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Introduction. The article is dealing with the Magnetic Tracking signal path for measurement of objects’ positions in nearby places. The basic principle of the Magnetic Tracking method is based on measurement of magnetic induction of the reference magnetic fields and the calculation of the objects position based on it.Problem analysis. Big advantages of magnetic tracking technologies are the non-line-of-sight feature compared to optical tracking and high accuracy of long time measurement compared to inertial tracking. However, a very large signal range and significant distortions due to nearby metallic objects are serious drawbacks preventing magnetic tracking from being widely used.Selection and configuration of signal path components. Taking into account the requirements of uptoday microelectronics, in particular for the sensors of the Internet of Things, the signal path of the Magnetic Tracking sensors is implemented on the concept of System on Chip. Basic components of the signal path are software Programmable Waveform Generator, Programmable Gain Amplifiers and Programmable Mixer. Configurations of the components are provided by Application Programming Interface routines. Functional and model studies of the synchronous detector. Noise immune processing is based on synchronous detector. SPICE simulations and analysis of this detector are provided.Implementation of signal path of magnetic tracking. The signal converter has been implemented on the Programmable System on Chip PSoC 5LP (Cypress Semiconductor). The module CY8CKIT-059 Prototyping Kit has been used. The developed software for controlling the measurement process provides controlling the conversion mode, dynamic amplification switching, analog-to-digit converting, etc.Conclusions. The novelty of the solutions presented in the work is the combination of signal amplification dynamic switching and the noise immune processing. Reference magnetic fields are formed by actuator coils in the lowfrequency spectrum of electromagnetic waves. Signals are produced by sensor coils and are used for objects position calculation. Technologies of Magnetic Tracking are considered as high promising solutions for Virtual Reality, Augmented Reality and Internet of Things.

In the present work, a number of key aspects of the synthesis process of a set of quasi-orthogonal code binary sequences based on multiplicative compositions of optimal binary code sequences and a subset of Walsh orthogonal functions are developed and proposed. In particular, analytical expressions are proposed for estimating the parameters of periodic auto- and cross-correlation functions of quasi-orthogonal code binary sequences as a function of the structure parameters of the implemented binary sequences. From the obtained analytical expressions, the requirements to the structure of the implemented binary sequences are formulated. The simulation results of the procedure for extracting subsets of implemented binary sequences based on a system of Walsh orthogonal functions are given, examples of specific distinguished subsets that satisfy the above requirements.

In this paper there are solved two related problems: the development of the method and correspondent algorithm of code binary sequences synthesis with property of minimal level of side lobes of their aperiodic autocorrelation functions. The method is based on discrete representation of autocorrelation function in form of equations system considered on a set of integer numbers, set-theoretical representation of components of the sequence, their integer-number transformations, mutual properties and relations. There are obtained the expressions defining the dependences of absolute value of the sequence elements on a sum of levels of side lobes of aperiodic and periodic correlation functions; there are defined the necessary conditions of existence binary code sequences ; there are developed the mathematical models of binary code sequences components transformations. The efficiency criterion of each proposed algorithm is the relation of amount of all possible variants of binary code sequences of definite size l to amount of defined by proposed algorithms; the expressions for these quantities are obtained. The efficiency of proposed method and algorithms is verified by simulation results and it increases with increase of size l.

