Table of contents

The International Youth Conference on Electronics, Telecommunications and Information Technologies (YETI-2019) was held in Saint Petersburg on July 11 – 22, 2019. It was organized by Peter the Great St. Petersburg Polytechnic University. The YETI-2019 Conference gave an opportunity to young researchers and early-career scientists to participate in a series of lectures which reviewed the current trends and knowledge in the fields of electronics, nanoelectronics, telecommunications, optical and information technologies.

YETI-2019 collected 50 reports by over than 150 researchers from 6 countries. Conference included two keynote invited talks given by leading scientists devoted to actual problems and major advances in physics and technology. The keynote speakers were Luis Conde from Univ. Politécnica de Madrid, Spain (presentation "Plasma propulsion for telecommunication satellites") and Thomas Maurer from Universite de Technologie de Troyes, France (presentation "Active plasmonics: the rising of mechanoplasmonics and perspectives for integrating strain nanogauges into matter"). Presentations by various scientists gave an overview of recent achievements and future prospects in fields of development and design of nanoelectronic and telecommunication devices, signal processing, material science and nanotechnology. During the event, informal meetings provided an opportunity for potential partners to establish contacts, share new project ideas and start new collaborations. Certificates were awarded to a number of young participants for the best oral and poster presentations selected by the Program Committee.

List of Editors, The invited speakers, Oral Presentations photographs, Poster Session photographs, Awarding ceremony of YETI -2019 photographs are available in this pdf.

All papers published in this volume of Journal of Physics: Conference Series have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Electric thrusters are used for in-space propulsion of spacecraft for a combination of practical and economic reasons. These devices that use electric power to accelerate the mass flow of the propellant at exhaust velocities are one or two order of magnitude faster than those achieved in conventional chemical propulsion. This feature results in significant propellant savings that allows longer mission times and heavier payloads, however, the thrusts achieved are lower for important electric power consumptions. The different electric thrusters that are currently used in Europe for both in-orbit corrections and also for orbit raising to the operational orbit from the separation stage of the launcher will be introduced. This propulsion system also serves to expel these vehicles from their orbit at the end of their useful life to control the increase of space debris in Earth orbit. Additionally, the characteristics of new low-power electric engines with thrust levels in the range 0.1-10 mN and electric power consumptions below 500 W will be discussed. These are required for flight formation, orbital corrections and end-of-life disposal in the new constellations of small satellites in low Earth orbit intended for planetary internet coverage and interactive television services.

The article discusses the technology of creating a transistor using selectively-grown non-annealed ohmic contacts. As a result, a transistor was obtained, with a gate length of 1 μm. An output power density of 3.25 W / mm, an efficiency of 47% and a gain of 11 dB at a frequency of 3 GHz.

Recently, we calculated an effect of surface charges on potential barriers embedded inside a Si target. As a result, electrons and holes transport in a semiconductor target could be controlled by ionized atoms or molecules situated inside the surface adsorbate layer. Since GaAs possesses higher electron mobility than Si, in this paper we calculate the potential distribution and charge carriers motion dependences on the GaAs target surface charge value and dopant concentration. Computer simulation was implemented using the software COMSOL Multiphysics. The obtained results can help to improve a design of GaAs radiation detector, particle detector, surface charge detector, biochemical sensor, etc.

Carbon cluster coatings deposited on oxidized silicon are known to possess the capability of low-macroscopic-field electron emission. Also, such films show anomalous photosensitivity of their electric properties. Though, physical mechanisms of both these phenomena remained unclear. New experimental investigation of such coating was performed by means of scanning tunneling microscopy and spectroscopy under varied optical illumination. Its results witness in favor of hot-electron mechanism of the low-field emission capability showed by the studied cluster films.

