Signal Formation Research Articles

Local Mean Decomposition and Weighted Kurtosis Index for Bearing Defect Detection

Vibration signal analysis is an effective technique for detecting bearing defects, and it proposes an approach that involves signal processing methods to extract information about the defects. The initial step in the proposed approach involves dividing the signal into several components (PF) using the LMD algorithm. Subsequently, the weighted kurtosis index (WKI) values are computed, and the summation of components having WKI values higher than the average of WKI leads to the formation of a new signal containing multiple pulses that are very similar to the original signal. Then we can observe peaks at the frequencies of the bearing defects in the envelope spectrum of the new signal. Applying the proposed approach to the vibration signal available in the XJTU database shows a peak at the fault frequency of the outer ring.

Effect of laser parameters and shielding gas flow on co-axial photodiode-based melt pool monitoring signals in laser powder bed fusion

Melt pool monitoring using co-axial photodiodes is increasingly used for online quality monitoring in PBF-LB AM. However, the fundamental correlations between different processing conditions and the co-axial photodiode signals are not well understood. In this study the impact of laser parameters and the shielding gas flow speed on co-axial photodiode-based melt pool monitoring signals is established. It is shown that laser power has positive linear correlation with the photodiode signal, while the correlation with scanning speed is non-linear in the form of y=ax–b. The focal point position, scanning orientation and shielding gas flow speed have highly non-linear response on the photodiode signal, depending on the combinatorial effects of the parameters. These underlying physical correlations should be carefully assessed and taken into consideration when trying to establish correlations between photodiode-based melt pool monitoring signal and defect formation in the PBF-LB process.

MEK inhibitors lead to PDGFR pathway upregulation and sensitize tumors to RAF dimer inhibitors in NF1-deficient malignant peripheral nerve sheath tumor (MPNST).

Malignant peripheral nerve sheath tumor (MPNST) is a highly aggressive subtype of soft tissue sarcoma with a high propensity to metastasize and extremely limited treatment options. Loss of the RAS-GAP NF1 leads to sustained RAF/MEK/ERK signaling in MPNST. However, single-agent MEK inhibitors (MEKi) have failed to elicit a sustained inhibition of the MAPK signaling pathway in MPNST. We employed pharmacological, biochemical, and genetic perturbations of the receptor tyrosine kinase (RTK) and MAPK signaling pathway regulators to investigate the mechanisms of MEKi resistance and evaluated combination therapeutic strategies in various preclinical MPNST models in vitro and in vivo. Here, we report that MEKi treatment resistance in MPNST involves two adaptive pathways: direct transcriptional upregulation of the receptor tyrosine kinase (RTK) PDGFRβ, and MEKi-induced increase in RAF dimer formation and activation of downstream signaling. While the pharmacological combination of MEKi with a PDGFRβ specific inhibitor was more effective than treatment with MEKi alone, the combination of MEKi and RAF-dimer inhibitors led to a robust inhibition of the MAPK pathway signaling. This combination treatment was effective in vitro and in vivo, as demonstrated by the significant increase in drug synergism and its high effectiveness in decreasing MPNST viability. Our findings suggest that the combination of MEKi and PDGFR and/or RAF dimer inhibitors can overcome MEKi resistance and may serve as a novel targeted therapeutic strategy for NF1-deficient MPNST patients, which in turn could impact future clinical investigations for this patient population.

New insights into the singlet oxygen-independent formation of TEMPO signals in electron paramagnetic resonance analysis

Electron paramagnetic resonance (EPR) is currently the most commonly used technique for measurement of singlet oxygen (1O2) in advanced oxidation processes. However, the characteristic EPR signal associated with 1O2 (2,2,6,6-tetramethylpiperidine-N-oxide radical, TEMPO) can be generated via alternative pathways not involving 1O2, leading to misinterpreted results. In this study, in-situ EPR analysis was used to re-examine the interaction between peroxymonosulfate (PMS), a common oxidant, and 2,2,6,6-tetramethyl-4-piperidinol (TEMP), the spin-trapping agent of 1O2. It was found that TEMPO could be generated in TEMP/PMS system over a broad pH range (3.0–11.0). The pathway for TEMPO formation was the direct oxidation of TEMP by PMS, and 1O2 was not involved. Furthermore, the intensity of TEMPO (ITEMPO) followed a reverse parabolic pattern as the [TEMP]/[PMS] ratios changed across all pH values. Kinetic analysis unveiled three distinct patterns (continuous linear increase; linear increase followed by a lower rate of increase; increase followed by reaching a plateau) in ITEMPO. Finally, an electron transfer mechanism was proposed for the conversion of TEMP to TEMPO by PMS. The results from this study are expected to advance the understanding of 1O2-independent formation of TEMPO in TEMP/PMS and to mitigate the interference during the detection of 1O2 by EPR.

