Исследование передачи Web-данных в сотовых сетях
Provides an overview of the principles of organization of communication in decentralized wireless networks is reviewed. The scheme of the decentralized network and the timing diagram of data transfer between nodes are shown. Investigated the problem of ensuring the effectiveness of collaboration with a number of nodes in low-power networks and consider the possibility of using for this purpose a probabilistic network Protocol data-link layer. The analysis of the algorithm access to the environment in a decentralized network, presents its block diagram. Detail displayed blocks of the algorithm that determine when data transmission from the network node. Through computational experiments on a model of a decentralized network investigated of the dependence of the efficiency of the work of the algorithm access to the airwaves from such temporal characteristics as the delay before sending data and waiting period before attempting to send them. The most loaded time point identified in the network exchange. It is shown that the developed computer program allow to calculate the probable collisions in the air. Suggested hardware implementation of the algorithm based on microcontroller STM32F030F4P6 of ST Microelectronics and transceiver CC1101 of Texas Instruments.
The paper is conducted the research and development of methods of interaction and methods of detection of mobile devices on the wireless networks of LTE using D2D (device-to-device) of interaction, and methods of routing of a traffic is conducted
Wireless body area networks standard (WBAN, IEEE 802.15.6) is currently an active area of research. In this paper, we present the criteria for the selection of a modeling system which is most suitable for the WBAN research. The structural model of the WBAN node is given. We reviewed and compared existing open-source modeling systems, such as NS-2, NS-3, OMNeT++Castalia, OMNeT++MiXiM, TOSSIM. As a result Castalia network simulator was chosen for WBAN modeling.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.