The experimental data of the optical and electric features of the silicon nanosandwiches obtained by silicon planar technology in the frameworks of the Hall geometry are presented. Silicon nanosandwiches represent the ultra-shallow silicon quantum wells of 2nm wide that are confined by δ-barriers heavily doped with boron, which appear to be used as the phase invertors and modulators of optical THz spectra and electric signals. The negative-U dipole boron centers formation, which appear to confine the edge channels, results in the effective mass dropping and corresponding reduction of the electron-electron interaction thereby giving rise to the macroscopic quantum phenomena at high temperatures up to room temperature. The modulation phase shift of the THz electroluminescence spectrum and phase control of the longitudinal conductance are observed by changing either the magnitude of the source-drain current or the voltage applied to the external gates of the silicon nanosandwiches within the quantum Faraday effect.

Study of the dielectric parameters of different materials attracts great attention of researchers as these parameters allow knowing various characteristics of different materials and chemical substances. This article presents studies of dielectric loss tangent of albumin protein water solution. Measurements of the frequency dependence of dielectric loss tangent in the range 10–10⁶ Hz were performed. The experimental results showed non-linear frequency dependences of the dielectric loss tangent.

The structure and stability of the zigzag (6,0) and armchair (6,6) Boron Nitride nanotubes with embedded carbon atoms have been investigated in the framework of both generalized-gradient approximation (GGA) and local-density approximation (LDA) density functional theory. Carbon atoms have significant impact on both structures. The results show that embedded carbon atoms reduce the band gap and increase the density of states (DOS).

Electronic states of an electron localized in a cylindrical quantum dot with Kratzer confining potential in the presence of axial electrostatic field are considered. The dependences of the dipole matrix elements on the geometrical parameters and values of the electric field are calculated. Nonlinear optical effects such as second harmonic generation and optical rectification in this structure are studied. The electric field values, at which double resonance condition are satisfied, have been found. Optical rectification and the second harmonic generation coefficients of energy dependence curves are obtained. Specificity of the Kratzer confinement potential profile leads to vanishing of the mean displacement of the electron in intraband transitions. This fact is reflected in the behavior of optical rectification coefficient, which has a deep dip around certain values of the electric field.

The first observation of ⁵⁷Fe nuclear magnetic resonance in nanostructured magnetite, used for preparing of magnetic fluid is reported. The radiospectroscopic technique required for the reliable spin echo signal observation is discussed. The data on resonance line associated with physical properties of the material, are presented.

Methods for acoustic desensitization of fiber optic interferometer were studied as applied to the compensation interferometer (CIF) of a fiber optic phase sensor system. Materials with high mechanical loss factor were used for the fiber optic interferometer rack case. Also case acoustic conditioning measures and vibration isolation system based on steel springs were developed. Different types of fiber coating for acoustic desensitization were investigated. The best implementation provided up to 30 times (-29.8 dB) suppression of CIF undesirable acoustic sensitivity level.

An optimal configuration of the waveguide acousto-optic frequency shift modulators on the X-cut lithium niobate substrates was analyzed. The conditions for efficient excitation of surface acoustic waves (SAW) and their interaction with the guided light in integrated optical structures were found. The influence of acoustic waveguide presence and interdigital transducer (IDT) geometry and material on the SAW resonance excitation was investigated. An acoustic waveguide configuration was proposed for increasing the TE-TM optical mode conversion efficiency. A low power (about 15 dBm) high frequency modulation signal was required for full TE-TM mode conversion in the proposed modulator configuration.

Features of image formation and registration of the light-shadow boundary in flow refractometer are considered. A new design of refractometer was developed for the state control of poorly transparent and turbid flowing media containing big insoluble particles. A new algorithm for processing the image recorded on a photodiode array for determining of liquid flow parameters has been developed. A new method for contrast degree determining of the light-shadow border has been proposed taking into account features of registration and processing of optical signals. Experimental results are presented.

Thermal poling of a multicomponent silicate glass was performed in air and in argon atmospheres at various voltages, and the temperature dependences of the depolarization currents (TSDC) in the poled glasses were studied. In addition, the concentration profiles of univalent and bivalent cations in subanodic regions of the poled glasses were measured with EDS and SIMS techniques. The difference in the displacements of bivalent ions at poling of the glasses in closed and open anode configurations allowed us to identify "frozen" spatial charge relaxation peaks observed in the TSDC measurements and to relate these peaks to hydrogen and bivalent metal ions relaxation.

