzy transform apparatus for analysis of the radar data in the form of mark coordinates and their virtual images generated on the basis helpful and interfering signal, which are considered as the fuzzy samples and sets. It is shown how this approach can be used to identify the functional (semantic) dependencies between components of the radar data and images.
A TECHNIQUE FOR MEASURING COORDINATES OF MOVABLE OBJECTS BY VIDEO PULSE RADARS
1331-1343
10.1615/TelecomRadEng.v77.i15.40
Oleg
Sytnik
O.Ya. Usikov Institute for Radio Physics and Electronics, National Academy of Sciences of Ukraine, 12 Academician Proskura St., Kharkiv 61085, Ukraine
Gennadiy P.
Pochanin
O.Ya. Usikov Institute for Radiophysics and Electronics of the National Academy of Science of Ukraine, 12, Academician Proskura St., Kharkiv, 61085, Ukraine
S. A.
Masalov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine 12, Academician Proskura St., Kharkov 61085, Ukraine
V. P.
Ruban
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine, 12, Academician Proskura Str., Kharkiv 61085, Ukraine
P. V.
Kholod
O.Ya. Usikov Institute for Radiophysics and Electronics of the National Academy of Science of Ukraine, 12, Academician Proskura St., Kharkiv, 61085, Ukraine
radar station
ultra-wideband signal
peak-factor
video pulse
algorithm
interlaced samples
spatially-separated receiving system
A measuring system consisting of several spatially-separated receiving sites and a transmitter radiating video pulse signals is analyzed. The aim is to develop an efficient algorithm for processing signals of multi-position monitoring system operating under conditions of correlated noise intended for online detection of movable objects hidden behind optically opaque obstacles. In the system, the hyperbolic (range-difference) technique is used to measure the target coordinates. Because of multiple re-reflections of the sounding signal from the room walls
and indoor objects, the useful signal from a target is not identified by direct methods. For this reason, a procedure of suppression of the interference reflections of the sounding signal has been developed. Accumulation of the signal and elimination of interference noise from it is performed
in real time through subtracting interlaced samples of the observed process from the signals of
each receiving site on the assumption that the displacement of the object during a single scan is small. The magnitude of the signal peak-factor has been selected as a criterion for estimating time delay of the probe signal on the way from the transmitter to a target and from target to each of the receivers. The same criterion is used for rejecting the noise-affected rows in radar images of the target trajectory. A fast algorithm has been developed that, with a comparatively
high signal-to-noise ratio, enables using the signal peak-factor as a criterion for rejecting the noise-affected rows in radar images and performing continuous processing of the observing system signals with representation in a user-friendly form. The continuity of measuring time
delays of the signals propagating from a target to each of the receiving sites is provided by a polynomial approximation of the object motion trajectory. The high power characteristics of the
monitoring system, stability of its parameters during measurement sessions and high accuracy of reproducing the reflected signal waveform have made it possible to use methods of digital signal processing in real time. The results of simulations are supported by the data that were accumulated and averaged over series of similar experiments.
ON THE INFLUENCE OF THE SHAPE OF ANODE VOLTAGE PULSE ON THE OPERATION STABILITY OF SPATIAL- HARMONIC MAGNETRON WITH COLD SECONDARY-EMISSION CATHODE
1345-1355
10.1615/TelecomRadEng.v77.i15.50
V. A.
Markov
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4 Mystetstv St., Kharkiv 61002, Ukraine
V. D.
Naumenko
Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4 Mystetstv St., Kharkiv 61002, Ukraine
magnetron
spatial harmonic
auxiliary cathode
cold cathode
voltage modulator pulse shape
One of the main problems faced by developers of modulators for spatial-harmonic magnetrons with the cold secondary-emission cathode is the selection of the correct shape of an anode voltage pulse that will ensure the stable operation of the magnetron. In this paper, the effect of a
shape of the anode voltage pulse on the operation of transmitters based on magnetrons with cold secondary-emission cathodes is investigated. It was experimentally studied the influence of different parts of the pulse on such magnetron's parameters as a start cathode current required for stable excitation of cold cathode secondary emission, the stability of operation on the selected mode, and the generation of the maximum power. It is shown that the magnitude of the initial
cathode current is primarily determined by the wavefront steepness. Its optimum value is usually about 150 kV/μ;s. In this case, starting cathode should provide a current of only a few tens of milliamperes, which can significantly increase the device lifetime. The article also shows that the presence of a pulse spike at the beginning of a voltage pulse promotes the premature
transition to a non-operable mode. As a result, this leads to a decrease in the output power of the magnetron. The duration of the decay determines the ability of the magnetron to operate at short pulse duration. For very short pulses, the energy expended on the microwave generation can be equal to the energy expended on the formation of the pulse decay. As a result, it was concluded that the usage of spatial-harmonic magnetrons with cold cathode requires a careful refinement of the characteristics of a pulse modulator. The steepness of the front of its output pulse should be about 150 kV/μ;s and the pulse spike at the beginning of voltage pulse should be as low as possible. When operating at very short pulses it is necessary to provide a longer rate of pulse decay.