Effects of visual neuroplasticity training on visual perception, visual quality, and macular blood flow in patients with strabismus.

To observe the effects of visual neuroplasticity training on visual perception, visual quality, and macular blood flow in patients with concomitant strabismus postoperatively. In total, 108 patients underwent binocular strabismus correction operation, and some patients underwent neuroplasticity training. All patients underwent clinical ophthalmic examination, including measurement of best-corrected visual acuity, spherical equivalent, axis length, optical coherence tomography angiography, optical quality analysis system, and visual perception examinations. A total of 78 patients received neuroplasticity training for 1 month postoperatively, and 30 patients did not receive training. All patients underwent a visual perception examination preoperatively and at 1 day, 1 week, and 1 month postoperatively. Macular blood flow and visual quality were examined preoperatively and at 1 month postoperatively. Postoperative visual perception was better than preoperative visual perception (P < 0.05). After neuroplasticity training, the visual perception of the trained subjects was better than that of the untrained subjects (P < 0.05), and the blood flow in the macular area of the trained patients was lower than that of the untrained subjects (P < 0.05). The visual quality of the untrained subjects was lower than that of the trained patients (P < 0.05). Visual inspection system could accurately evaluate binocular visual perception in patients with concomitant strabismus. After surgical alignment of the strabismus patient, training can stimulate and integrate the formation of stereovision in a short period of time, maintain the visual quality of patients after surgery, and provide conditions for the formation of binocular visual signals and binocular stereovision, but in the short term, it will lead to the decrease of macular blood vessel density and perfusion density. However, the long-term effects of training have not been proven.

Formation of CBOC signals with a reduced level of out-of-band radiation

Formulation of the problem. The article considers the issues of choosing low-pass filters with finite and infinite pulse characteristics used to generate CBOC signals with phase manipulation with a reduced level of out-of-band radiation. Purpose. The influence of the filter frequency band on the distortion of CBOC signals in the frequency and time domain is estimated by mathematical modeling. Results. The following filter parameters, peak factor and ACPR (Adjacent Channel Power Ratio) were studied and calculated. Practical significance. The results obtained can be used by developers of local navigation systems.

On the Origin of the Photoplethysmography Signal: Modeling of Volumetric and Aggregation Effects

This study aimed to examine the mechanisms of the photoplethysmography (PPG) signal formation using Monte Carlo simulations of light transport in biological tissues and experimental observations. Based on a three-layer skin model in backscattering geometry, we sequentially simulated volumetric blood changes and the aggregation/disaggregation of erythrocytes in the dermal layer and estimated their contribution to the registered PPG signal. The calculations were conducted for two wavelengths: 525 nm and 810 nm. For green light, absorption predominates over scattering in the formation of a PPG signal, whereas, for near-infrared light, scattering prevails over absorption. This theoretical result was verified using the Modified Beer–Lambert law and clinical in vivo PPG data of seven healthy subjects. Changes in the size of the scatterers during erythrocyte aggregation and disaggregation can significantly contribute to the PPG signal at near-infrared light. Thus, for the green waveband, the classical volumetric model can be considered dominant in the PPG signal formation. In contrast, for the near-infrared range, both volumetric and aggregation effects must be considered as being approximately equal.

Обобщенная математическая модель радиосигнала в различных базисах

The purpose of this article is to develop a generalized mathematical model of a radio signal in various bases. The proposed model allows us to generalize the known models of radio signals in basis functions of sine/cosine, basis functions of spline characters, bases of spline-Vilenkin-Chrestenson functions, bases of spline-Pontryagin-Vilenkin-Chrestenson functions, etc., constructed on the basis of spline-algebraic harmonic methods analysis. For the generalized model, special cases are formulated for the considered spaces of basis functions. Block diagrams and timing diagrams are presented that explain the main stages of the formation and processing of radio signals in various bases. Using the simulation method in the Matlab environment, the noise immunity of the proposed radio signals was assessed. Analysis of the obtained results showed that radio signals generated on the basis of a generalized mathematical model in various noise immunity bases under AWGN conditions are comparable (and even have a slight advantage) with similar signals generated in the bases of classical exponential functions. An assessment of structural secrecy is presented. It is shown that the structural secrecy of radio signals generated in various bases is ensured by the formation of signals in a priori unknown bases, the parameters of which: group, ring, spline order and number of the basis function change in accordance with a given code word, also unknown to potential unauthorized processing systems. Structural secrecy manifests itself in the incorrect choice of basis when processing signal data for reception, which entails an expansion of the signal spectrum. As a result, incorrect estimation of signal parameters and incorrect setting of the demodulator occurs.