The influence of low-frequency acoustic vibrations on optical signals in integrated optic lithium niobate modulators is considered. It is shown that low-frequency acoustic vibrations can significantly contribute to the modulator transfer function. Characteristics of the acoustic vibrations have been observed. It is shown that these vibrations correspond to excitation of standing Lamb waves. Methods for acoustic resonance suppression have been suggested and verified.

Phase noise spectra of the microwave spin-wave photonic generator were measured for various lengths of the optical fibres. Results show that the increase in fibre length from 200 m to 4 km reduces the phase noise tending to a limit value around -146.5 dBc/Hz at a 10-kHz offset from a generation frequency of 10 GHz.

In the current paper we consider the case of the sawtooth-type of phase modulation of the interference signal argument and demonstrate a method for calculating the phase modulation step of interferometric signal in a fiber optic sensor. Two methods of calculation the modulation step are proposed: for 4-point and 5-point digital demodulation algorithm based on ordinary least squares approach. The effect of target phase on the results of calculating modulation step has been demonstrated. The dependence of the error in the calculation of the auxiliary modulation step on the amplitude of the target signal is also shown. The correspondence between analytical expressions and real modulation step of interferometric signal has been verified by means of numeric simulation.

The paper presents an analysis of optical delay lines based on coupled whispering gallery mode resonators. The induced optical delay is caused by slow light regime in high finesse resonators. The analysis is based on slowly varying envelopes approach and includes evaluation of possibilities to adjust the induced delay time. We also investigate the properties of transfer coefficient of system of coupled whispering gallery mode resonators.

In this paper the method of microcirculatory blood flow velocity registration is considered. The proposed method is based on speckle pattern analysis. The measuring setup of blood flow velocity is presented. Using this setup, blood flow velocity of a group of people under various conditions has been studied and the results of these studies are presented.

In this paper we consider a new method for improving the security of fingerprint identification systems. It is based on calculating polarimetric parameters using the Mueller matrix. This method was tested on gelatin samples that mimic real tissue with fingerprints. We showed that proposed method can increase the reliability of fingerprint sensors. In conclusion, recommendations on the modification of the laboratory setup and on the improving of the polarimetric technology are given.

This article presents a cross-correlation method for estimation the size of nanoparticles in monodisperse colloidal solutions and suspensions. The original scheme of the experimental setup for carrying out cross-correlation experiments is presented. The results of measurements for a liquid sample with dispersed particles are presented for the cross-correlation method and the classical dynamic light scattering method, in which the autocorrelation function is calculated instead of the cross-correlation function of the scattering signals. The results obtained demonstrate the fact that for highly diluted samples, autocorrelation and cross-correlation produce the same result. Since the cross-correlation method is also applicable to turbid samples, this gives it a significant advantage over the dynamic light scattering method.

A CubeSat mission is described in this paper, which deals with the space debris identification, classification and aggregation. The mission is responsible for debris observation close to the most populated orbit by on-board laser illuminator (lidar) system. An optical scheme of lidar was described. The energy balance and range of work were calculated. The architecture and properties of CubeSat are based on the multi-purpose block-modular platform «Synergy» [1].

This paper provides an overview of the basic methods for filtering images. The main sources of the noise component in the image, which should be shooted by camera based on nanosatellite, the criteria for assessing the quality of filtering and the main digital filters for image recovery are given. The comparative characteristics are presented.

Theoretical expressions describing the signal of an intermodal fiber interferometer are presented. Two methods of signal averaging are investigated theoretically: the ensemble averaging and the averaging over a "long realization". The methods are examined by conducting numerical experiments. The averaging efficiency is analyzed depending on number of realizations and the fiber length increment.

The article discusses the photometric method for recording the variation of the magnetic field. The features of registration and processing of the signal of dispersion of a magnetic wave from a moving object are established. The basic parameters of an optical sensor for detecting a magnetic wave are determined. The results of experimental studies are presented.

