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Radars which able to diagnose the state of living organisms, can find the widest application. The estimation method of respiration and heartbeat parameters of the man was offered. The mathematical modeling for algorithm optimization of obtaining the necessary signals and determination of their spectral characteristics are carried out.
The present paper concerns the development and approbation of the method of resonant near-field microwave to-mography with regard to problems on early diagnostics of melanoma and other skin neoplasms.
The qualitative comparative analysis of myocardium heat field was carried out using thermograph in the spectral range of 8 ??? 14 microns. There was made the quantitative assessment of head and myocardium temperature measurement accuracy which depends upon the ambient temperature. Based on the proposed approach to the analysis of head and myocardium thermograms, we carried out the study of thermo-abnormal...
The report describes, for the first time, the creation of complex switched-capacitor microwave filters, the features of complex FIR and IIR filters constructing on the basis of switch-capacitor (SC) circuits. Separately, a choice of phasing for building the SC-device is discussed in accordance with its functional scheme. Authors offer the new SC circuit of complex delay. The report also contains the...
An installation for visualization of objects using conductive magnetic induction measurements by the matrix of flat spiral coils is designed. The coils are installed in a matrix of 4 rows, each row shift allows increasing density measurements in case of a linear scan. The results of experimental studies of visualization of different metal objects are presented.
Some ways for measurement accuracy improvement of UWSNP microwave device are considered. Main of them take into account errors under registration of frequency-dependent relative reflected power, choice of operation part of frequency range, careful plant calibration of each sample of the device. Using the device modification UWSNP-2M as an example under its on-site exploitation, an approach for optimal...
Mechanisms leading to the microwave generation breakdown and to the corresponding microwave impulse shortening in the relativistic virtode have been investigated with the help of CST Particle Studio. It has been discovered that this breakdown is conditioned by the qualitative change of beam dynamics during the process of the suppression of generation in the system. Obtained results is principally...
The paper considers the diocotron instability arising in relativistic beams in crossed fields. Using analytical and numerical models, a degree of instability growth is analyzed at different beam parameters and external crossed fields' intensity. The shape of the extended electron beam is analyzed after the excitation of the instability in it.
Improper gliding and leakage waves in dissipative structures are considered. Such gliding surface wave is the Zenneck wave over the dissipative plane, the existence of which in a number of publications is in doubt until the present days. Here we show the falsity of such publications and give a historical overview on the mentioned problem. The calculated parameters of the Zenneck wave over the sea,...
The present paper presents the methods of correction of the phase angle error of the phase splitters (PS) of microwave band based on the classical differential stage. The synthesis strategy of design correction circuits of the second order, providing reduction of the parasite phase shift up to ???????2 degree between the output signals of phase splitter in the frequency band up to 8 ??? 13 GHz in...
Studies have shown that in the local approximation, the behavior of electrical properties of semiconductor surfaces, interfaces, processes of current flow and charge transport, as well as the majority of technological processes on the nano-level satisfy all properties of chaotic systems. In the local approximation, the dependences of the electrophysical properties of objects and geometry of technological...
The feature of the phase shifter under study is a set of identical connected cascades in T-scheme. The results of numerical modeling are presented. The studied device is optimized for S-parameters in the frequency range; phase and amplitude characteristics of return loss and insertion loss are investigated. Thus, the possibility of modeling of a microwave module of an analog phase shifter based on...
The possibility to create waveguide structures based on diaphragm with coupling elements placed astride it, which have both allowed and forbidden bands, had been shown experimentally. It was shown that introducing the heterogeneity kind of ???dowel with gap??? into the construction provides the appearance of the resonance singularity kind of low-loss transmission window in the forbidden frequency...
The method of infection diseases diagnosing is considered within the bounds of information-extreme intelligence technology, which is based on maximization of informational capability of a decision support system in the study process by means of sequential optimization of the redundant binary training matrix. Implementation of the proposed algorithm was done for GRID-center of acute enteric infection...
Two techniques for calculating the large signal S-parameters (LSSPs) of nonlinear microwave circuits, i.e., the frequency splitting method and circuit modification method, are compared. It is shown that in contrast to the small signal case, LSSPs calculated by different techniques will be inevitably distinct due to distortion of an initial stationary operating mode of the circuit. However, these differences...
The paper presents the results of a natural experiment on the use of GPR for probing and imaging of aquifers. GPR ???OKO-2??? was used for the studying of soil. The basic processing steps and the results are shown. The proposed technique in the processing of radar tracks showed that the presence of underground aquifers can help to restore the real terrain relief without using special vertical positioning.
The three-dimensional instrument functions of synthetic aperture LFM-radar using MIMO-lines with different topologies are studied by means of numerical simulation. A comparison with usual synthetic aperture radar was carried out.
The modification of the algorithm for radio holographic synthesis of 3D-images based on probing LFM-signal is developed. The modification takes into account the effect of refraction at the boundary with a receiving environment. Double improvement in resolution and geometric similarity image subsurface objects are shown experimentally.
The present paper proposes a method for the detection and recognition of subsurface objects, in which the processing of the received signals used information about the electrophysical parameters of the soil in the frequency range used by the probing of UWB (ultra-wideband) signal.
It was shown for the first time that the exposure of laboratory SHK mice to low-intensity modulated extremely high-frequency electromagnetic radiation (EHF EMR) with effective parameters (carrier frequency of 42.2 GHz, intensity of 0.1 mW/cm2, exposure duration for 20 min, pulse modulation with a frequency of 1 Hz) before and after treatment with X-rays at a dose of 4 Gy caused pronounced radiation...
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