THE MEASUREMENT QUALITY EVALUATION OF AN ULTRASONIC FLOW SENSOR WITH A COMPLEX MEASURING PATH TRAJECTORY

Over the past ten years, ultrasonic measuring instruments have become most widespread in industrial measurements of the flow and quantity of various energy resources. Such instruments differ in design, method of obtaining the output signal, number and topology of acoustic waves propagation and, accordingly, have different metrological performances. The accuracy of the measured signal formation is determined by the quality of the flow sensor. At the same time, the components of quality are metrological performances, manufacturability of the design, ease of setup, cost and others. The purpose of the work is to compare, analyze and evaluate the quality of flow measurements when using a single-channel ultrasonic sensor with a complex trajectory of the measuring beam and a multi-path (multichord) ultrasonic sensor. As a result of simulation modeling, distributions of flow velocities in longitudinal sections and cross sections were obtained, correction factors for the measured signal were determined, and pressure losses were calculated. A comparative analysis of the measurement quality of the investigated flow sensors made it possible to identify the advantages of using a single-path flow transducer with acoustic wave reflection. We are talking about the possibility of accurately outputting a useful signal, higher metrological sensitivity, higher measurement accuracy, as well as minimal impact on the measured medium due to the creation of smaller geometrically sized local hydrodynamic resistance along the length of the measuring path. The further research prospect is the study of ultrasonic flow measuring sensors with different topologies of acoustic channels when measuring and recording flow and quantity for different flow regimes of the measured medium.

Development of parabolic antenna irradiator for tropospheric communication station

The currently existing tropospheric stations, due to high energy consumption and limited signal formation capabilities, and radio relay stations, also due to limited communication range, require new technological solutions. One such solution proposed is the creation of a tropospheric-radio relay station with completely redesigned radio equipment. The Institute of Special Communications and Information Protection, in collaboration with a research institute, developed a scheme for such a station, which was tested in field trials on a real tropospheric radio line with a length of 155 km. Our specialists were involved in the development of two antenna devices. A detailed analysis of the current state of tropospheric communication station development in the world was conducted, and the possibilities of modernizing existing stations, such as the R-423-M, were considered. Based on the results of the analysis, it was proposed not to conduct modernization, but rather to develop a new generation of tropospheric communication stations. According to the accepted station construction concept, its transmitting and receiving parts were developed as two separate units (external and internal). The external unit for conducting field trials was located on the antenna, allowing for the maximum reduction of signal losses in the antenna-feeder paths. The components of the internal units were housed in the closed body of a vehicle. This provided additional convenience for the operator and reduced the requirements for climatic conditions. The antenna block of the transmitter includes a power divider, a power amplifier block (eight power amplifiers of 10 W each), a two-mirror parabolic antenna with a hyperboloid small mirror, and an eight-element horn feed that can be powered in such a way that the output wave will be either linear or circular polarization.

The contribution of the vascular architecture and cerebrovascular reactivity to the BOLD signal formation across cortical depth.

Assessment of neuronal activity using blood oxygenation level-dependent (BOLD) is confounded by how the cerebrovascular architecture modulates hemodynamic responses. To understand brain function at the laminar level, it is crucial to distinguish neuronal signal contributions from those determined by the cortical vascular organization. Therefore, our aim was to investigate the purely vascular contribution in the BOLD signal by using vasoactive stimuli and compare that with neuronal-induced BOLD responses from a visual task. To do so, we estimated the hemodynamic response function (HRF) across cortical depth following brief visual stimulations under different conditions using ultrahigh-field (7 Tesla) functional (f)MRI. We acquired gradient-echo (GE)-echo-planar-imaging (EPI) BOLD, containing contributions from all vessel sizes, and spin-echo (SE)-EPI BOLD for which signal changes predominately originate from microvessels, to distinguish signal weighting from different vascular compartments. Non-neuronal hemodynamic changes were induced by hypercapnia and hyperoxia to estimate cerebrovascular reactivity and venous cerebral blood volume ( ). Results show that increases in GE HRF amplitude from deeper to superficial layers coincided with increased macrovascular . -normalized GE-HRF amplitudes yielded similar cortical depth profiles as SE, thereby possibly improving specificity to neuronal activation. For GE BOLD, faster onset time and shorter time-to-peak were observed toward the deeper layers. Hypercapnia reduced the amplitude of visual stimulus-induced signal responses as denoted by lower GE-HRF amplitudes and longer time-to-peak. In contrast, the SE-HRF amplitude was unaffected by hypercapnia, suggesting that these responses reflect predominantly neurovascular processes that are less contaminated by macrovascular signal contributions.