In this paper we address the problem of organizing a permission-conscious access to files and their metadata. A large amount of data is required to be stored and analyzed in medicine, bioinformatics, astronomy, and banking. For effective data storage, it is necessary to apply different technologies depending on the data. We have developed a system that consists of the following components: a relational DBMS to store user permissions and file metadata; an off-the-shelf distributed search engine to store activity logs; a distributed cache with permissions; a file system; a special application that interacts with all the respective components. We describe the overall architecture of our approach and discuss each component in detail. To offload database server and to speed up the permission checking we have devised a simple data caching scheme that is performed on an application server. The idea was to manually rewrite queries that are used by our application to check permissions. As a result, queries that use several tables request only non-cached tables from the database. We conclude our paper with the experimental evaluation of our system and the proposed caching approach.

The problem of geodesic distance computation in the Aircraft industry is considered in the paper. While simulating the assembly process, in some computational problems the calculation of the shortest distances between different objects is required. The aim of the work is to compare several approaches to geodesic distance numerical computation on test geometry and some of the most common joints of aircraft. The first considered approach represents graph-based algorithms. In the paper, geodesic distances are calculated in the constructed graph using Dijkstra's algorithm or its modification with binary heap. The second approach is the fast marching method, which is based on the solution of the Eikonal equation and provides efficient geodesic distance computation on triangulated surfaces.

Usage of faster than Nyquist signaling (FTN) in practice is limited by the complexity of the formation and detection devices. Optimal FTN pulses may be formed via digital non-recursive filters. One of the important parameters that affect the performance of such devices is the number of quantization levels. In this paper, the influence of the number of quantization levels for optimal FTN signals with pulse-amplitude modulation on spectral characteristics, correlation properties and the probability of error detection is investigated. It is shown that at least 64 quantization levels should be chosen to provide almost potential bit error rate performance and additional spectral quantization noise about – 40 dB for volumes of channel alphabet upto 8. Decreasing the volume of channel alphabet allows reducing the requirements for the number of quantization levels.

In this paper, simulation modelling of information transmission using spectrally efficient multi-frequency (SEFDM) signals with an amplifier and a limiter on transmission has been held. SEFDM signals have a high peak-to-average power ratio (PAPR). Therefore, we need to limit the value of PAPR to increase the efficiency of the amplifier stages of transceiver devices. An effective value for PAPR limiting has been found. For signal-to-noise ratio 7 dB, level of bit error rate reaches minimum value when the PAPR limit value is within 4.5-5.5 dB. Besides that, a comparison of the effectiveness of detection algorithms with and without feedback has been made. The results showed that detection algorithm with feedback increases the effectiveness of the multi-frequency signals application under conditions of amplitude limitation.

Due to various disturbing factors affecting data reception, telemetry information often contains outliers and lost entries. Detection of outliers and anomalies is one of the key problems of satellite data analysis. A comparison of several statistical methods of outlier detection in telemetric information on the power supply system, obtained from the "AIST" small satellites, was carried out for the purpose of increasing the accuracy of satellite's systems monitoring based on the telemetry data. The structure of telemetry from the power supply and thermal control systems of the "AIST" small satellites was analyzed. Several statistical methods for outlier detection were studied. Methods, described in the paper, allow to detect fast acting changes in telemetry data from "AIST" small satellites.

We analyze the wireless visible light simplex data transmission channel based on visible light communication (VLC) technology and determine 2 main types of errors that occur while using a modern smartphone as a receiver. We have calculated highest probable data transfer speed in our communication channel, and have developed a cyclical data transmission system with bandwidths of up to 4 kbits at a distance of 1 m, using a conventional domestic LED illuminator equipped with a modulator as a transmitter and a developed client application for an Android smartphone with a standard camera module as a receiver.

This article describes a research of receiver which is part of SDR-modem based on SEFDM-signals (Spectrally Efficient Frequency Division Multiplexing) with optimal envelopes. Three envelope types and two values of frequency spacing between subcarriers in SEFDM-signals are implemented. Influence of combined use of methods of increasing spectral efficiency on BER performance is considered. Receive algorithm of SEFDM-signals is symbol-by-symbol coherent detection algorithm.