Internet of Things (IoT), a new direction in information and communication systems, has a significant impact on the development of novel electronics devices. Further progress in the field of IoT devices is conditioned by the development of sensor devices, and in particular, analog front-ends and signal converters for IoT sensors. High sensitivity and wide range applications of IoT sensors can be achieved by methods of impedance spectroscopy. Compared with other methods of physical research, impedance spectroscopy and based on it IoT sensor devices provide ease of implementation, high energy efficiency, good resolution and selectivity. In this paper, we present results of the development and model study of the impedance measuring transducer using the four-phase signal integration method. The implementation of impedance spectroscopy assumes a transition from frequency plots to plots on the complex plane, called as Nyquist plots. The data obtained in this paper are based on the SPICE (Simulation Program with Integrated Circuit Emphasis) model studding methodology, which compares small signal Alternative Current Analysis with large signal Transient Analysis. During the Alternative Current Analysis, Nyquist impedance plot are obtained in the idealized case, and during the Transient Analysis the active ReZ value and reactive ImZ impedance components are calculated for the actual parameters of the measuring transducers and the form of the activating signals. We have proposed a new solution of the impedance measuring transducer based on the four-phase signal commutation and integration method. This method consists in the formation of four informative signals, namely, the voltages $V_{Q1}$, $V_{Q2}$, $V_{Q3}$ та $V_{Q4}$, each of which corresponds to the integration results in the corresponding four phases of the activation signal. In these phases, or time t, the sign functions $A_{Q1}(t)$, $A_{Q2}(t)$, $A_{Q3}(t)$, $A_{Q4}(t)$ of synchronous detections are used: $A_{Q1}(t)=1$ at $t=[0...\pi/2]$; $A_{Q2}(t)=1$ at $t=[\pi/2...\pi]$; $A_{Q3}(t)=1$ at $t=[\pi...3\pi/2]$; $A_{Q4}(t)=1$ at $t=[3\pi/2...2\pi]$. In other time these sign functions are equal 0. Output signals of the impedance measuring transducer, namely, voltages of active $V_{RE}$ and the reactive $V_{IM}$ components are formed by adding and subtracting the numerical values of the above four voltages: $V_{RE}=V_{Q1}+V_{Q2}-V_{Q3}-V_{Q4}$; $V_{IM}=V_{Q1}-V_{Q2}-V_{Q3}+V_{Q4}$. The main units of the impedance measuring analog front-end are a synchronous quadrature detector and an integrator or filter. In comparison to traditional two-phase detection, four-phase detection we have proposed allows avoiding intermediate signal transducing, which provides a significant simplification of impedance measuring transducing. This simplification is achieved by directly integrating the instantaneous value of the $I_{Z}(t)$ current. Important dependences of the measuring transducer output voltages with four-phase integration on the operational amplifiers bandwidth are obtained. Results presented in the article are important for developing a new generation of microelectronic IoT sensor devices based on impedance spectroscopy methods. Main areas of application of such sensor devices are materials science, biochemistry, instrumentation, avionics, ecology, etc.

The approach to the development of dual-band power distribution devices with different power division ratios in different frequency bands, based on the method of a dual-frequency equivalent replacement, is considered in the article. For its implementation, an equivalent four-terminal network based on a section of coupled microstrip transmission lines is proposed in addition to the T- and —type circuits. Relations for calculating the electrical parameters of the circuit elements of these four-pole devices are obtained. The relations allow replacing the transmission line section with different values of the wave impedance in different frequency bands. The electrical length of such a section can vary and be different from π/2. Examples of modeling of non-equilateral power distribution devices with unequal branches such as two-channel balanced dividers and a ring divider (ring coupler) with power division coefficients of 2.0 and 1.0 in frequency bands with center frequencies of 2.0 and 3.6 GHz are given. Experimental measurement of characteristics of the designed models of the two devices showed good agreement between the experiment and the simulation results.

In the article the problem of the method and algorithm optimization for the disclosure of the ambiguity of distance measurements in a multiposition radar system under the condition of ambiguous measurement of distance to the controlled object by each of the radar stations of this system is considered. This feature is determined by the use of modulating code binary sequences for secrecy and noise immunity. By criterion of optimality accepted the number minimization of possible options for selection when solving an integer task of ambiguity disclosure. A method and an algorithm are presented, the complexity of which in implementation does not depend on the number of radar stations in a multiposition system. It is shown that the probability of correct disclosure of ambiguity increases with an increase in the number of radar stations in the system.

