Protective encoding by code based on code signal feature (CSF) is one of the ways to provide reliable information channel operation in noisy environments. The paper describes possible additional requirements imposed on code word set for... more
Protective encoding by code based on code signal feature (CSF) is one of the ways to provide reliable information channel operation in noisy environments. The paper describes possible additional requirements imposed on code word set for CSF-based code, which guarantee a certain level of noise immunity in terms of minimal amount of noise impulses, which lead to false reception or protective failure. It is shown, that the imposed requirements indirectly generate alternative set of inter-symbol distances, which allow improving information channel noise immunity under the influence of highly intensive noise.
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This article describes calibration and measurement methods for multiport reflectometers of a special form; these methods use statistical processing of data drawn from measurement legs in the multiport reflectometers, using the method of... more
This article describes calibration and measurement methods for multiport reflectometers of a special form; these methods use statistical processing of data drawn from measurement legs in the multiport reflectometers, using the method of maximum likelihood. The calibration procedure uses an adaptive Bayesian approach to selection of unknown loads without the use of precisely calibrated loads. The measurement method makes it possible to obtain, with the multiport reflectometer, the complex reflection factor of the loads under investigation. The use of microwave-circuit analyzers using multiport reflectometers with at least eight measurement ports has great promise.
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This paper describes a non-contact laser device for measuring the parameters of vibrations; its technical characteristics and domain of application are discussed. The accuracy achieved in measurements is 0.01 μm for linear displacement,... more
This paper describes a non-contact laser device for measuring the parameters of vibrations; its technical characteristics and domain of application are discussed. The accuracy achieved in measurements is 0.01 μm for linear displacement, and 0.0001 μm for the amplitude of spectral components of vibrations in the audio-frequency range.
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OPTIMIZATION OF MULTI-PORT REFLECTOMETERS usiric MATHEMATICAL SIMULATION A pmmeter optimization method of a multi-port reflectometer (MPR) for measuremcmnts in narrow and wide wavelength ranges using mathematical modeling end statistical... more
OPTIMIZATION OF MULTI-PORT REFLECTOMETERS usiric MATHEMATICAL SIMULATION A pmmeter optimization method of a multi-port reflectometer (MPR) for measuremcmnts in narrow and wide wavelength ranges using mathematical modeling end statistical simulation is described. A technique for optimal control of measurements in order to decrease the undesirable effect of probe gains on measurewnt accuracy is proposed. The corresponding software bekg developed for IBWAT-compatible is intended.
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Research Interests: Computer Science, Algorithms, Artificial Intelligence, Biomedical Engineering, Electroencephalography, and 15 moreBrain Computer Interface, Linear models, Genetic Algorithm, Feature Selection, Brain, Evoked Potentials, Discriminant Analysis, Humans, Computer Simulation, Linear Discriminant Analysis, Electroencephalogram, High Dimensionality, Fingers, Electrical And Electronic Engineering, and Linear discriminate analysis
DVB-T2 is a widely adopted standard for digital data transmission systems. The standard defines multi-cascade encoding of the input signal. Noise immunity of the transmitted data is ensured by combination of Bose-Chaudhuri-Hocquenghem and... more
DVB-T2 is a widely adopted standard for digital data transmission systems. The standard defines multi-cascade encoding of the input signal. Noise immunity of the transmitted data is ensured by combination of Bose-Chaudhuri-Hocquenghem and Low-Density Parity-Check codes with subsequent COFDM modulation. The work considers inclusion of the additional stage to the existing code cascades. This stage provides protective encoding by the code with code signal feature. The research demonstrates that introduction of protective encoding improves power efficiency of the system and decreases signal-to-noise ratio, required to achieve a certain level of bit error rate. The work also shows that the code signal feature-based code simplifies encoder and decoder structure and replaces COFDM modulation by a light-weight pulse-position modulation.
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Increasing amounts of information transmitted-by-the-air provides an expansion of the data transmission bandwidth and an increase in the requirements for transmitting and receiving devices. This problem can be solved with the help of... more
Increasing amounts of information transmitted-by-the-air provides an expansion of the data transmission bandwidth and an increase in the requirements for transmitting and receiving devices. This problem can be solved with the help of software defined radio systems (SDR).