Optical fiber sensors are of particular interest for applications in the high-voltage environments of the electric power industry due to their characteristic properties including dielectric nature, immunity to electro-magnetic interference, and small size and weight. We have studied current sensor that employs the Faraday effect in the spun fiber and signal processing based on the additional harmonic modulation of the self-consistent polarization interferometer. We replaced the traditional PZT transducer with the LiNbO3 waveguide electro-optical modulator that allowed to increase significantly the modulation frequency and to reduce the length of the fiber delay line. Original error compensation methods allowed us to achieve the accuracy of ±0.2% in amplitude in the temperature range of about 50 °C.

The paper presents the results of modeling and comparative analysis of the output parameters of thermoelectric generators with two types of geometry. The first is based on a Y-structure with a flexible substrate, the second is based on a P-structure with a flexible base. The results of modeling at different temperature conditions and the comparison of output parameters for the Y and P structures are presented. The following results were obtained: the maximum output power of the generator based on the Y-structure at ΔT = 22 K was Pmax = 14.3 μW, for the P-structure Pmax = 5.6 μW. The specific maximum output power for the Y-structure was Pmax / S = 0.54 μW / mm², for the P-structure Pmax / S = 0.21 μW / mm². Thus, a thermoelectric generator built on the basis of a Y-structure has a specific output power almost three times higher than that of a similar one with a P-structure.

A thermoelectric generator based on a SiGe superlattice was simulated using the COMSOL Multiphysics software platform. Based on the created model, a prototype generator sample can be made.The output power of a single thermoelectric generator was 0.048 μW with a temperature difference ΔT = 50 K. The generator area was 32 mm², and the thickness was 1 mm.This makes it possible to combine 100 or 500 single generators into one on a flexible basis.This type of a TEG can be used as an energy source for different type of autonomous devices, for example, sensors or microdevices.

The paper presents the study of thermoelectric properties of bismuth tellurides obtained by the method of electrochemical deposition. Measurements of electrical conductivity and the Seebeck coefficient were carried out on a NETZCH SBA 458 Nemesis® measuring installation. Based on the obtained measurements, the following conclusions were made: for samples synthesized by the method of continuous electrochemical deposition, the maximum value of the Seebeck coefficient reached α = 14 μV / K, while for samples obtained by the pulse method α = 47 μV / K. It was also noted that after annealing, the samples showed an increase in the Seebeck coefficient up to 1.5 times. As a result of analyzing the measured thermoelectric characteristics, it was concluded that the method of pulsed electrochemical deposition is more efficient for obtaining high-quality thermoelectric materials.

An assessment of the influence of the orientational frequency shift of an optically pumped quantum standard with a gas cell in the total error of the navigation systems Galileo, GPS and BeiDou satellites ephemeris is presented. A comparison of the calculated and experimental data of the time dependencies of the orientation errors for different working magnetic field values and directions is shown. For a numerical estimate of the orientational error influence on the ephemeris of different satellites, the values of the correlation coefficients between the calculated and the experimental dependencies on time are presented.

The paper describes virtual and physical experimental studies of the "rectilinear movement" locomotion of a snake robot. Software for controlling the robot movements and registering the modules movements was developed in MATLAB and Simulink. A parameterized virtual model of a snake robot was implemented in the MSC Adams. Authors propose a method for processing experimental data and demonstrate the comparison results of the virtual and physical experiments.

The article is devoted to the use of neural network methods to solve the problem of detection and classification of small objects on aerial photographs. The architectures of YOLO 2 and YOLO 3 are discussed. The training procedure is described, the obtained results are analyzed. During the work it was shown that the considered architectures can be used to solve the problem of detecting and classifying objects in images obtained as a result of aerial photography.

An algorithm of channel joint equalization and demodulation of multicarrier signals with nonorthogonal frequency spacing (spectrally efficient frequency division multiplexing, SEFDM) is proposed. It is based on DFT (Discrete Fourier Transform) and BCJR (Bahl, Cocke, Jelinek and Raviv) algorithm adapted to work with frequency samples of received signal. The performance of proposed receiver is comparable with performance of classic OFDM-signal receivers.

