Digital Data Transmission Research Articles

Green technologies use in the smart grid construction in rural power supply systems

The article considers the using intelligent controls possibility in low-voltage rural electric networks to minimize the unbalance modes consequences. The proposed technology includes the digital data transmission compilation on the electrical energy parameters with a new balancing technical means the electrical network operating mode. Digital feedback is provided for changes the balancing device (BD) parameters by the unbalancing power consumption changing level. Based on the developed methods compilation, software for calculating unbalancing modes has been created, which makes it possible to assess the currents and voltages unbalancing effect on the power quality and its additional losses change. The “green” technology proposed version, which increases the economic and the electric energy environmental safety use in the rural electric power industry, contains a new constructive solution for the balancing device implementation. The proposed technology was tested on the measurement data basis in existing electrical networks. Based on the MALAB technologies use, changes studied indicators visualization in the before and after BD integration in the electrical network was carried out and its analysis was makes. Used on the “neural networks” MALAB technology, a preventive assessment of the unbalancing power consumption events development in the investigated operating electrical network is presented, as well as the proposed technology effectiveness assessment was carried out.

IoT-платформа для вібраційної діагностики промислового обладнання

The subject of study in the article is a digital platform for vibration diagnostics of industrial equipment. The aim is to increase the informativeness of vibration diagnostics processes of industrial equipment by developing and implementing IoT-oriented solutions based on the concept of intelligent sensors and actuators according to the IEEE standard 1451.0-2007. Tasks: to substantiate the feasibility of using platform-oriented technologies for vibration diagnostics of industrial equipment and choose a cloud service for the implementation of the platform, to develop software and hardware solutions for IoT-platform for vibration diagnostics of industrial equipment; calibrate the vibration diagnostic system and check the accuracy of the measurement. The methods used are microservice approach, multilevel architecture, methods for assessing the condition of equipment by vibration indicators. The following results were obtained. The Microsoft Azure IoT platform, which provides the infrastructure for creating and managing cloud applications, was chosen as the cloud computing platform for the industrial equipment vibration diagnostic system. Azure Internet of Things Suite is a Microsoft Azure IoT service designed to integrate and organize data flows, analyze, and present data in a format that helps people make informed decisions. The architecture of the IoT-system of vibration diagnostics of industrial equipment developed and presented in the article is three-level. The level of autonomous sensors provides reading of vibration acceleration indicators and through the digital wireless data transmission channel BLE transmits data to the Hub level, which is implemented based on a single-board microcomputer BeagleBone. The computing power of BeagleBone provides work with artificial intelligence algorithms. At the third level of the server platform, the tasks of diagnosing and predicting the state of the equipment are solved, for which the Dictionary Learning algorithm implemented in the Python programming language is used. Conclusions. Tests of the IoT system for vibration diagnostics of industrial equipment were performed using a special stand, which allows the calibration of sensors and verification of the accuracy of the measuring system. The correctness of the entire system is confirmed by the coincidence of expected and measured results. The direction of development of the IoT-system for vibration diagnostics of industrial equipment is the development of additional microservices, which will add the possibility of using modern artificial intelligence technologies for complex diagnostics and forecasting of equipment status.

Fused Deposition Modeling‐Based 3D‐Printed Electrical Interconnects and Circuits

Multimaterial 3D printing in electronics is expanding due to the ability to realize geometrically complex systems with simplified processes compared with conventional printed circuit board. Herein, the feasibility of using a copper‐based filament to realize 3D circuits with planar and vertical interconnections is presented. The resistivity of the tracks (1–3 mm wide) is studied with reference to printing parameters and orientation. Using lateral infill for 1 mm tracks offers lower resistance compared with longitudinal infill (≈75%). For wider tracks, the effect of infill orientation on resistance diminishes. The evaluation of tracks embedded in polylactic acid shows a drop in maximum current (to ≈11 mA) compared with exposed tracks (≈16 mA). There is no observed correlation between electrical performance and number of embedding layers. However, a significant correlation is observed between the tracks’ resistance and the amount of time the filament remains in the heated nozzle. This in‐depth study leads to optimum resolution to realize conductive tracks of 0.67 mm thickness and the first integration of fused deposition modeling (FDM)‐printed conductive traces with small‐outline integrated circuits to open a pathway for higher‐density 3D printed circuits. Finally, the transmission of digital data by a 3D printed circuit is demonstrated.