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Synchronization of all constituent units must be provided in all digital data transmission systems with a serial synchronous interface, primarily of encoding and decoding devices. This work investigates the method and algorithms of... more
Synchronization of all constituent units must be provided in all digital data transmission systems with a serial synchronous interface, primarily of encoding and decoding devices. This work investigates the method and algorithms of information reception and transmission based on using of code signal feature that do not require the application of error-correcting codes and special measures for synchronization ensuring. Special feature of the developed algorithms is the representation of each discharge symbol of the primary error-correcting code in the form of binary sequences, transmitted over a communication channel in the form of pulses series conditionally infinitely small duration rigidly interconnected by fixed time intervals that are multiple to certain time delay. The paper shows that the suggested method of transmission has the properties of self-synchronization, and significantly increases the information reliability of the system.
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The aim of this work is consider the application of the uncertainty method for error calculation in modern automatic network analyzers based on the multi-port correlator. The expressions for uncertainty estimates of the both types A and B... more
The aim of this work is consider the application of the uncertainty method for error calculation in modern automatic network analyzers based on the multi-port correlator. The expressions for uncertainty estimates of the both types A and B are discussed. The expressions for error matrices estimators defining the MPC calibration and measuring accuracy are obtained. It is shown that this method can be effectively used for error estimation of the modern measurement systems in microwaves. The effectiveness of the uncertainty method is illustrated by the considered example of the combined multi-port correlator (CMC), which operation is compared with the conventional multi-port reflectometer using the computer simulation method. The resultant uncertainties of the complex reflection coefficient achieved by CMR are considerably low the uncertainties inherent to conventional multi-port reflectometer. The promising of CMR use for microwave parameter measurement are underlined.
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The self-organizing algorithm of Kohonen is well known for its ability to map an input space. That technique is named as Self-Organizing Map — SOM. A SOM can be trained in a short period of time with a few optimization techniques such as... more
The self-organizing algorithm of Kohonen is well known for its ability to map an input space. That technique is named as Self-Organizing Map — SOM. A SOM can be trained in a short period of time with a few optimization techniques such as “winning” neurons search scope limit. In this paper we propose alternative options for improving the SOM learning speed. The basic idea of the proposed modification is based on the fact that learning is based on the method of a “winner” quick search until you reach so-called “breakthrough” epoch of learning. When a “breakthrough” epoch is reached it can be assumed that new “winner” neuron is always located at the place of the old one that allows the search to finish. This modification can significantly reduce the neuron-winners search time.
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The purpose of the paper is to propose a fully automated method of volume assessment of structures within human brain. Our statistical approach uses maximum interdependency principle for decision making process of measurements consistency... more
The purpose of the paper is to propose a fully automated method of volume assessment of structures within human brain. Our statistical approach uses maximum interdependency principle for decision making process of measurements consistency and unequal observations. Detecting outliers performed using maximum normalized residual test. We propose a statistical model which utilizes knowledge of tissues distribution in human brain and applies partial data restoration for precision improvement. The approach proposes completed computationally efficient and independent from segmentation algorithm used in the application.
The work considers an information channel (IC), which consists of encoding devices, decoding devices and communication channel (CC). Two IC types are analysed: IC with transformations and generic IC, where both transformations and... more
The work considers an information channel (IC), which consists of encoding devices, decoding devices and communication channel (CC). Two IC types are analysed: IC with transformations and generic IC, where both transformations and erasures are possible. To provide high level of the IC noise immunity, it is suggested to use cascade coding with an error-correction code on the first stage and code based on code signal feature (CSF) on the second stage of the encoding. The paper gives an overview of the CSF-based code, describes its properties, explains encoding principles and provides the structural schemas of encoding and decoding devices. The mathematical model for each IC type is created. Both models assume the influence of the random additive pulse noise with Poisson distribution of impulses and Gaussian distribution of impulse amplitudes. The noise influence analysis is performed. As a first step, the formulas to calculate CC statistics are deduced. As a second step, possible IC r...
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This article presents a mathematical model of the combined multiport correlator that allows to transmit data in a wide frequency band, which is very important for modern software defined radio systems. High efficiency of CMPC was... more
This article presents a mathematical model of the combined multiport correlator that allows to transmit data in a wide frequency band, which is very important for modern software defined radio systems. High efficiency of CMPC was confirmed with the help of the numerical experiments. Theoretical conclusions are confirmed by the computer simulation being carried out.
