Radiofizika i elektronika最新文献

{"title":"A magnetoactive metamaterial based on a structured ferrite","authors":"S. Polevoy, G. Kharchenko, S. Tarapov, O. Kravchuk, K. Kuršelis, B. Chichkov, N. Slipchenko","doi":"10.15407/REJ2021.01.028","DOIUrl":"https://doi.org/10.15407/REJ2021.01.028","url":null,"abstract":"Subject and Purpose. The use of spatially structured ferromagnets is promising for designing materials with unique predetermined electromagnetic properties welcome to the development of magnetically controlled microwave and optical devices. The paper addresses the electromagnetic properties of structured ferrite samples of a different shape (spatial geometry) and is devoted to their research by the method of electron spin resonance (ESR). Methods and methodology. The research into magnetic properties of structured ferrite samples was performed by the ESR method. The measurements of transmission coefficient spectra were carried out inside a rectangular waveguide with an external magnetic field applied. Results. We have experimentally shown that over a range of external magnetic field strengths, the frequency of the ferromagnetic resonance (FMR) of grooved ferrite samples (groove type spatial geometry) increases with the groove depth. The FMR frequency depends also on the groove orientation relative to the long side of the sample. We have shown that as the external static magnetic field approaches the saturation field of the ferrite, the FMR frequency dependence on the external static magnetic field demonstrates \"jump-like\" behavior. And as the magnetic field exceeds the ferrite saturation field, the FMR frequency dependence on the groove depth gets a monotonic character and rises with the further growth of the field strength. Conclusion. We have shown that the use of structured ferrites as microwave electronics components becomes reasonable at magnetic field strengths exceeding the saturation field of the ferrite. At these fields, such a ferrite offers a monotonically increasing dependence of the resonant frequency on the external magnetic field and on the depth of grooves on the ferrite surface. Structured ferrites are promising in the microwave range as components of controlled filters, polarizers, anisotropic ferrite resonators since they can provide predetermined effective permeability and anisotropy","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67138377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On kinetics of superconducting state destruction in a nonlinear coplanar waveguide based on a high-temperature superconductor film","authors":"O. Lavrinovich, N. Cherpak","doi":"10.15407/REJ2021.01.049","DOIUrl":"https://doi.org/10.15407/REJ2021.01.049","url":null,"abstract":"Subject and Purpose. The mechanism of destruction of the S-state of a nonlinear high-temperature superconductor as part of a coplanar waveguide has not been properly elucidated as the effect of avalanche-type transition to a highly dissipative state, which was experimentally detected by the authors, takes place. The present work is concerned with the development of an appropriate approach describing kinetics of destruction of the S-state of a nonlinear high-temperature superconductor in a coplanar waveguide with allowances made for an inhomogeneous distribution of the microwave current in the superconducting film strip. Methods and Methodology. Use of I.B. and O.G. Vendiks’ reasoning [2] is made on kinetics of the destruction of the superconducting state of a wide film when a direct current governed by the time-dependent Ginzburg-Landau equation is applied. Keeping unchanged their idea as to the S–N boundary forming in the film strip with the boundary movement to the middle of the strip, the S–N boundary motion equation is obtained for a coplanar waveguide, proceeding in doing this from the motion equation of magnetic flux vortices under certain restrictions specified. Results. The time of S-state destruction has been numerically estimated: 1) for a wide superconducting film of YBa2Cu3O7–d composition, the destruction is by the direct current and 2) for a coplanar waveguide based on the same film, the destruction is by the microwave current. When the superconductivity is small (I / I c ³ 1), the destruction time values in both cases are close to each other within the order of magnitude. Conclusion. It is for the first time that the S-state destruction time in a coplanar waveguide has been expressed in terms of the microwave current distribution in the waveguide. It has been shown that this characteristic linearly depends on the ratio between the critical current and the microwave current amplitude in contrast to a quadratic dependence obtained for a superconducting strip with a direct