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The most efficient transmission system of the transport network is OTN offered by ITU-T G.709. However, in this recommendation, there is no indication as to what degree of MQAM determining the number of points of signal constellation provides the maximum capacity of multichannel system. This work removes this gap.
High permittivity with small dielectric losses in frequency range of 1…100 GHz can be realized only due to quick-response mechanisms of polarization. In the report some new assumptions as to thermal stability realization is proposed. Firstly, microwave dielectrics should be based on “hard” paraelectrics, which structure resists to polar phases formation. Secondly, high thermal stability is caused...
The results of the development of a modern domestic compact troposcatter radio relay station, both general and special purpose (dual purpose) are presented. The station is characterized by low power consumption, compact dimensions and low weight due to the use of the newest element base of microelectronics in extremely high frequency range, modern radio technologies for the formation and transmission...
The importance of the task of countering the means of unauthorized access is to preserve the integrity of restricted access information circulating in computer networks determines the relevance of investigating perspective methods of cryptographic transformations, which are characterized by high speed and reliability of encryption. The methods of information security in the telecommunication system...
In this paper the influence of momentum relaxation time on electron drift mobility in ternary alloys in case of potential alloy scattering is examined. It is necessary for simulating the dynamic properties of devices and appliances based on solid solutions of binary semiconductor compounds. Momentum relaxation time is obtained in the adopted method by averaging electron scattering rate by its distribution...
As was declared in our previous research published during 2006–2014, related mostly to terrestrial communication links, sub-urban and urban, and lesser — to land-atmospheric communication, the most important issue is to understand processes which distort information due to fast fading, as the source of the multiplicative noise, passing within the wireless communication links. The same processes occur...
In this work, destabilizing factors affecting the quality and resolution of images, multispectral monitoring systems in the optical (visible and infrared) and microwave bands are analyzed and systematized. The analysis of the influence of destabilizing factors on the formation of images in multispectral monitoring systems allows us to take into account the described effects when creating of domestic...
The possibility of using photon counters based on avalanche photodiodes to implement a quantum system for key distribution is shown. The security of encryption key distribution is realized with application of eavesdropper detection technique. The detection technique uses quantum control signal. The structural scheme of the quantum system is presented. The effect of photodetector parameters and the...
The paper presents the results of modeling adaptive decomposition for ultra-high definition television, which provides image compression without subjective deterioration of quality. The decomposition of the images was carried out in the spectral region for the cases of wavelet analysis and Fourier transformation, depending on the signal-to-noise ratio at the image edges. Quantitative estimates of...
Today the continent of Antarctica is the only uninhabited and undeveloped continent on Earth. Currently meteorological, oceanographic and geological scientific reseaches are conducted on the continent supporting by state target programs of many countries, including Ukraine. Therefore, the need of communication in the Antarctic is growing fast with the high rates of scientific activities on the continent...
The main negative factors that are inherent to modern society are presented. A hypothesis has been put forward. It supposes that a number of fundamental factors must be added to the basis of modern economics. Here are five factors that determine the paradigm of sustainable development of society.
The document contains a comparative analysis of the key technologies to ensure collaboration of telecommunication networks that were built with using different versions of IP protocol: dual stack; tunneling and encapsulation; translation of the protocols. Two groups of factors are proposed: factors that will influence the choice of the technical migration way to the IPv6 stack and the factors that...
The article examines effective organizational and technical countermeasures to hybrid threats, national cyber defense systems in developed countries. It is suggested a list of sufficient components for effective design and development national cyber defense system of Ukraine.
The paper presents the structure and peculiarities of the developed database used for Kharkiv incoherent scatter radar data storing. The heterogeneity of the raw data, the existence of specific periods of data acquisition, the use of the IS radar data processing program to estimate size and quality of the data, the use of the external server to store the results of data processing, and the ability...
A method of optimizing the use of server resources that can reduce the energy costs of a network while preserving service quality parameters is proposed in this paper. This method involves the use of resource involvement schedule based on long-term statistics. Unlike existing methods, proposed method simultaneously considers the losses of requests, expected delay and energy efficiency of processing...
Investigation results of signal formation peculiarities are presented for the autodyne short-range radar system using the symmetric saw-tooth law of frequency modulation. Experimental data is obtained with the Gunn-diode 8mm-range oscillator with frequency tuning with the varicap help.
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