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The paper investigates the estimation errors given by the angular velocity of rotary tables that are based on the angle sensor, the angular velocity sensor, and the tangential as well as centripetal acceleration sensors. Rotary tables are... more
The paper investigates the estimation errors given by the angular velocity of rotary tables that are based on the angle sensor, the angular velocity sensor, and the tangential as well as centripetal acceleration sensors. Rotary tables are used in the production and research of angular rate sensors, units and systems based on them. The aim is to investigate the possibilities of increasing the accuracy of the rotary table angular velocity estimation due to the aggregation of information about angular velocity sensors of different physical nature. To achieve these goals the objectives of the study of the error probability density distributions for sensors of different physical nature are stated. The article describes the design of the rotary table bench, including the angle, angular velocity as well as tangential and centripetal acceleration sensors. Expressions for estimators of the angular velocity basing on the readings of each sensor are given. It is shown that the least square est...
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Providing a high level of informational reliability and, firstly, noise immunity is the main problem of information channel (IC) synthesis. Quantitatively noise immunity is measured by reception outcome probabilities: probability of... more
Providing a high level of informational reliability and, firstly, noise immunity is the main problem of information channel (IC) synthesis. Quantitatively noise immunity is measured by reception outcome probabilities: probability of correct reception, false reception and protective failure. The most urgent problem of the IC noise immunity improvement is minimization of the false reception probability. When IC is under the influence of high intense noise, this problem is usually solved by cascade coding usage with application of code with code signal feature (CSF) at the final stage of encoding. The structure of the code with CSF and its features were described in details in previous works of the authors. This paper contains mathematical models of coding and decoding procedures for code with CSF. Also it is shown that despite the code with CSF is a combinatorial non-linear, inseparable code with a constant weight by the structure, its coding and decoding algorithms can be mathematica...
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A new universal combined multi-port correlator calibration procedure based on estimation of unknown model parameters by the maximum likelihood method is proposed. The main advantage of this calibration is that it can be carried out... more
A new universal combined multi-port correlator calibration procedure based on estimation of unknown model parameters by the maximum likelihood method is proposed. The main advantage of this calibration is that it can be carried out without calibration standards with precisely known reflection parameters. The only parameters that implied to be known are the distances from the reference plane to the multi-port probes and frequency of the reference generator. Nevertheless, the accuracy of calibration is comparable with the conventional MPR calibration techniques, which use the precise calibration kits. The comparison results of the achieved accuracy by the conventional and proposed calibration procedures obtained by the computer simulation are given. They confirm the made theoretical conclusions.
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A new technique for backscattered signal parameter estimation of a radio frequency identification system with an arbitrary multi-port receiver based on solution of its quadric equations by the maximum likelihood method is proposed. The... more
A new technique for backscattered signal parameter estimation of a radio frequency identification system with an arbitrary multi-port receiver based on solution of its quadric equations by the maximum likelihood method is proposed. The proposed technique has no need in precise preliminary calibration of MPR ports' gains. The calibration procedure is carried out in parallel with the measuring one that permits to simplify considerably the MPR design. The results of computer simulation confirming the theoretical conclusions are given.
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A new topology of piezoresistive pressure sensor signal conditioner based on the alternative current loop is proposed. The mathematical model of this sensor is discussed and its advantages are revealed. The optimal procedure for model... more
A new topology of piezoresistive pressure sensor signal conditioner based on the alternative current loop is proposed. The mathematical model of this sensor is discussed and its advantages are revealed. The optimal procedure for model parameter estimation based on the maximum likelihood method is derived. The results of computer simulation confirming the theoretical result are given.
The analysis of modern techniques used for automatic measurements in microwaves is given in the paper. The advantages and drawbacks of two mainstream automatic network analyzers are discussed. The conventional measuring technique based on... more
The analysis of modern techniques used for automatic measurements in microwaves is given in the paper. The advantages and drawbacks of two mainstream automatic network analyzers are discussed. The conventional measuring technique based on vector voltmeter (VV) is very accurate, so it is taken as a basis of almost all commercially available meters. However, it is based on the frequency down conversion; therefore, these meters include a large amount of expensive equipment, since they are very complicate and expensive. The second method of multi-port reflectometer (MPR) uses the power detectors for measurement of the output signals. Theoretically the equipment of this method is less complicated and expensive. But the calibration of the MPR is very difficult since it requires a large kit of precisely known standards that are available only for a few instrumentation engineers. That is why MPR did not are not widely used and are not commercially available. The special case of MPR is the m...