SYSTEM OF AUTOMATIC FREQUENCY CONTROL OF HETERODYNE OF THE RADAR RECEIVER WITH MAGNETRON TRANSMITTER
1357-1363
10.1615/TelecomRadEng.v77.i15.60
I. M.
Mytsenko
O.Ya. Usikov Institute for Radiophysics and Electronics of the National Academy of Sciences of Ukraine, 12, Academician Proskura St., Kharkiv 61085, Ukraine
D. D.
Khalameyda
O.Ya. Usikov Institute for Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura St., Kharkiv 61085, Ukraine
radar
magnetron transmitter
automatic frequency control
discriminator
At present, pulsed magnetrons are leaders in the use in the radar transmitters which is caused by the need to generate powerful high-frequency oscillations and to provide a given coverage range. The disadvantages of magnetrons include a significant level of noise and difficulties in implementing frequency control. For this reason, when using automatic frequency control (AFC), problems arise in controlling the frequency of the pulsed magnetron. In view of this, the AFC of heterodyne of the receiver rather than the one of the magnetron is most often used. The heterodyne frequency is maintained such that the receiver is always tuned to the frequency of the received signal. The objective of this paper is to analyze the existing methods for tuning the heterodyne frequency of pulsed radars with a magnetron transmitter, to develop a concept for building a functional layout and its practical implementation. The functional layout of the automatic frequency tuning system of heterodyne in radar receiver with a magnetron transmitter is developed and described in the paper. A frequency discriminator is used in AFC. The frequency discriminator combines the advantages of a single-cycle circuit (simplicity of design and tuning) and a two-cycle circuit (an output voltage equal to zero at the given magnetron frequency, as well as compensation of variations in the amplitude of the input voltage and interference). The practical implementation of the developed system is presented upon the example of millimeter-wave band radar (40 GHz), where a Gunn diode oscillator with varactor frequency tuning is used as the receiver heterodyne oscillator. In this paper, the electric scheme of a new frequency discriminator and its amplitude-frequency characteristic are shown. An intuitive method was used to develop an electrical schematic diagram. The analysis of the developed scheme was carried out using the method of mathematical modeling. Conclusions are drawn about the novelty of the proposed concept of constructing the AFC of heterodyne radar receivers with a magnetron transmitter and its advantages in comparison with known solutions.
NOVEL COAXIAL CABLE IMPLEMENTATION OF MINIATURIZED WILKINSON POWER DIVIDER AND QUADRATURE HYBRID COUPLER FOR VHF APPLICATIONS
1365-1374
10.1615/TelecomRadEng.v77.i15.70
Makarand
Kulkarni
K.J. Somaiya College of Engineering, Vidyavihar, Mumbai- 400077, India and Research Scholar of Dept. of Electrical Engineering, Veermata Jijabai Technological Institute (VJTI),H. R. Mahajani Marg, Matunga, Mumbai-400019, India
A.
Cheeran
Department of Electrical Engineering, Veermata Jijabai Technological
Institute, HR Mahajani Marg, Matunga, Mumbai-400031, Maharashtra,
India
K.
Ray
Dept. of Electronics Engineering, Defense Institute of Advanced Technology (DIAT), Ministry of Defence, Govt. of India, Pune-411025, India
S.