The paper considers the problem of synthesis of code binary sequences (CBS) with optimal aperiodic autocorrelation functions according to the criterion of at least 4 levels of side lobes of the corresponding aperiodic autocorrelation function. The properties of algebraic operations in the finite fields are used to represent the above code binary sequences, their elements, and the convolution. The matrix, which determines the dependence between signs plus and minus of the elements of the binary sequences, also provide the possibility of establishing interrelation of the above-mentioned levels of side lobes. For the sequences of small dimensions, as an illustration, the analytical expressions of the specified relationship are given. The algorithm is substantiated and suggested, an example of synthesis of code binary sequences is given.

The work presents the concise results of developing a measurement devices set (named RETwix), which are universal hardware-software tools for conducting laboratory research. The complex universality consists in the fact that practically anything may be the subject of study, including electronic devices and various electric, temperature, chemical or biochemical processes. The RETwix complex incorporates UA-LAB (Universal Analog LABoratory) unit, CV-LAB (Capacitance & Voltage LABoratory) unit and software.

This paper shows the practical use of genetic algorithm (GA) in the search of novel multi-phase signal-code sequences that can be used in radar systems as well as communications. A few examples of such sequences and their characteristics compared to well-known signals and codes are presented

The method of increasing the object detection probability by system of multispectral monitoring is developed. The functioning of the multispectral monitoring system with proposed method of movable images fusion is investigated. Fusion of information from visible and infrared channels of the monitoring system by the developed method of data fusion and detection of moving objects on the fused video signal by developed algorithm of motion detection were carried out. The results of experiments confirm that the probability of detection increases, recognition and identification of moving objects by the multispectral monitoring system are achieved due to improved informativeness of formed image with the developed method.

A simple circuit for dual-frequency decoupling and matching of two antennas with mutual coupling is proposed. Such scheme allows providing a decoupling at two closely located operation frequencies and can be made by a microstrip technology. Some of circuits together with methods of their calculation for the realization of dual-frequency reactances which are the components of a decoupling scheme and for the input matching realization are proposed. The results of simulation of the decoupling and matching circuit for two monopole antennas working at the frequencies 2.4 and 2.6 GHz confirm a possibility to use the offered circuits and calculation methods at a small value of the frequency ratio.

A complex function is proposed as a template for the fusion of visual and infrared images such that one of the partial images is chosen as the real part and the other one as the imaginary part of the complex function. The amplitude and the phase of the complex function are two generic algorithms for the synthesis of the amplitude and phase images. Several no–reference quality indices are measured for fused amplitude and phase images and compared to those obtained for the partial images and the images fused with the average fusion, Laplace pyramid transform, and modified discrete wavelet transform methods for four observation scenes.

In this paper an analysis of known methods of image informativeness is carried out. It was found that in many cases existing methods are not working correctly, in particular, give an inflated evaluation, which is not consistent with human visual perception. A new method that allows us to evaluate the image informativeness more adequately the image informativeness is proposed. The adequacy of the results, obtained with the help of the proposed method was confirmed by a sociological survey of a group of 30 respondents who gave an expert evaluation of the informativeness of test images. As a result, it was proved experimentally that the proposed method gives a more correct evaluate of the image informativeness.

The paper considers the problem of synthesis of code binary sequences (CBS) with optimal aperiodic autocorrelation functions according to the criterion of at least 4 levels of side lobes of the corresponding aperiodic autocorrelation function. The properties of algebraic operations in the finite fields are used to represent the above code binary sequences, their elements, and the convolution. The matrix, which determines the dependence between signs plus and minus of the elements of the binary sequences, also provide the possibility of establishing interrelation of the above-mentioned levels of side lobes. For the sequences of small dimensions, as an illustration, the analytical expressions of the specified relationship are given. The algorithm is substantiated and suggested, an example of synthesis of code binary sequences is given.