Asymmetric Optical Wavelength Switch Based on LCoS-SLM for Edge Node of Optical Access Network

A novel design of optical wavelength switch, based on an asymmetric switching architecture for edge node implementation, is presented in this paper. Compared to previous research for optical core transport network applications, the proposed work has a unique aspect to build dynamic multicasting and spectral equalization, vital functionalities for optical wavelength switch in the edge of optical access networks. An optical wavelength switch was experimentally implemented and evaluated in a 4 × 16 switching architecture to demonstrate the concept. This dynamic multicasting and spectral equalization were achieved by utilizing liquid crystal on a silicon spatial light modulator (LCoS-SLM) device. An optimal design of computer-generated holograms (CGHs) through an improved GS algorithm was used to perform the beam steering and wavelength switching. A variety of wavelength switching scenarios has been experimentally evaluated. The measurement results showed an average insertion loss of around -12.5 dB, and the calculated crosstalks were all less than -28 dB. Its applications in digital data transmissions were evaluated to achieve a transmission speed larger than 2.5 Gbps. The eye diagram measurement results showed that most wavelength switching scenarios have nearly bit-error-free transmission. The scenario includes the multicasting with spectral equalization within the proposed asymmetrical switching architecture.

Nonlinear Noise Modeling: Using Nonlinear Circuit Simulators to Simulate Noise in the Nonlinear Domain

Noise is a random signal, a perturbation of dc bias and RF signals. It is usually necessary that digital electronics provide a low bit error rate or error vector magnitude to guarantee the reliable digital transmission of data. Microwave electronics are commonly expected to amplify or mix these digital signals with high linearity and without adding significant noise, which translates to the requirement of a 10-dB signal-to-noise ratio (SNR) in a communication system. In the case of a nonlinear circuit, it might not always be clear how noise could be an issue at all. Firstly, the signal is several tens of decibels larger than in the smallsignal domain. Secondly, one might consider nonlinear distortions to be the first limiting factor.

Utilization of huffman coding for weather buoy system using long-range communication

Weather buoy is an instrument used to gather weather and ocean parameters and is deployed in the world’s ocean. Monitoring sensors are used for gathering weather and ocean parameters. The data is transmitted through long-range (LoRa) communication system. Transmission in a weather buoy is conventional by sending non-compressed input data, or via digital signal processing that compresses and decompresses the gathered data in a real-time transmission. In this paper, the Huffman Coding algorithm was used for minimizing and compressing codes. It was utilized to ensure the transmission of digital data from the transmitter of the weather buoy to the receiver part. The fixed-length codes with different bit numbers generated by the transmitter reduced the length of the messages from an average of 2000 bits per second to 480 bits per second per message through the use of the Huffman Coding algorithm. The evaluated result consists of 125 transmissions and encountered 7 non-compressed data. Therefore, the text file compression or the accuracy is 118/125 or 94.4%. The Huffman Coding approach was found to be an optimal solution for data transfer as it can transmit compressed input data. It is about 13 seconds compared to a 6-minute time delay with occurrences of data traffic. It is for the data which are non-compressed and transmitted as it is. It shows significant improvement in the real-time transmission and monitoring, especially for weather system.

Medicolegal Sidebar: Telemedicine-New Opportunities and New Risks.

Medicolegal Sidebar: Telemedicine-New Opportunities and New Risks.