A model of the improved NOMA algorithm based on representation and modulation.

For the successful implementation of mobile communication networks in the spectral range of 30-300 GHz, it is necessary to solve several problems related to terminal subscriber devices. And one of the main problems is to be blocked by small line-of-sight transmission objects. Ways to solve this problem are densification of cellular infrastructure in the terahertz range with the help of mobile mobile communication nodes, as well as the use of simultaneous connection of subscriber terminals to two or more cells at the same time [1; 2]. In this work, an improved NOMA algorithm based on relaying and modulation called M-СО-NOMA is proposed to solve this problem. Unlike the known ones, it differs in that, firstly, before broadcasting into the radio air in the first time slot, terminal devices are clustered in the service area of the base station of the mobile network using the algorithm for estimating the fractal dimension and, secondly, during the formation of the general transport signal for terminal devices of subscribers, the base station modulates the signals of remote users on the quadrature, and the signals of nearby users on the real component of the QPSK constellation. The proposed improved M-CO-NOMA algorithm eliminates the main drawbacks of NOMA by introducing orthogonality at the stage of signal preparation instead of including it in the spectrum. It is shown that the proposed improved algorithm is effective in terms of such indicators as the reduction of SER, computational complexity, and interference compared to the usual NOMA. In addition, the integrated solution based on M-NOMA and СО-NOMA made it possible to obtain new innovative opportunities for ensuring data transmission when blocking direct transmission in the terahertz frequency range due to auxiliary signal relaying between subscribers. Calculation of the information efficiency of the developed integrated solution showed that for systems with NOMA and M-СО-NOMA, this indicator is equal to 4.50 e-2 and 6.00 e-2, respectively. Thus, the calculated information efficiency value of the M-CO-NOMA system is 1.5 times greater than that of NOMA.

A fully synthetic three-dimensional human cerebrovascular model based on histological characteristics to investigate the hemodynamic fingerprint of the layer BOLD fMRI signal formation.

Recent advances in functional magnetic resonance imaging (fMRI) at ultra-high field (≥7 tesla), novel hardware, and data analysis methods have enabled detailed research on neurovascular function, such as cortical layer-specific activity, in both human and nonhuman species. A widely used fMRI technique relies on the blood oxygen level-dependent (BOLD) signal. BOLD fMRI offers insights into brain function by measuring local changes in cerebral blood volume, cerebral blood flow, and oxygen metabolism induced by increased neuronal activity. Despite its potential, interpreting BOLD fMRI data is challenging as it is only an indirect measurement of neuronal activity. Computational modeling can help interpret BOLD data by simulating the BOLD signal formation. Current developments have focused on realistic 3D vascular models based on rodent data to understand the spatial and temporal BOLD characteristics. While such rodent-based vascular models highlight the impact of the angioarchitecture on the BOLD signal amplitude, anatomical differences between the rodent and human vasculature necessitate the development of human-specific models. Therefore, a computational framework integrating human cortical vasculature, hemodynamic changes, and biophysical properties is essential. Here, we present a novel computational approach: a three-dimensional VAscular MOdel based on Statistics (3D VAMOS), enabling the investigation of the hemodynamic fingerprint of the BOLD signal within a model encompassing a fully synthetic human 3D cortical vasculature and hemodynamics. Our algorithm generates microvascular and macrovascular architectures based on morphological and topological features from the literature on human cortical vasculature. By simulating specific oxygen saturation states and biophysical interactions, our framework characterizes the intravascular and extravascular signal contributions across cortical depth and voxel-wise levels for gradient-echo and spin-echo readouts. Thereby, the 3D VAMOS computational framework demonstrates that using human characteristics significantly affects the BOLD fingerprint, making it an essential step in understanding the fundamental underpinnings of layer-specific fMRI experiments.