The article discusses the using of the rubidium – 87 quantum frequency standard for satellite navigation systems. A method for improving the parameters of the microwave excitation signal to enhance the short-term and long-term stability of the standard is proposed. The results of experimental studies are presented.

We propose to estimate the best DLL parameters for GNSS receiver through the simulation modeling. Our simulation model estimates mean standard deviation of the time synchronization error at different SNRs and with different receiver-satellite system dynamics. By using real GPS records, it was shown that DLL parameters have a significant influence on the positioning accuracy.

Impulse radio ultra-wideband system has been adopted in wireless sensor networks research due to its high performance in conditions of active influence of various noises and interferences, the presence of reflections, etc. In this paper, this system represents a transmitter based on the controller STM32 and a receiver implemented using blocks of analog and digital processing based on FPGA. This paper focuses on a realisation of an additional device that can provide the avoidance of narrowband interference in ultra-wideband wireless sensor network system to improve a value of bit error rate. For this purpose, a real device with using square low technique has been developed. According to the results of experiments this approach enables to improve a dependence of the bit error rate on the signal-to-noise ratio.

The article presents the methods for calculating the stability of the rubidium frequency standards. To implement these methods, new software has been developed. Experimental measurements of telemetric parameters of the quantum frequency standard are processed using the developed software. The stability of the prototype of the rubidium standard has been determined using the proposed new algorithms.

The article presents results of development of communication protocol for UART-like FPGA-systems. Developed communication protocol supports asynchronous oversampled signal transmission, with 4b/6b encoding for DC-balance maintaining. Algorithm of CPLD-based receiver of signals forming by this protocol is described. This development is relevant for the task of continuous transmission of several control signals over a fiber-optic line, when the use of ready-made UART devices is unjustified. The presented protocol and algorithm are easily implemented on the FPGA and can be used in devices where it is important to minimize the number of elements used. Also, the protocol contains encoding that allows the transmission of low-frequency signals along a line with DC-coupling.

This paper studies various sub-optimal versions of BCJR demodulator to examine the possibility of computational reduction. BCJR demodulator is used to deal with intentional intersymbol interference in bandwidth efficient systems. The complexity of BCJR demodulator can be reduced by using the approximation in the logarithm domain and by considering less number of trellis states instead of full states. To estimate the performance of different types of BCJR demodulator, we proposed the partial response signalling system with finite shaping pulse providing 10% gain of bandwidth efficiency. The simulation results of this study show that in the case without error correction coding the complexity of BCJR demodulator can be significantly decreased without energy losses. When low-density parity-check coding is used, it is possible to use these sub-optimal versions of BCJR demodulator, but the system may suffer additional energy losses.

The article presents the development of a new low mass-dimensional microwave frequency standard on Hg-199 ions. The optimal ion trap parameters are calculated. The new control algorithm is developed. The compact driver for trap field is constructed. The experimental data received show the decrease in size and mass while saving precision characteristics.

The problem of low positioning accuracy in the presence of interference is discussed in this work. As a way to solve this problem, spatial-temporal signal processing (STSP) is chosen when maximum likelihood (ML) optimisation criterion is used. The paper assumes that interference is a Gaussian random process with uniform (in the channel band) spectral noise density, and the additive components in each of the receiving channels are independent implementations of additive white Gaussian noise (AWGN). The commonly known form of likelihood function is transformed in the way to exclude interfering parameters of signal of interest. As a theoretical result, ML-estimator of time-of-arrival was obtained. The results are supported by a statistical simulation so that the efficiency of synthesized ML algorithm is shown. As implications for practice, the structure of navigation receiver implementation is proposed at the end of discussion.

This article describes the design of PLL synthesizer based on developed wideband hybrid VCO. In particular, the structure of such device has been defined, and its components have been chosen. It ensures the frequency range from 6 GHz to 12 GHz. The measured characteristics of PLL synthesizer are in good agreement with the calculation results. That is why developed VCO may be used for the implementation of wideband PLL system.