current.","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67138393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Peculiarities of wheat seed resonant exposure to microwave radiation through oxygen-enriched water","authors":"O. Kovalenko, F. Kivva, A. Roenko","doi":"10.15407/rej2021.03.038","DOIUrl":"https://doi.org/10.15407/rej2021.03.038","url":null,"abstract":"Subject and Purpose. Peculiarities are considered of a purposeful modification of the functional indices of wheat seeds upon their soaking in water preliminarily enriched with oxygen and simultaneously irradiated with a low-intensity electromagnetic field (EMF). The aim is to investigate effectiveness of such an indirect exposure of wheat seeds to a low-intensity electromagnetic field related to discrete bands in the extremely high-frequency (EHF) range and depending on the initial state of seeds, “norm” or “pathology”. Methods and methodology. The study comprises experimentally approved radio-physical, radio-engineering and chemical methods. Generators G4-141 (37.5…53.57 GHz) and G4-142 (53.57…78.33 GHz) serve as radiation sources. Oxygen is obtained by reacting a hydrogen peroxide solution with potassium permanganate. The oxygen enrichment of water is executed during its irradiation. The verification of indirect electromagnetic field exposure is based on changes demonstrated by such functional indices of seeds as germination energy and mean lengths of roots and seedlings in each sample. Results. A possibility has been established to modify the functional indices of wheat seeds through their soaking in water preliminarily irradiated with an EMF and simultaneously enriched with oxygen. It has been revealed that the efficiency of the effect depends on whether the seeds are in “normal” or “pathological” state and that a feasibility exists of recovering properties lost in a “pathology” state. The role that the oxygen in the water imbibing the seeds plays in the germination process has been demonstrated. Peculiarities as to the efficiency of wheat seed EMF exposure through the oxygen-enriched water have been shown depending on the signal frequency and length of exposure and on the total energy load. Conclusion. It has been found that substances, including living entities, can be electromagnetically exposed through water. The water-dissipative model of substance exposure to the electromagnetic field has been validated. In this model, water is one of the targets liable to changing its properties at the EMF exposure. This point has been indirectly confirmed by the studies of the states of seeds upon their soaking in the pre-irradiated water. The gas model of the EMF interaction with a substance has been verified, too. A possibility of oxygen activation at resonance irradiation has been shown.","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67138463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A low temperature study of electromagnetic energy loss in low-loss materials in the 110…140 MHz frequency range","authors":"V. Derkach, E. Alekseev, R. Golovashchenko, Y. Ostryzhnyi, A. Meshcheryakov, S. Tarapov","doi":"10.15407/rej2020.03.042","DOIUrl":"https://doi.org/10.15407/rej2020.03.042","url":null,"abstract":"","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43795853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of surface parameters for backscattering simulation in the millimeter and centimeter wave regions","authors":"A. Bukin, V. Gutnik, Y. Lohvinov, N. Reznichenko","doi":"10.15407/rej2020.03.034","DOIUrl":"https://doi.org/10.15407/rej2020.03.034","url":null,"abstract":"","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42972620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green's function of a pulse sound source in a uniform subsonic flow","authors":"A. Bryukhovetski, A. Vichkan'","doi":"10.15407/rej2020.03.026","DOIUrl":"https://doi.org/10.15407/rej2020.03.026","url":null,"abstract":"","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46274877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resonant properties of an impedance monopole located on a perfectly conducting rectangular screen","authors":"N. Yeliseyeva, S. Berdnik, V. Katrich","doi":"10.15407/rej2020.03.003","DOIUrl":"https://doi.org/10.15407/rej2020.03.003","url":null,"abstract":"","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45270267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electromagnetic wave diffraction on a “strip grating – ferromagnetic half-space” composite structure: surface-wave resonances","authors":"A. Brovenko, P. Melezhik, A. Poyedinchuk, A. S. Troschylo","doi":"10.15407/rej2020.01.011","DOIUrl":"https://doi.org/10.15407/rej2020.01.011","url":null,"abstract":"Subject and Purpose. A