The paper presents the results of the development of a modified analytical model of the periodic autocorrelation function of code binary sequences for the wireless data transmission systems signals synthesis. The model is based on a discrete representation of the autocorrelation function of sequences in the form of a system of equations given on the set of integers, the theoretical-multiples interpretation of the components of the sequences, their integer transformations, mutual properties and relations. The analytical expressions of the transformations of the components of the sequences are developed and presented. The dependences of the module of the sum of the elements of the sequences on the sum of the levels of the side lobes of their autocorrelation function are obtained. The necessary conditions for the existence of the sequences are defined and formulated. Example of the code binary sequence synthesized on the basis of the developed model is given.

The evaluation of the fusion methods of multispectral images in terms of their use for improving the multispectral monitoring systems efficiency is conducted. By image fusion in brightness with simultaneous formation of complex image in pseudo colors with subsequent correction of the colors gamut, it is possible to achieve improved monitoring of objects under difficult observation conditions.

The paper proposes an approach, identifies and formulates the necessary condition for the existence of a discrete coded sequence irrespective of the dimension of its alphabet, proposes a model of reflections and transformations of ordered sets of elements of a sequence, an example of a binary sequence with an optimized aperiodic autocorrelation function obtained based on the proposed approach.

Approach to calculation of tolerance deviations to electrical parameters of circuit elements of microstrip devices on the basis of passive symmetric reactive two-port networks is offered in the work. The tolerances calculation is based on the using of input reactances of partial two-pole networks received as a result of even-odd excitation of the two-port network. Values of these input reactances are unambiguously connected with values of working parameters of the main options of functional using of the device. Therefore, for the preset deviations of working parameters it is possible to define tolerances of input reactances. On the other hand, using analytical connection of input reactances with electrical parameters of circuit elements of partial two-pole networks, it is possible to express the deviations of input reactances through the deviations of these parameters. Equating of both results gives the chance to define tolerances values of elements parameters at which working parameters of the device don't leave the preset limits. Offered approach is expedient to using at the design of device at a stage of parameters calculation of its circuit elements. Uses of approach is examined on the example of calculation the tolerance deviations of the device on the basis of the coupled microstrip lines segment intended for a phase delay of a signal.

The method of synthesis of coded binary sequences with given simple dimensionality and levels of side lobes of the periodic autocorrelation function is developed and proposed. The method is based on the use of the properties of cyclic maps, d functions and comparisons of the theory of numbers. An example of the synthesis of an optimal binary sequence of dimension 23 is given.

An equivalent representation of a circuit formed by coupled lines section with cross-symmetrical loads and additional reactive elements is suggested in the form of partial one-port networks with in-phase or antiphase excitation. Analytical relations for the electrical parameters calculation of elements of the circuit, which enables one to implement devices with dual-band operation mode, have been obtained based on the input impedances of these one-port networks. The examples of application of relations obtained for the simulation of dual-band phase shifters with fixed phase difference, impedance transformers and bandpass filters are provided. The simulation results are confirmed by experimental investigations of these devices.

The basic approaches of parametric analysis of impedance measuring front-end on the base of SPICE modeling are considered in paper. The method for impedance analysis using the mathematical functions of real Re and imaginary Im signal components is applied. By means of this functions it is possible to investigate the frequency dependences of the corresponding values of the active ReZ and the reactive ImZ impedance, and, thus, to plot the Nyquist diagram. In this article, the galvanostatic measurement method is used, which is on the base of the determination of the ratio and phase delay between the voltage and the harmonic current with the specified amplitude and frequency. As a result of simulation, the possibility of significant increase of the measurement transformation accuracy is found by means of modifying the input circuits of the impedance measuring front-end.

This paper considers the problem of forming formal statements regarding the formal parameters of binary code sequences, mathematical model transformations, their properties and the order of operations while optimizing the sequence on the criteria of minimal side lobes. The results of modeling are shown as a group of optimized binary code sequences.

