Physics of Wave Processes and Radio Systems最新文献

{"title":"Peculiarities of the spectrum of reflected and transmitted light of circular polarization for a thin layer of an anisotropic wurtzite-type crystal near phonon resonance","authors":"Valery V. Yatsyshen, Irina I. Borodina","doi":"10.18469/1810-3189.2023.26.4.10-16","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.4.10-16","url":null,"abstract":"Background. Polaritons attract the attention of researchers and engineers with their unique properties and promising applications in the field of micro- and nanoelectronics. Such applications could include devices such as transistors or even polaritons lasers, as have been reported in the scientific literature. Aim. The work analyzes the frequency reflection spectra upon excitation of polaritons, and also considers the change in the polarization ellipse upon reflection of circularly polarized light from an anisotropic crystal. Methods. Based on the wave equation in an anisotropic medium, a dispersion equation for polaritons is derived. To calculate energy reflection coefficients using the characteristic matrix method. Results. An aluminum nitride AlN crystal was chosen as the object of analysis. It is shown that the use of circularly polarized incident radiation makes it possible, using an anisotropic crystal, to change the nature of polarization from circular to almost linear polarization. Conclusion. The found dependence of the polarization of reflected light can be used in electronic devices based on polaritons.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"291 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139178540","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":"Active and passive sensors for diagnostics quasi-zenith ionospheric HF communication channels","authors":"Dmitry V. Ivanov, Vladimir A. Ivanov, N. Ryabova, A. Elsukov","doi":"10.18469/1810-3189.2023.26.4.60-67","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.4.60-67","url":null,"abstract":"Background. There is a growing need for active sensory diagnostics of partial HF channels to provide frequency support to quasi-zenith HF radio links in varying signal propagation conditions. Enhancing the efficiency of active sensor algorithms, particularly by reducing emission time, is topical. To address this, a transition from sequential to parallel (simultaneous) diagnostics is proposed. Another significant challenge in HF communication is narrowband interference, and overcoming this issue involves the method of passive sensory diagnostics. This method assesses the availability of partial channels by analyzing the spectral density of interference power within them. Aim. The goal of this study is to develop algorithms and software tools that implement spectral monitoring and parallel sensing of partial channels for sensory diagnostics of ionospheric channels in quasi-zenith HF communication. Methods. The proposed approach involves integrating dynamic diagnostic methods into the development of intelligent sensors for ionospheric HF radio links, along with the creation of data analysis methods. Specialized computer software is employed to address the defined tasks. Experimental studies are conducted using the developed devices, which include intelligent active and passive radio sensors for HF radio links, to assess the load on HF communication channels. Results. A sensor for orthogonal quasi-zenith ionospheric radio channels has been created, incorporating algorithms for synthesizing a group pulse with orthogonal subcarriers while minimizing the peak factor. Additionally, algorithms for separating subcarriers and calculating the correlation function at the reception have been developed. The sensor employs the OFDM-BPSK signal modulation method, enabling operation in simultaneous-sequential sounding mode across the potential frequency range for communication. This led to an 8-fold reduction in the total signal emission time. Conclusion. The scientific results obtained have broad practical applications, particularly in enhancing the efficiency of wideband HF communication systems using spread spectrum signals.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"695 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139178291","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":"The wireless communications systems in subterahertz frequency range","authors":"Vladimir V. Biryukov, V. L. Vaks, Sergey A. Kapustin, V. A. Malakhov, A. Panin, S. Pripolzin, A. S. Raevskiy, Yuliya V. Raevskaya, Vladimir V. Shcherbakov","doi":"10.18469/1810-3189.2023.26.4.48-59","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.4.48-59","url":null,"abstract":"Background. The subterahertz and terahertz frequency ranges are very promising for development of high speed wireless communications systems because of possibility to get the bandwidth about some tens of GHz, which provides the high channel capacity. However fast signal attenuation at its propagation in atmosphere complicate the operation of communications systems in these ranges. Aim. Use of fixed narrow-beam antennas with high antenna power gain allows to provide the direct surface communications distance to some kilometers. The communications distance limitation can be partially removed decreasing the frequency down to 200 GHz and narrowing the channel bandwidth down to some GHz. Methods. The model of transmitter-receiver system (200-220 GHz) based of modern semiconductor devices is described in the manuscript. Results. The possibility of digital signals transmission with speed up to 1 Gbit/s at the distance of 1 km is experimentally shown. Conclusion. According to calculations the output power of transmitter about some hundreds mW is enough for data transmission at the distance up to 1.5 km with antenna power gain of no less than 50 dB.