Multi-channel bioimpedance spectroscopy based on orthogonal baseband shifting

Objective. Multi-channel bioimpedance spectroscopy (BIS) systems typically sample each channel’s impedance sequentially using multiplexers and a single analog-to-digital converter. These systems may lose their real-time capability with an increasing number of channels, especially for low excitation frequencies. We propose a new method, called orthogonal baseband shifting (OBS), for high-speed parallel BIS data acquisition at multiple excitation frequencies with low hardware and computational effort. Approach. Similar to orthogonal frequency-division multiplexing, used for digital data transmission, OBS systems use channel-specific orthogonal carrier frequencies to modulate the voltage response of the tissue. Given a suitable choice of carrier frequencies, the modulated signals of all channels sum up without loss of information and cross-talk. The fast Fourier transform (FFT) of the summed signal reveals a spectrum of non-overlapping, interleaved BIS data from which the corresponding BIS data of each channel can be calculated. Main results. In simulations, the system design requires a minimum signal-to-noise ratio of 30 dB to achieve amplitude errors below 1% and phase errors below 0.8°. The hardware realization, called ‘AixBIS’, has been evaluated for impedance measurements between 0.1 and 10 Ω with multi-frequency excitations between 45 and 180 kHz. The impedance values acquired had an averaged precision of 3.67 mΩ, which is only 0.65‰ in relation to the measured impedance. The phase had a mean precision of 0.46°. Moreover, in vitro measurements achieved 140 full spectrum acquisitions per second. The impedance change measured in a silicone heart phantom showed a high correlation of 0.83 with the ventricles volume change (flow). Significance. The proposed method enables very fast impedance acquisition of all channels. A complete measurement is performed in the time of a single FFT acquisition, which is equal to the resolution bandwidth of the FFT. In addition, portable and low-power multi-channel BIS devices profit from highly reduced hardware effort. The outstanding performance of OBS measurements with the AixBIS system have the potential for in vivo BIS measurements in real-time.

BAYESIAN ESTIMATE OF TELECOMMUNICATION SYSTEMS PREPAREDNESS

The paper assumes a Bayesian estimate of the telecommunication systems availability ratio. Downtime and uptime are described by gamma distributions with positive integer parameters. Estimates of the distribution parameters are obtained using the maximum likelihood method. For the set samples, the values of the desired probability distribution densities are found and an expression for estimating the availability ratio is derived. Numerical estimates for the standard and assumed estimates are given. For a system with two states, a Bayesian estimate of the availability function with consideration of downtime and serviceable condition takes into account the features of backup equipment and the effect of its failure defined by performance reliability and features that ensure the reliability of information signals. The proposed Bayesian approach has the following advantages: it is possible to conduct quantitative estimates with lack of sufficient statistics on functional use indicators; it takes into account all destabilizing factors of various nature; the presence of a lower mean square error compared to traditional methods. To implement the proposed approach that estimates the availability ratio, confidence probabilities are introduced relative to the indicator of failure flows and equipment recovery. The parameters of the a priori information can be determined by different methods or on the basis of sufficient statistical data. To illustrate the discussed calculation algorithm, a digital data transmission system of a standard satellite navigation system consisting of terminal, radio equipment, and a transponder is considered. To estimate the required values, we used data on interruptions in the operation of equipment due to its malfunction during a conditional year. The frequency of downtime caused by signal propagation conditions and equipment failures was evaluated. It was shown that the gamma distribution is suitable for describing the frequency distribution of downtime. The frequency distribution of the cyclicity coefficient with the condition of the selected time interval was also taken into account. Sample mathematical expectations and mean square deviations of the downtime coefficient were found. As a result, the numerical example shows the correctness of using the Bayesian estimate of weighted equipment preparedness.

Interference immunity in channels with random phase and fading when using orthogonal coding and frequency modulation

In digital data transmission systems, it is proposed to use additional orthogonal coding along with error-correcting coding. The combined use of both types of coding can provide significant energy gains compared to using only error-correcting codes. Orthogonal coding is analogous to convolutional coding over the field of rational numbers, allows to provide the required transmission quality at lower energy costs. The energy gain in the signal-to-noise ratio, obtained through more efficient use of the energy of the transmitted signals, is achieved without increasing the complexity of the transmitting and receiving devices. Encoding and decoding devices that implement orthogonal encoding and decoding operations can be used to ensure information security in communication systems.

Enhanced AES algorithm based on 14 rounds in securing data and minimizing processing time

Computer, Internet technology have grown exponentially, and constant evolution until today. The usage of digital data such as text, images, audio, animation and videos are commonly used in many aspects of daily activity. The continuous increase in the use of digital data transmission over a network and it exposed to the various kinds of attacks, unauthorized access and network hacking. Thus, it is very hard to ensure that the digital data transmission are secure from any attacks and unauthorized access especially for sensitive and important digital data. This has been raised researcher’s concerns on security of the digital data. Digital data security has become one of the most important aspects in communication. Cryptography is one of the most important technology for protecting digital data. As there is need for secure communication, efficient and secure cryptographic processing is needed for desirable platform overall performance. Improvement of any communication platform with secure and complicated cryptographic algorithms incredibly relies on ideas of data safety that is essential within the current technological global. This paper propose a Secured Modified Advanced Encryption Standard Algorithm with decreasing the rounds of Advanced Encryption Standard (AES) to 14 rounds in order to minimize encryption and decryption process time and increasing digital data security as well. The results have been proved that the proposed technique provides higher efficiency in term of encryption and decryption process time compared to other researches while increase security which has been proved by using avalanche effect test.