Understanding photoacoustic signal formation in the presence of transparent thin films

Strain-induced variation of the refractive index is the main mechanism of strain detection in photoacoustic experiments. However, weak strain-optic coupling in many materials limits the application of photoacoustics as an imaging tool. A straightforward deposition of a transparent thin film as a top layer has previously been shown to provide signal enhancement due to elastic boundary effects. In this paper, we study photoacoustic signal formation in metal covered by thin transparent films of different thicknesses and demonstrate that in addition to boundary effects, the photoacoustic response is affected by optical effects caused by the presence of the top layer. The interplay of optical effects leads to a complex temporal signal shape that strongly depends on the thickness of the thin film.

ОДНОВИМІРНА ЗГОРТКОВА МОДЕЛЬ НЕЙРОННОЇ МЕРЕЖІ ДЛЯ ОБРОБЛЕННЯ СИГНАЛІВ З АМПЛІТУДНОЮ МОДУЛЯЦІЄЮ БАГАТЬОХ СКЛАДОВИХ

The processing of radio signals using artificial neural networks (ANNs) has great potential for research, which can be explained by the adaptability of ANNs to various transmission conditions and the ability to detect abstract patterns of changes in signal parameters. The article reviews the works of other authors devoted to different ways of using ANNs for processing radio signals. Taking into account the information in the reviewed works, the research task was formed, which consists in developing an optimized ANN model for radio signal processing. Signals with amplitude modulation of many components (AMMC) were chosen to form training samples for ANN. The choice of modulation type is justified by greater energy efficiency compared to other widely used digital modulation types, such as quadrature amplitude modulation. Mathematic basis of AMMC signal generation is described. The process of finding the coordinates of three component 8-AMMC signal constellation is explained, the formation of signals in the time plane based on the found coordinates is explained as well as their discretization and the addition of white noise. An iterative algorithm for generating initial data for ANN based on the described ratios is proposed. The general structure of one-dimensional convolutional neural network is considered. Functions of individual neurons, connections between them, the formation of layers and the convolution operation are described mathematically. On the basis of the previously given ratios, a final display of the network was formed. Specific dimensions and activation functions for layers are selected. The use of convolutional layers is justified by time invariance. Based on the reviewed mathematical models, selected activation functions and dimensions, a neural model was formed. The process of validating the effectiveness of the formed neural model is described, which is based on comparing the symbolic error probabilities of the proposed and reference models at different signal-to-noise ratios. The validation results are presented. The advantages of the obtained model over the previously proposed purely recurrent model and the AMMC reference receiver are explained.

Position-resolved charge collection of silicon carbide detectors with an epitaxially-grown graphene layer

Silicon carbide (SiC) has outstanding physical properties therefore, diodes based on SiC are being considered for many radiation detection applications such as particle accelerator experiments and medical dosimetry. Moreover, by reducing the metal on the surface of the diode there is the potential to enhance its performance in some fields where the presence of metal is detrimental. To this end, SiC detectors with an epitaxially-grown graphene layer (EG), that substitutes the metallic contact, in the sensitive region were produced at IMB-CNM, profiting from the conductivity of the mono-atomic layer material. To isolate the effect of the graphene on the charge collection, samples without graphene were produced in parallel. In this paper, the effect of EG on Silicon Carbide p-in-n radiation detectors is studied in terms of charge collection with a radioactive source and by means of the transient current technique (TCT), which allows for position-dependent signal formation analysis. As a result of the former, we show the capability of the EG-SiC sensor for charge collection after signal integration, to a resolution close to that of a sensor fully metallised. Moreover, from the TCT studies, we observe uniform charge collection across the active region, as well as an up-to ∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim $$\\end{document}40% transient amplitude damping which, compared with the ∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim $$\\end{document}90% on the sample containing no metallic contact, proves that the presence of graphene benefits the performance of the device and that the technology is viable for radiation detection as an alternative to metal.