theoretic study is given to the diff raction of a monochromatic plane E -polarized electromagnetic wave on a composite structure like a periodic strip grating bordering a half-space fi lled with a lossy homogeneous gyrotropic ferromagnetic medium. The work seeks to develop a method of the diff raction problem solution and determine diff raction characteristics of the electromagnetic wave interaction with the composite structure in the frequency region where the eff ective permeability of the ferromagnetic medium takes negative values. Methods and Methodology. The method of the diff raction problem solution is based on the analytical regularization idea. The initial diff raction problem in terms of Maxwell’s equations is equivalently reduced to the Riemann problem in theory of analytical functions. The problem is explicitly solved to yield an infi nite system of linear algebraic equations for the Fourier coeffi cients of the diff raction fi eld expansion in plane (Floquet) modes, which is solved by truncation. Results. A solution method has been developed for the diff raction problem of plane waves on a periodic strip grating bordering a ferromagnetic half-space. A theoretic prediction has been made that the E -polarized plane wave refl ection coeffi cient of the ferromagnetic half-space bordered by a strip grating has resonances in the frequency region where the medium permeability takes negative values. It has been found that these resonances are mainly caused by the repeated refl ection of the surface wave of the ferromagnetic half-space from the grating strip edges. Conclusion. The developed solution method for the plane electromagnetic wave diff raction on a periodic strip grating lying on the medium interface can be generalized to the consideration of planar ferromagnetic layers instead of the ferromagnetic half-space. The theoretically predicted resonances of the refl ection coeffi cients can be essential to the synthesis of radar absorbing coatings.","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47270263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Space-borne radar observation of near-surface wind effect on anomalously highly-directional backscattering of radio waves from aeolian processes of sand and dust transporting in desert regions","authors":"Dmytry Bychkov, V. Ivanov, A. Matveyev, V. Tsymbal, S. Yatsevich","doi":"10.15407/rej2020.01.021","DOIUrl":"https://doi.org/10.15407/rej2020.01.021","url":null,"abstract":"Aeolian process of sand and dust transporting is known to form the near-ground surface structures over vast territories and fill the atmosphere up with suspended aerosols-like dust particles which are spread then by winds over long distances. The presence of atmospheric dust in the planet's environment is one of the factors affecting the temperature and climatic conditions of vast regions of the Earth. A number of publications (Ivanov et al., 2015; Ivanov et al., 2016; Ivanov et al., 2016; Ivanov et al., 2018) analyze the revealed effect of anomalously highly(narrow) directed backscattering of radio waves which manifests itself in radar remote sensing (in range of local irradiation angles θ ≈ 31°÷32°) in areas covered with deep sand. At the same time, there is no specific data available from published studies investigating the impact of the near-surface wind on anomalously highly-directional backscattering of radio waves based on the results of radar remote sensing researches of Aeolian sand and dust transport processes in desert regions that, in turn, could have been used later to determine the parameters of such transport process. This article presents the results of analysis of the data obtained from long-term studies of desert regions of El-Djuf, Akshar and Trarza in Mauritania by means of space-borne SAR Envisat-1. The purpose of the analysis was actually to identify the specifics of the effect that the near-surface wind has on the anomalously highly-directional backscattering of radio waves which is identified by radar based researches of Aeolian processes of sand and dust transport in desert regions, so can be used for remote determination of such transportation parameters.","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48106401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of frequency dispersion of a negative-permittivity layer on electromagnetic wave tunneling through a three-layer structure","authors":"N. Beletskii, S. Borysenko","doi":"10.15407/rej2020.02.003","DOIUrl":"https://doi.org/10.15407/rej2020.02.003","url":null,"abstract":"","PeriodicalId":52841,"journal":{"name":"Radiofizika i elektronika","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67138035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}