Role and place of profit and cost split keeping in communication enterprises’ management
Added functionalities in new telecom technologies broaden the range of services, create new markets and increase the competition. The importance of timely acquisition of information about cost of services by the operator ensures the need for permanent improvement of accounting separation system. Key words: telecom, service, operator.
KREINDELIN V.B., PANKRATOV D.YU.
Joint application of antenna selection technologies and space-time coding
Systems with multiple antennas (MIMO systems) can significantly improve throughput and reliability of radio communication but require expensive apparatus and complex signal processing. Space-time coding (STC) technology is used for MIMO systems to improve signal-to-noise ratio (SNR). Antenna selection technology can reduce cost and complexity of MIMO systems (number of RF chains is less than number of antennas) and at the same time capture many of the advantages of MIMO systems. The combination of these technologies has been noted by several investigators, but much work remains in this area. In this article algorithms of joint application of antenna selection technology with STC technology are proposed. Key words: MIMO systems, STC, SNR, antenna.
GOLOVKIN I.V., NAZAROV L.E., NAZAROVA Z.T., MANIKIN D.N., SHEGLOV M.A.
Firmware realization of CCSDS convolution turbo-codes
The VHDL implementation of iterative decoding procedures with integer format for convolutional turbo-code CCSDS coding standard has been presented in the article. Key words: VHDL, CCSDS.
ANDRIANOV M.N., BUMAGIN A.V., KISILYOV I.G.
A system and method of interrupted communications in Nakagami fading channels
Algorithms of increase noise-immunity of digital communication when signal envelope fluctuation in Nakagami channel, using synthesis of interrupts communications and diversity reception are investigated. Gain of noise-immunity comparing this algorithm and usual method of diversity reception, and comparing this algorithm and single interrupt communications are estimated. Analytical expressions of probable error and coefficient of using radio line are defined. Key words: Nakagami channel, digital communication, algorithm, coefficient.
PETROV A.V., SERGIENKO A.B.
Joint blind estimation of frequency and phase offset for QAM signals using biharmonic approximation of likelihood function
The algorithm is presented for joint blind estimation of carrier phase and frequency offset for signals with quadrature amplitude modulation (QAM). The algorithm is based on a circular harmonic expansion of log-likelihood function (LLF). Retaining one or two most significant terms in this series gives a harmonic or biharmonic approximation of the LLF, this approach leads to notable improvement of the estimation quality comparing to known versions of popular 4th power frequency and phase estimation algorithm.
Computer simulation results are presented for two constellations: square 16-QAM and cross 32-QAM; they justify the advantages of the proposed method. It is also shown that the simplified implementation of the algorithm with fixed (independent of signal-to-noise ratio (SNR)) weighting functions leads to small loss only at low SNR.
Key words: blind estimation, frequency offset estimation, phase estimation, joint frequency and phase offset estimation, quadrature amplitude modulation.
Homogeneous computation environment dissection
In this article operating of abstract homogeneous computation environment is considered. There are two basic modes obtained by analysis of possible operating states. For this modes algerbraic expressions of operating effectiveness are derived and investigated. Keywords: algerbraic, abstract, basic mode.
MAMEDOV I.R., ALIEV Z.B.
Probabilistic description of a pilot-signal amplitude at the output of a feedback closed circuit
İn this paper the main probability characteristics of the Pilot-Signal Amplitude at the input of the Closed Feed-back Circuit Measurement of signal/interference ratio is determined. Is shown, that distribution of this amplitude is close to normal, when Pilot-Signal Amplitude fading is according to normal distribution or pilot-signal have been received by the moving object in the global region.
Key words: Pilot-Signal, Closed Feed-back Circuit, Signal-Interference Ratio, Normal distribution, Amplitude Fading, Global Region.
Digital radio broadcasting under 30 MHz. Illusions and reality. Part 2
The work analog and digital broadcasting systems on MW and LW bands in dark time of day are considered at presence of mutual interference. The comparative results systems operating are given in view of statistical properties of useful and interfering signals. Key words: MW, LW, interference, interfering signals.
GEVORGYAN D.A., NANASSIAN A.S., KHACHATRYAN K.O.
The independent SMS structures for enterprise applications
Paper discusses the application of widely used Short Message Service (SMS) for corporate needs. Emphasized are two types of SMS technology usage: SMS mass mailing system and Websms system. Some factors that limit the use of mass SMS services for business purposes are described, particularly, issues arising from the need to provide SMS service operator with the corporate information databases, which in some cases, unacceptable.
Problems associated with the use of mass SMS service for business purposes can be almost completely eliminated while using own corporate targeted SMS service, that send messages directly to the selected cellular networks. Such service systems can be effectively applied, particularly in organizations where it is necessary to provide just-in-time information to employees regardless of their location. The paper contains a list of functions corporate SMS service can provide.
Websms systems are presented in the paper as a corporate Websms-network, which operates as an independent communication system communicating with registered users only. The number of cellular networks, which it can operate with, is limited only by the mobile operators available in the region where the corporate users (department offices, branches, partners, communities, public bodies, etc.) are located. The system should interact directly with the selected cellular network, without any intermediaries, thus having its own independent means of access (gateways) to the given cellular networks. A list of functions for typical corporate Websms network is presented, including the function of targeted mass SMS service.
Most of the functions, discussed in the paper, are implemented in the corporate Websms system (www.websms.asnet.am) developed by the IIAP NAS RA. Key words: SMS technology, IIAP, cellular networks, communication system.
MASLOVA N.R., PEREKHDOV V.N., RODIN A.A.
Public examination of government services portal: Ugra’ experience
The article discusses the role of public comment in the formation of the electronic government systems for the improvement of the regional segment of the Unified Portal of State and Municipal Services and convenience of using these services by citizens and businesses.
At the regional level, the institute of public comment on the electronic government is still forming. Therefore, experience of the regions-leaders, such as Khanty-Mansiysk Autonomous Okrug – Ugra, has been particularly valuable.
Key words: information society, information and communication technologies, state and municipal services, electronic government, e-government.
DEART Yu.V., TZYM A.Yu., SHATOV A.Yu.
Reviewing investment market risks estimation methods
Information technologies as a factor of a municipal entity’s steady development
Modeling expenses and profitability estimates subject to a cellular communication company’s innovation development