Physics of the Signal Formation in Photopletysmography: Assessment of the Contribution of Light Absorption and Scattering to the Registered Flux of Optical Radiation

The paper is devoted to the study of physical mechanisms of photoplethysmography (PPG) signal formation using Monte Carlo simulations of light transport in biological tissue. The problem of estimating the contribution of absorption and scattering variations to the registered PPG signal is solved. Based on a three-layer skin model, changes in the optical properties of the dermal layer (absorption and scattering) were sequentially simulated and their contributions to the total signal were estimated. Calculations were carried out for two wavelengths, 525 nm and 810 nm. It was found that for green light the main contribution to the signal formation is made by absorption (88 % versus 12 % scattering, respectively). While for the near infrared light, scattering predominates over absorption. In this case, the contributions of absorption and scattering are 28 % and 72 %. Thus, for the green wavelength range the classical volumetric model of signal formation is valid. Whereas for the near-infrared range, the predominant factor in signal formation is scattering of the medium, which can change due to processes such as changes in orientation, aggregation and deformation of red blood cells, their concentration in the diagnostic volume of tissue, etc.

Evaluating Vascular Depth-Dependent Changes in Multi-Wavelength PPG Signals Due to Contact Force.

Photoplethysmography (PPG) is a non-invasive method used for cardiovascular monitoring, with multi-wavelength PPG (MW-PPG) enhancing its efficacy by using multiple wavelengths for improved assessment. This study explores how contact force (CF) variations impact MW-PPG signals. Data from 11 healthy subjects are analyzed to investigate the still understudied specific effects of CF on PPG signals. The obtained dataset includes simultaneous recording of five PPG wavelengths (470, 525, 590, 631, and 940 nm), CF, skin temperature, and the tonometric measurement derived from CF. The evolution of raw signals and the PPG DC and AC components are analyzed in relation to the increasing and decreasing faces of the CF. Findings reveal individual variability in signal responses related to skin and vasculature properties and demonstrate hysteresis and wavelength-dependent responses to CF changes. Notably, all wavelengths except 631 nm showed that the DC component of PPG signals correlates with CF trends, suggesting the potential use of this component as an indirect CF indicator. However, further validation is needed for practical application. The study underscores the importance of biomechanical properties at the measurement site and inter-individual variability and proposes the arterial pressure wave as a key factor in PPG signal formation.

Kinetics of Laser-Induced Thermal Emission of Porous Carbon Materials: Dependence on Laser Wavelength

For the porous carbon material excited by the first and second harmonics of a neodymium laser, the shape of pulsed signals of laser-induced thermal emission is investigated. It is found that the duration of thermal emission pulses significantly depends on the wavelength of the laser excitation, which is caused by the differences in the depth of penetration of laser radiation into the surface layer. The mentioned effect is actual, if the penetration depth of laser radiation exceeds the length of thermal diffusion in the studied material for a time of the order of the laser pulse duration. The computer modeling is carried out for the processes of pulsed laser heating and formation of thermal emission signal. The simulation results showed satisfactory agreement with the measurement results.

Research and Development in the Field of Creating Materials, Technologies and Safety Equipment

Technologies for the manufacture of microwave electromagnetic shields based on powdered carbon, foil and composite multilayer materials are presented. Technological methods for their manufacture and shielding properties are described, and the main mechanisms leading to increased shielding properties are considered depending on the manufacturing technology, composition and alternation of composite layers. It is shown that the values of the reflection coefficient of electromagnetic radiation in the frequency range 2–17 GHz for the shields considered reach a value of (–20) dB. Microwave absorbers with a reflection characteristic lower than (–10.0) dB (down to (–52.0) dB) in the frequency band 8.0–12.0 GHz are developed, and the electrophysical parameters, composition and concentration of components of the composite materials for such microwave absorbers are determined. The systems for active protection of speech information that use combined masking signals consisting of “white” noise and speech-like signals as masking signals, along with “white” noise are considered. Criteria have been developed for the approach to selecting speakers and audiences when assessing speech intelligibility to solve problems of protecting speech information and methods for experimental studies of speech intelligibility against a background of masking acoustic noise. Technologies for the formation of nanocomposites based on carbon nanotubes and nanoparticles of ferromagnetic materials are presented to increase the degree of coherence of the spin texture at macroscopic distances, increase the degree of security of electronic products to strong magnetic fields and noise immunity. It has been shown that at certain concentrations of ferromagnetic nanoparticles, micromagnetic parameters increase, ensuring high performance of active elements in magnetic fields. The role of carbon in this case turns out to be decisive. The presented results seem promising for use in the creation of anechoic chambers, partitions for separating indoor zones intended for the location of electronic devices, products for protecting humans from the effects of electromagnetic radiation in the microwave range, and the formation of combined masking signals in the form of “white” noise for devices protection of speech information, composite coatings to level out the effects of a constant magnetic field on electronic products.