The peculiar features of angular velocity and linear acceleration micromechanical transducers application for implementation of primary information sensors arrays used in automatic control systems of helicopter-type aircraft are... more
The peculiar features of angular velocity and linear acceleration micromechanical transducers application for implementation of primary information sensors arrays used in automatic control systems of helicopter-type aircraft are considered. Difficulties arising from the replacement of previously used inertial transducers by the modern transducers of different type are described. The techniques for sensor array design and its subsequent testing allowing one to take into account and eliminate the emerging difficulties are proposed.
The work is devoted to describe our automated technique of tumour and neoplasm volume assessment on brain MRI. First we proposed adaptive processing of dynamic local surroundings by estimating of local entropy. Secondly, the investigation... more
The work is devoted to describe our automated technique of tumour and neoplasm volume assessment on brain MRI. First we proposed adaptive processing of dynamic local surroundings by estimating of local entropy. Secondly, the investigation of volume assessments directly is ground on the proposition to check extent of interdependency between adjacent slices. The overall approach uses double-criterion principle. The first one estimates cross correlation, the second one is based on Max-dependency principle. Obtained results prove consistency of the implemented approaches.
The article presents an algorithm for planning the trajectory which goes exactly through two given points: the initial and end points. By complicating the structure of the neural network, we can plan the trajectory that will go through a... more
The article presents an algorithm for planning the trajectory which goes exactly through two given points: the initial and end points. By complicating the structure of the neural network, we can plan the trajectory that will go through a specified number of points with regard to additional conditions. It is obvious that with the increase of the problem complexity, the accuracy of the solution to the problem decreases. The suggested recommendations reduce the possibility of errors in the neural network solutions.
This article is devoted to the laser system of automatic landing of unmanned aerial vehicles, its principles and operating modes. The algorithm of the system operation in all modes is described: from the beginning of operation to touching... more
This article is devoted to the laser system of automatic landing of unmanned aerial vehicles, its principles and operating modes. The algorithm of the system operation in all modes is described: from the beginning of operation to touching the aircraft of the runway.
The reader of the passive radio frequency identification system (RFID) is proposed based on automatic network analyzer (ANA), commonly used to measure the complex reflection coefficient (CRC) of microwave devices. This architecture of the... more
The reader of the passive radio frequency identification system (RFID) is proposed based on automatic network analyzer (ANA), commonly used to measure the complex reflection coefficient (CRC) of microwave devices. This architecture of the reader allows one to overcome the main problem of passive RFID, namely, the signal of the reader transmitter penetration into its receiver that blocks the weak signal of a radio tag. A vector ANA based on a direct frequency down-conversion of the output signals of combined multi-port reflectometer (MR) measuring ports is proposed for use in the reader of a passive RFID system. Optimal algorithms for estimating the unknown module and phase of the radio tag signal as well as gains of the measuring channels of the proposed RFID reader are developed, which ensure high accuracy, reduce random measurement errors and basic systematic calibration errors. The experimental setup design of the combined MR is described. The results of the RFID system simulatio...
A low cost and reliable fire detection and alarm sensor is proposed. It architecture uses the current loop circuit constructed in the form of nickel wire divided into several segments. The voltages are taken from the each segment and... more
A low cost and reliable fire detection and alarm sensor is proposed. It architecture uses the current loop circuit constructed in the form of nickel wire divided into several segments. The voltages are taken from the each segment and analyzed using a microprocessor. The growth of temperature associated with the occurrence of fire leads to an increase in the resistance of the corresponding wire segment and an increase in the amplitude of the signal taken from this section. Continuous monitoring of the voltage amplitudes taken from the wire segments makes it possible to determine the location of the fire that has arisen and to include an automatic fire extinguishing system. The procedure for voltage amplitude estimation is described and technique based on optimal design of experiments that allows one to simplify drastically the solution of obtained equations with microprocessor is given.
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In this paper we study discrete models of ICs with memory, transition probability graphs for such models are being built, including the ones where erasure errors were taken into consideration. The probabilities of correct symbol reception... more
In this paper we study discrete models of ICs with memory, transition probability graphs for such models are being built, including the ones where erasure errors were taken into consideration. The probabilities of correct symbol reception for given channel alphabet are being evaluated. New variants of models that reflect the processes of signal transmission and processing in actual digital (code) ICs in a more precise fashion are being offered.