Natural Amplification of Soft Defects Signatures in Cables Using Binary Time Domain Reflectometry

In our digital world, energy and data transmission play a major role and often rely on electrical wires. Some of these wires are used in harsh or aggressive environments and may be subject to defects. Security and preventive maintenance require tools to detect and precisely locate such defects. This paper details the Binary Time Domain Reflectometry (BTDR) method, presented earlier, which does not rely on the use of expensive and complex digital to analog and analog to digital conversion components. We explain the role of additive white noise and of the use of the time derivative for the improvement of its performances. The study focuses on BTDR's natural capacity of magnifying soft defects' peaks on the reflectogram. The method takes advantage of phase opposition to cancel the contribution of the extremities of the line under test and saturate the amplitudes of the remaining peaks. This can only be achieved if these contributions are equal or very close to each other. A balancing device is added at the cable's interface to meet this requirement. This low complexity additional system, made of two controlable digital potentiometers, is driven by the programmable logic digital system at the heart of the reflectometer. Direct magnification of very low amplitude peaks of incipient defects is obtained without any data post-processing. The amplification performance depends on the adjustment accuracy of the potentiometers and the hysteresis level of the comparator used to replace the converters.

Power-over-Fiber LPIT for Voltage and Current Measurements in the Medium Voltage Distribution Networks.

In this work, we present the design, laboratory tests, and the field trial results of a power-over-fiber (PoF) low power instrument transformer (LPIT) for voltage and current measurements in the medium voltage distribution networks. The new proposed design of this power-over-fiber LPIT aims to overcome the drawbacks presented by the previous technologies, such as the continuous operation (measuring and data transmission) for a wide current range conducted in the medium voltage transmission lines, damage due to lightning strikes, accuracy dependency on vibration, position and temperatures. The LPIT attends the accuracy criteria of IEC 61869-10 and IEC 61869-11 in terms of current and voltage accuracy and it attends the practical criteria adopted by Utilities companies including voltage measurements without removing the coating of the covered conductors. The PoF based LPIT was developed to be applied at 11.9 kV, 13.8 kV, and 23.0 kV phase-to-phase nominal voltages, and in two current ranges 1.25–30 A and 37.5–900 A. The digital data transmission of current, voltage, and temperature from the sensing unit to the processing unit uses a special synchronism technique and it is performed by two 62.5 µm multimode fibers in 850 nm. The optical powering in 976 nm is also performed by one 62.5 µm multimode fiber from the processing unit to the sensor unit. We presented all details of the sensor design and its laboratory characterization in terms of accuracy and temperature correction. We also presented the results of field tests of the sensor made in two different conditions: in a standard distribution network and an experimental hybrid fiber/power distribution network. We believe that these studies aim to incorporate optical fiber and devices, digital technologies, communications systems in electrical systems driving their evolution.

Estimation of hardware and time redundancy when using an additive error vector to correct burst errors in digital data transmission systems

