SCIENTIFIC AND TECHNICAL JOURNAL «RADIO COMMUNICATION THEORY AND EQUIPMENT» ISSUE 2, 2008

**ADAPTIVE FREQUENCY HOPPING RADIO LINE**

*N.I. KOZLENKO, A.N. MOKROUSOV*

The algorithm that determines frequency hopping (FH) radio line adaptation to the jamming environment and information loss saving at reception is offered.

**COMPARATIVE EVALUATION OF CLASSICAL AND SEQUENTIONAL ANALYSIS EFFICIENCY OF SYNCHRONOUS FH RADIO COMMUNICATION SUPPRESSION**

*A.V. NEMCHILOV*

Methodology for comparative evaluation of frequency-based search efficiency, reasoning from the criterion of mean jamming time maximum and representation of correct frequency determination time as random variable is elaborated.

**REGULARITIES OF TRUNCATED SEQUENTIAL PROCEDURE FOR MULTIPLE HYPOTHESES PROOF BY LIKELIHOOD FUNCTION MAXIMUM**

*S.A. ZHITENEV, I.N. PLOTNIKOVA, T.V. FYODOROVA*

Sequential procedure for multiple hypotheses proof is examined. At each stage of these hypotheses, except the last one, decision is made, whether it is true or there is a need to follow-up examining. The solutions probability dependence upon procedure parameters evaluation was acquired by numerical methods. On its base the optimum values (according to the criterion of «minimum average number of stages with limitation imposed on error tolerance probability») of those latter and simple formulae for evaluating potentially available procedure quality index in function of data comprehension, the number of hypotheses and error tolerance probability are established.

**EVALUATION OF FREQUENCY HOP MOMENT FOR FH-SIGNAL IN RADIO RECONNAISSANCE**

*V.I. BORISOV, V.Ì. ZINCHUK, A.E. LIMAREV, A.V. NEMCHILOV*

In order to evaluate a frequency hop moment for creating synchronous suppression mode, it is offered to apply a theory of random properties behaviour detection. Two approaches to evaluate frequency hop moment are discussed: the first one is on the base of fixed volume sampling, the second one is on the base of cumulative sum algorithm designated for sequential procedure. Modeling and numerical calculation results are given.

**FUTURE GENERAL-PURPOSE AND PROFESSIONAL COMMUNICATION-SYSTEM ANTENNA DEVICES**

*YU.B. NECHAEV, V.I. NIKOLAYEV, A.S. RYAKHOVSKY*

The ways to increase directivity for antennae deployed in base and subscriber stations are offered. The ways to narrow the antenna pattern in Å- and Í-planes of small-sized radiating structures on the base of slotted resonant and microstrip radiating antennae are described. Antenna characteristics were determined by using simulation techniques basing on mathematical models elaborated.

**THEORETICAL- INFORMATIONAL APPROACH TO EXPERT COMMUNICATION MEANS AND SYSTEMS QUALITY EVALUATION**

*S.A. BABKIN, S.V. BUKHARIN*

A methodology of selecting an expert group for evaluating communication system component quality basing on generalized dispersion and information theory is proposed.

**METHODS OF RADIO-RECONNAISSANCE RECEIVER PROTECTION AGAINST INTERMODULATION INTERFERENCE**

*A.V. NEMCHILOV, A.À. BADERKO, A.N. SAMOILOV*

Realization of traditional technical ways of intermodulation interference avoidance maximal or restriction in reconnaissance receivers is connected with great technical difficulties. Tasks of elaborating new ways of equipment protection against intermodulation interference based on their algorithmic selection in the course of secondary processing in the group signal processor are given.

**CHARACTERISTICS OF ANTENNA SYSTEM ELECTROMAGNETIC FIELD ON THE RANDOM PROFILE CYLINDER**

*D.D. GABRIELYAN, Ì.À. DONCHENKO, Î.V. KALCHENKO*

The solution for the problem concerned with ideally conducting random profile cylinder excitation with infinite generatrix system of longitudinal electrical dipoles is discussed. It is offered to carry out an integral equation solution applying a pseudoinverse matrix.

**ESTIMATION METHODOLOGY FOR FREQUENCY-SYNTHESIZER NOISE CHARACTERISTICS**

*S.K. ROMANOV, A.I. MATYTSINA, N.M. TIKHOMIROV*

Using MATHLAB system, correlations for calculating noise spectrum at frequency synthesizer output are received. Its structure includes fractional frequency dividers, delta-sigma modulators, pulse-phase detectors with non-identical pumping currents and active low-pass filters.

**ADAPTIVE LINEAR SUMMING DEVICE ALGORITHM EFFICIENCY**

*A.V. RYZHKOV, À.À. TEMNYSHOV*

Effiency evaluation for adaptive linear device that is used for strong interference rejection with unknown direction of useful signal arrival is carried out.

**GENERALIZED ANALYSIS OF NON-LINEAR DISTORTIONS IN AMPLIFIERS WITH NON-LINEAR CORRECTION**

*O.F. BOKK, E.N. RODIONOV*

Methodology for fine non-linear distortions in amplifiers is developed, including multicascade amplifiers with feedback. Generalized mathematical description of non-linear signal transformation at amplification stages with direct non-linear correction and non-linear feedback is received. Estimation of non-linear distortions in bipolar transistor amplifiers is carried out an experimental validation of received results is conducted.

**HIGH-EFFICIENCY POWER AMPLIFIER FOR RADIO TRANSMITTING DEVICES WITH LOW-LEVEL UNDESIRED RADIATION**

*YU.V. ZAVRAZHNOV, N.À. TRUKHIN*

Power amplifier construction by method of linear amplification of high efficient non-linear elements with low noise, mutually modulated, intermodulated and harmonic oscillations is examined. Experimental test results for 10 kW amplifier built by this method are given.