In this work the results of research of microwave motion sensor on the basis of the integrated antenna-oscillator are presented. The option of realization of such sensor with modulation of the electromagnetic oscillations reflected back from the explored object is represented. Influence of the change of frequency of generating oscillations, caused by modulation mode, on forming of sensitive area of the sensor is shown.

Approach to development of calculation methods of passive microstrip devices with symmetric structure based on the input impedances of partial schemes received by use of even-odd excitation of symmetric multiport are offered in the work. The expressions relating the input impedances of partial schemes of the transforming four-pole circuit and the directional four-port circuit with their scattering parameters are given. Features of usage of input impedances method for the design of different microstrip devices, including those on the basis of coupled line segments are considered.

Conditions ensuring the dual-frequency operation of directional couplers with two symmetry planes were defined, and an approach to the development of methods for calculating the electric parameters of coupler elements was considered. This approach is based on using input impedances of partial two-pole networks of the co-phase (symmetrical) and opposite-phase (asymmetrical) excitation. Examples of using such approach to the classical circuit of double-stub directional coupler and to its modification with two additional reactive elements were also presented.

The paper considers increasing of the multispectral images resolution using arithmetic combinations based on the Brovey transform method to improve segmentation of multispectral images by k-means clustering algorithm.

This paper presents the application of equivalent replacement method for the development of dual-band microwave power distribution devices with arbitrary power division ratio in different frequency bands. The expressions allowing to replace with the equivalent circuits of T-type and P-type a transmission line segment having a different values of characteristic impedance and electrical length at different frequencies are received. For the obtaining of such expressions the method based on the input reactances of reduced partial circuits of even-mode and odd-mode excitation is offered for using. Expression for determination of parameters of the loaded line segment which is used for realization of a reactance with two values of resistance at different frequencies is received also. The examples of calculation and simulation of a dual-frequency power divider and rat-race coupler with power division ratio equal to 2 and 1 at frequencies 2 and 3.6 GHz are given.

Method for calculation of electrical parameters of dual-band digital phase shifters, which are based on the switchable paths and provide the preset values of differential phase shifts in frequency bands, is offered in work.

In this paper, the different algorithms of contrast and brightness improvement are presented and compared. The median filter together with equalization algorithm is analyzed for the thermal image contrast improving with the influence of white noise and impulse noise.

Developed modification data clustering algorithm for multispectral image segmentation based on their specific opportunities to allocate individual objects or spatial domain with specific spectral properties.

In the paper improved matrix model of the subpixel imaging process by optical scanner is proposed. The possibility of the resolution images increasing up to 2 times relatively a simple image formation is shown. A comparative evaluation of the noise immunity of proposed algorithm is conducted.

A new approach to analytical calculation of directional couplers that have two symmetry planes, which is based on using input impedances of co-phase (symmetrical) and opposite-phase (asymmetrical) partial two-poles is suggested. Examples of using such approach for calculations of directional couplers on the basis of a coupled lines segment with three directivity types are discussed.

Determination of the acceleration of the dynamic microobjects movement, the motion of which is accelerated uniformly or non-uniformly is an important task in television measuring systems. Most of existing measurement systems usually have a small range of determination of the acceleration with a short period of growth.

The methods of signal analysis of photosensitive array and related conventional methods of digital filtering of time series is essentially the same as those in other areas of science and technology. Subpixel processing are peculiar, perhaps, only the inverse filtering procedure, providing high resolution of single reflections with limited pixel size photosensitive matrix. Combination of two matrix counts shifted by half a pixel, followed by deconvolution, resolution can increase in two times.

The paper deals with modern problems of remote sensing and the possible ways to improve the spatial resolution. New ways of data capturing that allow sub-pixel technology using with to take pictures a higher spatial resolution are described. Theoretical and experimental results show that the proposed method increase resolution of satellite images.