In digital data transmission systems, to improve noise immunity, cyclic codes are widely used, detecting and correcting byte (packet) errors. An error packet is understood to mean errors whose multiplicity does not exceed the number of bits b of the information block. Cyclic codes are used to correct byte errors. The most effective method for correcting byte errors are Reed-Solomon codes, which allow correcting errors in a given number of bytes of information. The main problem of using cyclic (sequential) codes is a long delay time associated with the need to perform a division operation to obtain the remainder, which is not acceptable for digital data transmission systems operating in real time. For example, when using the Reed-Solomon code with a code set length of 69 information bits, the implementation of decoding according to the Euclidean algorithm requires 96 clock cycles, which cannot ensure the channel operation in real time. To eliminate this drawback, one should use codes that correct burst errors that implement an algebraic coding procedure with syndromic decoding of information. However, replacing the cyclic procedure for encoding (decoding) information with a syndromic one leads to a sharp increase in hardware costs associated with the use of a memory unit in the decoder for storing error vector values and a decoder for generating error addresses in accordance with the resulting syndrome. Thus, there is a need to develop a methodological apparatus associated with the construction of a code that corrects errors in a given number of bytes of information and an estimate of the hardware and time costs associated with this purpose. In this work, the need to develop a methodological apparatus associated with the construction of a code that corrects errors in a given number of bytes of information with algebraic syndromic decoding and an assessment of the hardware and time costs associated with this purpose is substantiated. The paper presents the rules for constructing a correcting code that corrects errors in a given number of bytes of information, which implements a linear procedure for constructing a correcting code with syndromic decoding and using an additive error vector, which made it possible to reduce hardware costs for constructing a decoding device (to reduce the amount of memory for storing error vector values). For the developed method for correcting byte errors, expressions for evaluating the number are obtained: checking discharges; additive error vectors that do not require their storage in a memory block; error vectors, for burst errors that occur in adjacent bytes at the same time and require their values to be stored in a memory block. A comparative assessment of hardware and time redundancy in the implementation of the proposed method for correcting packet errors with existing methods is carried out. The proposed method of error correction in a given number of bytes of information with additive formation of the error vector differs from the existing ones in that it allows: carry out the correction of burst errors with algebraic-syndromic decoding (exclude the cyclical procedure for encoding and decoding information); to reduce hardware costs for building a decoding device, since in most cases does not require hardware costs for storing error vectors; to reduce the time spent on encoding and decoding information and to ensure the operation of the data transmission channel in real time; to increase the reliability of the transmitted information by detecting uncorrectable byte errors. Thus, the proposed method for correcting errors in a given number of bytes of information with additive formation of an error vector has a regular and relatively simple procedure for constructing a code, which allows one to reduce the hardware and time costs for encoding and decoding information.

Fire development study on physical models of transport tunnels

The work gives the study results for 1:10 scale physical models of the road tunnels. The tunnel slope changes from 0 to 10% with a 2% spacing. As the models show, the fire strength varies within the range of 5 to15 MW with 5 MW increments. The properties of the tunnel geometry in nature are as follows: cross-sectional area: 46.7m2, length: 120 m, width: 8.5m, height: 5.5m and width and height ratio: 1.54. The models are made of 2 mm-thick stainless-steel sheets. We studied the nature of the spread of smoke, the variation of critical velocity depending on the tunnel slope and the characteristic value of such variation - the grade correction factor. The observation over such values is done depending on the air temperature variability in the tunnel model. The measurements are made with K-type thermocouples with open and closed detectors. Maximum temperature measurement is 800°C. The thermocouples are located in the holes provided in the ceiling of the tunnel model. The distance between the holes is 5 and 10 cm what corresponds to the natural length of the tunnel of 5 and 10 m. Fire is modeled by using the natural gas. The indications of thermocouples and air and gas meters are measured simultaneously and the primary analysis and the digital data transmission are provided with a Data Taker DT85 data logger. The gained results may be used to develop ventilation and emergency management projects for transport tunnels as well as to train personnel and rescuers.

Digital Media Art Communication Based on Wireless Cooperative Routing with Minimum Energy Consumption

Wireless cooperative routing algorithm transmits the data collected in the target area to users, so that users can obtain monitoring information timely and accurately. In the traditional low‐power adaptive clustering hierarchical routing protocol, the process of building clusters is random, the resources of nodes are not fully utilized, the node death speed is fast, the network life cycle is short, and the performance is not stable enough. In addition, the route maintenance process is cumbersome and will occupy a lot of bandwidth. In order to solve the problems of real‐time transmission of digital media art communication data and network lifetime optimization, a wireless cooperative routing algorithm based on minimum energy consumption is proposed. The facts of transmission strength consumption, node residual strength, and minimal information transmission extension are analyzed, a new weight feature is proposed, and a multipath statistics routing scheme is developed by using the usage of the minimal strength consumption. All digital media art propagation sensor nodes transmit data to sink nodes along multiple transmission paths. Simulation results show that the algorithm can prolong the network lifetime, reduce and balance the node energy consumption, reduce the data transmission delay, reduce the energy consumption of wireless cooperative routing based on the minimum energy consumption by 64.5%, and increase the number of compressed images by 182%.