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"2 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139178691","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":"Application of complex-valued convolutional neural networks for equalization and detection of SEFDM systems","authors":"Larisa I. Averina, Oleg K. Kamentsev","doi":"10.18469/1810-3189.2023.26.4.95-103","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.4.95-103","url":null,"abstract":"Background. The disadvantage of spectrally efficient signals with frequency multiplexing is the occurrence of intersymbol interference, which is further aggravated when these signals propagate in frequency selective channels. Aim. The possibility and effectiveness of using neural network approaches for channel equalization and signal detection in communication systems using SEFDM signals has been assessed. Methods. A receiver structure for SEFDM systems based on a deep complex-valued convolutional neural network is proposed, which allows recovering bits from the temporal representation of the signal without using the fractional Fourier transform and inverting the cross-correlation matrix between frequency subcarriers. A two-stage network training scheme has been developed. Based on simulation modeling, a comparative analysis of the noise immunity of SEFDM systems was carried out both in a channel with white Gaussian noise and in a channel with Rayleigh fading, using classical and neural network receivers. Results. It is shown that there is no loss of noise immunity in channels with additive white Gaussian noise and an increase in noise immunity of the system up to 2 dB in the channel specified by the extended automotive model (3GPP-EVA). Conclusion. The effectiveness of using deep neural complex-valued convolutional networks as receivers for spectrally efficient communication systems, as well as their advantage over classical ones, is shown.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"374 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139178015","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":"Frequency criterion for stability «as a whole» of modulation-type pulse voltage converters according to Lyapunov","authors":"V. F. Dmitrikov, Lev E. Frid, A. Y. Petrochenko, D. V. Shushpanov","doi":"10.18469/1810-3189.2023.26.4.17-37","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.4.17-37","url":null,"abstract":"Background. The use of methods for researching and designing stable nonlinear dynamic systems by constructing the frequency characteristics of the loop gain of the negative feedback of a pulsed voltage converter through time characteristics obtained by numerical methods for solving nonlinear differential equations that describe electromagnetic processes in the converter takes a lot of time and has low accuracy in calculating optimal modes, when you need to calculate hundreds of options. Aim. Therefore, it seems necessary to further develop the theory of stability of modulation-type pulse voltage converters using frequency stability criteria, Lyapunov functions, amplitude and phase frequency characteristics of the converter loop gain. Methods. Stability in the «small» is solved using linearized models, which are constructed using the so-called first Lyapunov method - the «first approximation» method. The second method for studying the stability of nonlinear dynamic systems is the harmonic linearization method, when the nonlinear element is replaced by a harmonically linearized link with a transmission coefficient only for the first harmonic. Results. The Lyapunov function for a pulse voltage converter with nonlinear relay-type elements was found. Conclusion. The results obtained in the work make it possible to simplify the design of Lyapunov-stable pulse voltage converters through the use of the method of amplitude-frequency characteristics used for stationary linear systems.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"92 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139178552","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":"Analysis of the thermal effect of two external parallel printed circuit board conductors set on a metal base and operating in a space vacuum on each other","authors":"Aleksey V. Kostin","doi":"10.18469/1810-3189.2023.26.4.38-47","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.4.38-47","url":null,"abstract":"Background. The need to analyze the thermal effect of two external parallel conductors is due to an increase in the density of the conductive pattern. For printed circuit boards set on a metal base and operating in the vacuum of space, this need is aggravated by the weakness of the issue’s development. Aim. Analysis of the mutual influence of two external parallel printed circuit board conductors set on a metal base and operating in a space vacuum on each other to identify the dependence of their temperature on the distance between them and determine the distance at which this dependence practically disappears. Methods. To achieve the purpose, a finite element method calculation implemented in the ANSYS program, the Steady-State Thermal module, was used. Three multilayer printed circuit boards were calculated: 4-layer, 6-layer, 8-layer. The temperature coefficient of resistance was taken into account separately, by recalculation. Results. Graphs of the dependence of overheating (the difference between the temperature of the printed conductor and the metal base) on the distance between the printed conductors were constructed. The approximation of the obtained results is carried out. According to the approximated dependencies, the minimum values of the distances between printed conductors are found, at which the cross influence of printed conductors practically disappears. As the thickness of the printed circuit board increases, this distance increases. Conclusion. The results obtained can help to assess the influence of neighboring printed conductors in the design of the boards of the onboard equipment of spacecraft.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"214 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139178906","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":"Thermal entanglement in two-atom Tavis–Cummings model with taking into account the dipole-dipole interaction","authors":"E. Bashkirov","doi":"10.18469/1810-3189.2023.26.2.9-17","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.2.9-17","url":null,"abstract":"Background. Interest in the study of entangled states of systems of natural and artificial atoms (qubits) interacting with selected modes of microwave resonators is associated with their use as logic elements of quantum computers. At the same time, the most important task of the physics of quantum computing is the choice of the most effective mechanisms for manipulating and controlling the entangled states of qubits in such devices. Aim. The dynamics of the entanglement of two dipole-coupled superconducting Josephson qubits induced by a thermal noise of a coplanar resonator is studied for various initial states of the qubits. Methods. Based on the exact solution of the quantum Liouville equation for the whole density matrix of the system under consideration, the time behavior of the qubit entanglement parameter (negativity) is found for chaotic thermal, pure separable, and entangled initial states of qubits. Results. It is shown that the entanglement of qubits induced by the thermal noise of the resonator is possible for both the chaotic thermal states and separable states of qubits, except the case when both qubits are excited. It has also been found that, for small values of the dipole–dipole interaction parameter, taking this interaction into account leads to an increase in the degree of entanglement. For values of the dipole-dipole interaction parameter greater than some limit value, the opposite effect takes place. It is found that for entangled initial states of qubits, the inclusion of direct interaction has a small effect on the entanglement dynamics. It is shown that the initial coherence of qubit states can lead to a significant increase in the degree of their entanglement in the presence of a dipole–dipole interaction. Conclusion. The dipole-dipole interaction can be used as an effective mechanism for qubits entanglement manipulation and controlling.