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The present paper describes the implementation of a microstepping control of a stepper motor with advanced mixed current decay mode. The proposed development is based on a programmable field array (FPGA) and a galvanically separated ADC, which allows for continuous measurement and filtering of current through the windings of the motor used. It makes a comparison of the maximum reached frequencies of the control pulses supplied to the motor windings for the proposed algorithm with advanced mixed current decay mode and microstepping control without current decay mode.

A study of an LLC resonant DC/DC converter with capacitive output filter is accomplished. On the basis of an existing unified analysis based on the “first harmonic approximation” method, expressions for the determination of currents through the power devices and the resonant circuit components are obtained. The main load characteristics of the converter at ZVS mode are built.

The paper presents design consideration for the LLC resonant DC/DC converter with a capacitive output filter. Different conditions for receiving ZVS commutation are discussed, as well as the possibility of using ZVS drivers, allowing operation with soft switching within wide load range. The design procedure was verified through simulation and experimental results.

A unified analysis of the LLC resonant DC/DC converter with a capacitive output filter is proposed. For this purpose, the “first harmonic approximation” method is applied. Expressions for determining the main quantities of the converter are obtained. Dependencies for receiving the main converter quantities are determined. The switching areas of the transistors at zero voltage and zero current commutation are obtained.

In this paper, we have analyzed Daugman's integrodifferential operator which is used for iris localization. The several problems meeting at operator's implementation stage are considered in detail. One of these problems is selecting a step size for the numerical integration. We have presented examples of cases when using large step size leads to localization error. The detailed analysis of such examples is provided. The issues with a computational efficiency appear when using too short step. To increase the efficiency, we have proposed the method based on Bresenham's algorithm for computation of operator's integral part. Adaptation of Bresenham's algorithm allowing to compute operator in separate arcs has been proposed. The algorithm uses only integer-based arithmetic which improves the speed and accuracy. A high speed of the proposed method in comparisons with the conventional one has been confirmed.

Brushless machines are used in a number of light electric vehicles. As these vehicles have autonomous battery power, a regenerative braking mode is used to increase their mileage. The following paper investigates and analyses methods for converting a three-phase voltage inverter into a bidirectional voltage converter for the regenerative braking of an electric transport vehicle. A mathematical analysis of the conversion processes has been proposed for each algorithm and the experiment results will be presented.

The paper presents the mathematical model for SDN operation that describes counter values as a network flow function in the rule dependency graph. The basic properties of this model are explored and it is demonstrated that this model can be used to create an algorithm for counter values prediction. SDN provides a mechanism for network statistics analysis through counters that measure the number of packets processed by each forwarding rule. One problem with this mechanism is that in order to get complete network statistics, SDN controller has to send a lot of counter requests thus imposing a large overhead on the control channel and network devices. Thus, in order to minimize network load due to such requests, we need an algorithm that can predict counter values for each forwarding rule based on the minimum number of chosen counters.

G-TCP represents novel transport protocol designed to be used by Next Generation Networks. It engages famous Fibonacci sequence to calculate congestion window size when the protocol operates in congestion avoidance phase. Modification of window decrease parameter is introduced in order to improve protocol behaviour in high and low speed networks.

Development of the Next Generation Networks is ongoing process. The research community is focused on development of 5G network that will assure advanced communication. Solutions are argued on daily basis and are expected to be finalized around 2020. In this paper, we present an advanced transport protocol, designed to assure efficient data usage in the future 5G mobile networks. This transport protocol is created to prevent congestion collapses of the backhaul traffic and to assure ultra-high data rates up to 400Gbps.

Development of Next Generation and Future Networks is continuous, ongoing process. These days number of researchers are focused on development of 5G network that will provide improved future communication. Fundamental design, requests and drivers are defined and argued on daily basis expected to be finalized around 2020. In this paper we discuss future 5G network design and present novel transport protocol, designed to assure efficient data usage in future 5G mobile networks. This unique transport protocol is designed to prevent congestion collapses of the backhaul network traffic and to assure ultra-high data rates up to 400Gbps.

The century of technologies opened a new chapter of opportunities for improving the quality of life and security of the people. The ability to measure and convert analog information into digital data based on electronic and micro-electromechanical sensors is used for many different applications. But given various standards for interfacing, different hubs need to be built to support every one of them, which is not practical. On the other hand, a single hub that supports all is impossible due to complications of everyday situations. The goal of this project was to develop a configurable sensor node for sensor networking and universal measurements, where a single hub can support different types of low-level communication standards. Case studies on actual implementation verify the applicability of the system for the smart home.

Internet has developed into dynamic network where users use wired/wireless access technologies. The diversity of bandwidths, delays and error rates observed on Internet have increased. TCP is the common denominator for many services therefore by modifying TCP the need of applying solutions locally can be reduced. We focus on making TCP more efficient in a way to speed up its slow start phase, phase that tries to find good congestion window size. Different Slow Start algorithms will be analyzed and new variant will be proposed.

Synergy of Internet, wired and wireless networks is done. TCP remains the most important and most used transport protocol for non real time services such as web, email, ftp, which are basis for additional value-added or novel IP-based services. In this paper we conduct detailed analysis of the impact of the Duplicated ACK and Delayed ACK parameters on the throughput in multihop wireless scenario with incorporated loss models under traffic load provided by different TCP versions.

The need for evolution, change and constant communication are the forces that drive the advancement of the modern telecommunications. All IP networks with centralized management are reality. TCP is the most important and most used protocol in the todays wired and wireless communication. If we want to improve the throughput of the network then we have to improve the transport protocol, to optimize it and predetermine its behaviour in variety of environments. In this paper we conduct detailed analysis of the impact of the Duplicated ACK parameter on different performance parameters such as throughput, congestion window, slow start threshold, in bottleneck scenario with incorporated loss models under network load with different versions of TCP traffic.

Today's Internet connectivity is based TCP/IP protocol suite, which was designed for wired and static hosts. Wireless access links and mobility of the wireless users influence the behavior of Internet major transport protocols. Performance of the Internet transport protocols may significantly degrade when end to end connection includes wireless links where packets delays and losses are caused by mobility handoffs and transmission errors. In this paper we show performances analysis of the Internet transport protocols in wireless environment.