Kakatkar
Atmospheric Microwave System (AMS) Division, Society for Applied Microwave Electronics Engineering and Research (SAMEER), IIT Campus, Mumbai-400076, India
coaxial cable
coupler
miniaturization
quadrature hybrid
VHF
Wilkinson power divider
In this article, novel implementations of Wilkinson Power Divider (WPD) and Quadrature (90°) Hybrid Coupler (QHC) have been proposed using series and parallel combination of coaxial cables for Very High Frequency (VHF) applications. The proposed method of implementation using coaxial cables is advantageous in terms of its simplicity and it can work at higher power levels with proper choice of cables. Moreover, the fine tuning of the designed frequency for the proposed devices can be easily possible by merely trimming the cable length which is not easy with microstrip lines once its PCB fabrication is done. In addition, due to the use of flexible coaxial cables, there is good scope for miniaturization of the respective device. The proposed WPD and QHC show good matching at all the ports and very good amplitude balance, relative phase difference and isolation between the output ports. The proposed WPD and QHC show overall favorable performance fractional bandwidth respectively of 35.76% and 11.15%. In addition, the reduction in the lengths of the quarter wavelength transmission line sections of WPD is upto 55% and an overall size reduction of 23.50% has been achieved in QHC as compared to that of their respective conventional microstrip line designs, with potential for further miniaturization.
TWO-FREQUENCY APPROACH TO DETERMINE A TORCH DISCHARGE RESISTANCE WITHIN M.S. NEIMAN EQUIVALENT CIRCUIT WITH ADDED EQUIVALENT INDUCTANCE OF THE DISCHARGE
1375-1388
10.1615/TelecomRadEng.v77.i15.80
A. O.
Puzanov
A. Usikov Institute of Radio Physics and Electronics, National Academy of Sciences of Ukraine, 12, Academician Proskura St., Kharkov 61085, Ukraine
torch discharge
Neiman model
torch discharge inductance
torch discharge resistance
The practical value of the study presented is obvious due to the great potential of torch discharge (TD) for a variety of applications though being hindered by a substantial lag in its practice-oriented theoretical research. This paper considers a new approach suggested by the author to measure a TD resistance (Rd) with the discharge inductance L being taken into account. The approach is backed-up with formulae enabling one to calculate Rd from the data measured at two frequencies, which are values of function α, a voltage relation, at which the electrical and geometrical characteristics of the torch discharge remain unchanged. In particular, through this formula for Rd, an inequality was found allowing us to estimate the definition domain of α. It is established that the frequency dependence of α has its minimum at the resonance frequency of the discharge circuit ωr, which becomes an asymptote at L → 0 for a similar dependence of α at L ≡ 0. It is shown that in cases, when the effect of L cannot be neglected, the minimum of function a is always located above the asymptote at the ordinate axis. A conclusion was made that the measured value of α should correlate with the accuracy of the measuring equipment including devices that control the constancy of geometrical parameters of the torch discharge excited at two frequencies. Therefore, the measured value of a has to be as low as possible. It is feasible if the excitation frequencies are significantly spaced apart. The proposed approach provides a higher industrial resource efficiency.
RADIO TECHNOLOGY IN BIOMEDICAL INVESTIGATION
1389-1395
10.1615/TelecomRadEng.v77.i15.90
Ya. V.
Nosova
Kharkiv National University of Radio Electronics, 14 Nauka Ave, Kharkiv 61166, Ukraine
Kh. I.
Faruk
Kharkiv National University of Radio Electronics, 14 Nauka Ave, Kharkiv 61166, Ukraine
O. G.
Avrunin
Kharkiv National University of Radio Electronics, 14 Nauka Ave, Kharkiv 61166, Ukraine
olfactory test
odorivector
test-retest reliability
rhinomanometer
olfactometry
energy characteristics
There are many methods for assessing impaired olfaction, but odorivectors used for testing exclude feasibility of creating a standardized common approach, therefore, the results of olfactory function tests cannot be strictly formalized. Also, most of the existing techniques for diagnosing abnormalities in the olfactory analyzer function are based on patient-subjective data, which in turn is also a substantial limitation. Thus, the goal of the present work is to develop a method for studying the respiratory and olfactory dysfunctions that would allow, by placing the carrier of an odorous substance in the airway of a rhinomanometer, as well as by
determining the energy characteristics of respiration, to associate breathing parameters with olfactory function parameters. This would allow performing effective and evidential tests of both respiratory and olfactory impairments. Here, we describe a technique for conducting studies of respiratory and olfactory disorders including the reliability evaluation of measurements by the proposed method. The calculations showed that test-retest-reliability coefficient corresponds to a high degree of reliability of the conducted measurements. The prospect of work is the choice of concentrations of odorous substances for differential diagnosis of the olfactory analyzer sensitivity disorders.