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":" 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132074648","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":"Practical realization of space-time filtering of satellite navigation signals in real time","authors":"Y. I. Glushankov, V. I. Tsarik","doi":"10.18469/1810-3189.2023.26.2.64-69","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.2.64-69","url":null,"abstract":"Background. The problem of satellite navigation signals’ jamming-protected receivers design is quite relevant due to the high vulnerability of such signals to the influence of interferences whose sources number is constantly increasing. Aim. To design a space-time adaptive filter and to implement its work in real-time as a part of jamming-protected satellite navigation system. Methods. The space-time filtering method fitted for the real-time realization is obtained based on the satellite signal space processing algorithm. The apparatus chosen for the satellite navigation signals reception, the filtering algorithm practical realization and the processed signal demodulation is described. The computer modeling of the signals records filtering and demodulation using the obtained algorithm as well as the real-time experiments in satellite signals processing with different numbers of outer jammers using the constructed jamming-protected receiver are carried out. Results. As a result of modeling and experiments with the designed set the values of performance characteristics of the jamming-protected navigation system are yielded which correspond to a good quality solution of the interference mitigation problem in a satellite navigation signal. Conclusion. The digital processing model based on the obtained space-time filter adequately describes the interference mitigation process in a real satellite signal. The obtained jamming-protected satellite navigation signal receiver is functional and can be used in practice.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121449894","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":"The structure of the radiation field of a symmetric slot line perpendicular to the edge of an infinite half-plane, taking into account the cross-polarization component","authors":"Eugeniy I. Nefyodov, I. N. Ponomarev, Viacheslav P. Zayarnyi","doi":"10.18469/1810-3189.2023.26.2.27-35","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.2.27-35","url":null,"abstract":"Background. Symmetric slot lines on a perfectly reflecting half-plane are good mathematical models for slot antennas on an ideal plane of finite dimensions, which in practice have a high gain and operate over a wide frequency band. These antennas are used in ultra-fast information processing systems based on microwave and optical volume integrated circuits. Aim. The work presents a solution to the problem of radiation of a perfectly reflecting half-plane, which was excited by a symmetric slot line with a different law of slot expansion. Methods. The problem was solved by the Fourier variable separation method, by which the Green tensor function was obtained, which connects the two components of the antenna radiation field with the excitation field in the gap. Results. It is shown that in the far zone, the radiation field of an ideally reflecting half-plane has two components: the main and crosspolarization. The Green tensor function has a complex form and consists of two terms. The analysis of the Green tensor function shows the participation of each term in the formation of a field in the far zone, demonstrates the mechanism of radiation and leads to known special cases for slot radiators. Conclusion. The validity of the presented mathematical model is confirmed by experimental research.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134421663","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":"The accuracy of measuring the coefficients of transmission and reflection of materials in the presence of random errors in the formation of fields","authors":"E. S. Emelyanov, O. E. Kiryanov, V. A. Ponkin","doi":"10.18469/1810-3189.2023.26.2.58-63","DOIUrl":"https://doi.org/10.18469/1810-3189.2023.26.2.58-63","url":null,"abstract":"Background. One of the characteristic features of the current stage in the development of military equipment is the widespread use of special structural materials and coatings with specified properties of interaction with electromagnetic fields, which are subject to measurement during production and operation. Most often, measurements are carried out in quasi-flat radiation and reception fields. At the same time, the regularities of the influence of random errors in the formation of flat fields on the accuracy of measuring the characteristics of special structural materials and coatings have not been studied enough. Aim. The purpose of this work is to establish quantitative patterns of the influence of random phase errors in the formation of flat fields on the errors in measuring the transmission and reflection coefficients of materials and coatings. Methods. Studies of the influence of random phase errors in the formation of flat fields of irradiation and signal reception on the accuracy of measuring the transmission and reflection coefficients of objects were carried out using the methods of mathematical modeling and statistical radio engineering. Results. Calculation relations are obtained for estimating the magnitude of errors in measuring the transmission and reflection coefficients. Conclusion. With small errors and a small interval of spatial correlation, the errors of the measured average values of the transmission and reflection coefficients are proportional to the errors in the formation of the irradiation and reception fields and the relative value of the spatial correlation interval must exceed 22 degrees.","PeriodicalId":129469,"journal":{"name":"Physics of Wave Processes and Radio Systems","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114917345","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}