Monitoring of moving objects in the absence of a GSM signal

Many modern transport processes require constant on-line monitoring and management. However, the main difficulty lies in the lack of a stable GSM connection. One of the possible solutions to this issue is the use of MESH networks. These represent the possibility of wireless communication between multiple entities, which are nodes on a distributed network. The article presents the results of the development of original local radio modules and a base station to ensure uninterrupted transmission of digital data from the monitoring object, in conditions of insufficient GSM coverage. The complex provides the following operating modes: simple interaction via a GSM channel, data transmission via a self-organizing network, as well as sensory interaction between objects. In the absence of GSM communication, the repeater provides on-line data transmission from the monitoring object, at a distance of up to 860 m, at a distance from the base station - at least 500 m. The use of the new complex makes it possible to promptly respond to changes in operating factors and prevent emergency situations during the operation of vehicles.

Error detection and correction implementation for computer networks using Arduino

Error detection and correction, in particular in high-data-rate and high-reliability wireless network applications, has received significant concentration. Error detection and correction are techniques that enable secure transmission of digital data through unreliable communications networks in the information and coding theory. The use of error detection and correction techniques leads to an increase in the performance of the network by reducing the end-to-end delay, reducing the bit error rate, and thus increasing the throughput. Since OSI and TCP/IP models have no bits corrections operation, and the only error detection operation is performed in the data link layer and the transport layer using Cyclic Redundancy Check (CRC). We suggest adding a sub-layer between the physical layer and the data link layer responsible for detecting and correcting errors in this paper. The hardware design of the proposed sub-layer using the Hamming code is implemented using Arduino. As a result, without having to demand retransmission from the sender, we will have a network device that can detect and correct a bit of error in the frames.

ОЦЕНКА ЭЛЕКТРОМАГНИТНОГО ФОНА ЭЛЕМЕНТОВ СИСТЕМЫ ПЕРЕДАЧИ ЦИФРОВЫХ ДАННЫХ ОТ МОБИЛЬНОГО ОБЪЕКТА

The article substantiates the possibility of harmful effects on humans and the environment of electromagnetic fields generated by modern wireless communication devices. The main results of work on the creation of a new system for uninterrupted transmission of digital data from a mobile object, in the absence of a GSM signal, are presented. The technique and measuring equipment used to assess the value of the energy flux density during the functioning of the developed receiv-ing-transmitting complex and the compliance of the EMR with permissible values are described. It has been established that the value of the flux density of electromagnetic radiation generated by the elements of the new radio transmission system does not go beyond the permissible values and is no more than 8.45 μW cm-2 - for a base transceiving station and no more than 5.02 μW cm-2 - for the radio module, at a distance of 10 cm from the object of radiation.

Improving Data Security using Compression Integrated Pixel Interchange Model with Efficient Encryption Technique

We exist in a digital era in which communication is largely based on the transfer of digital knowledge over data networks. Disclosures are sometimes regarded as a transmitter that transmits a digital file. A system of encoding, efficient and easy yet secure model must be developed for quick and prompt transmission. The file is sent from source to destination where it is difficult to maintain the privacy of knowledge. The encryption of images is vital for securing sensitive information or images from unauthorized readers. By using a technique of selective encryption, the original image pixel values are completely obscured in this way and an intruder cannot retrieve statistical data from its original image. This paper introduces a new methodology for the use of a protective facility for the transmission of digital data over the public network. A highly established field with image compression is allowed for speedy transmission and efficient information storage. During the initial process, the original image is divided into blocks of the same size and sub segmentation is performed for accurate extraction of images within the boundaries. A random matrix is used to swap the pixels of the neighboring sub blocks. Afterwards, each pixel is randomly exchanged for the neighboring blocks with a random matrix, then each block is encrypted with the proposed function and then the encrypted data can be stored in cloud. The proposed method uses Image Segmentation based Compression Model with Pixel Interchange Encryption (ISbCPIE) Model for providing high security to the Image transmitted in the network. Compressor is needed to achieve rapid transmission and efficient storage. The proposed model is compared with the traditional models and the results show that the proposed model security levels are better than the existing models.