SCIENTIFIC AND TECHNICAL JOURNAL «RADIO COMMUNICATION THEORY AND EQUIPMENT» ISSUE 2, 2006

**SEQUENTIAL ALGORITHM FOR DETERMINING THE FH SIGNAL FREQUENCY HOP. PART 1. OPTIMALITY CRITERION AND SOLUTION METHOD**

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

To determine the FH signal frequency hop, a sequential Bayesian procedure with optimum stopping rule that provides maximum time for covering this element with repeater jamming is offered. Various types of processing are discussed, comparison of a sequential procedure and procedure based on fixed volume sample is carried out.

**TWO-STAGE ALGORITHM FOR MULTI-CHOICE SIGNAL DETECTION AND IDENTIFICATION WITH EXPERIMENT PLANNING SYNTHESIS AND ANALYSIS**

*V.M. ZINCHUK, YU.N. MAKSYUTA*

The problem of optimum two-stage algorithm for sequential multi-choice detection and/or signal identification with planned monitoring time at the second stage is discussed. General solution of the synthesis problems for the case with unknown detectable signal occurrence probability is presented.

**APPROXIMATION FOR PROPER SOLUTION PROBABILITY IN CHECKING MULTIPLE HYPOTHESES FOR RADIO ENGINEERING PROBLEMS**

*S.A. ZMAEVA, I.N. PLOTNIKOVA, P.V. POVETKO, T.V. FYODOROVA*

Quantitative assessment and analysis of errors in approximation formula for proper solution probabilities in hypotheses checking is carried out.

**EFFICIENCY OF RADIATION SOURCE DIRECTION FINDING USING NON-PROPERLY STRUCTURAL RESOLUTION METHODS IN RADIO DIRECTION FINDERS WITH FLAT ANTENNA ARRAYS**

*YU.B. NECHAEV, S.A. ZOTOV, E.S. MAKAROV*

Analysis of radiation source direction finding efficiency is carried out by means of super-resolution methods taking into account flat antenna arrays geometries. Direction finding characteristics in function of antenna array types, the number of elements and signal-to-noise ratio are found. The assessment of direction finding algorithm tolerance to reception channel amplitude-phase error is carried out. Monitoring time effect upon direction finding precision is evaluated.

**SIGNAL SEPARATION ALGORITHM FOR MULTI-USER COMMUNICATIONS SYSTEMS**

*V.S. RODIONOV, A. YU. SAVINKOV*

An algorithm allowing doubling the number of some kind signals separated by the antenna array without increasing the number of antenna array elements is offered. The algorithm tolerance to increase of users number and to high-rate fading is investigated.

**NON-LINEAR DISTORTION ANALYTIC FORMULAE IN AMPLIFICATION CASCADES WITH INVERSE FEEDBACK**

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

Mathematical description for non-linear signal transformation in amplification cascades with inverse feedback without restricting the active element non-linearity view is found. Analytical formulae determining the active element non-linearity are given. Analytical formulae determining non-linear distortions in complex amplifying devices having several elements inclusive in the feedback circuit are presented. A principle of sequential building-up for multi-cascade devices is formulated.

**EFFICIENCY COMPARATIVE ANALYSIS OF TWO ALGORITHMS FOR INDEPENDENT LAND MOBILE OBJECT TWO-DIMENSIONAL COORDINATE DIRECTION FINDING CALCULATION ACCORDING TO THE DATA
ON THEIR VELOCITY PROJECTION**

*V.I. SUCHILIN, G.B. VOLOBUEV*

Using computer simulation methods, an efficiency comparative analysis of two algorithms for independent land mobile object two-dimensional coordinate direction finding calculation in accordance with the data on their velocity projection is carried out. One of the algorithms is based on applying Kalman filtration, the other one is based on «one point» heuristic rough calculation. The root-mean-square error (RMSE) of coordinate calculation was selected to be an efficiency criterion. RMSE gain – data precision dependencies of one algorithm versus the other one are calculated.

**DETERMINING THE POTENTIAL HAZARD OF UNITARY CODE FLOW DURING INTERACTION AMONG INFORMATION AND COMMUNICATION COMPLEX ELEMENTS**

*V.I. NIKOLAYEV, N.N. TOLSTYKH*

Basing on the analysis of random walk potential kernel change taking place while processing the unitary code that circulates over the information and communication system, an algorithm for assessing the potential hazard of such code random sequences stored, processed and transmitted by information and communication system elements is defined.

**ADAPTIVE, SITUATIONAL AND REFLECTIVE CONTROL OF AUTOMATED TELECOMMUNICATION COMPLEX INFORMATION SECURITY**

*V.I. NIKOLAYEV, N.N. TOLSTYKH*

Formalized simulated representation of the automated telecommunication complex information security subsystem control process in the mode of information collision with using adaptive, situational and reflective control methods is discussed.

**ELECTRODYNAMICS MODELS AND ANTENNA DESIGN BASED ON DIRECTIONAL STRUCTURES WITH RADIATION**

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

The ways to increase communication system base station antenna device directivity are discussed. A technique of narrowing the antenna pattern in vertical plane is offered. The antenna device directivity characteristics are determined by means of simulation modeling based on boundary-value problem solution for electromagnetic field strength complex vector. Cylindrical slot antenna mathematical model at the electro dynamic level of rigor is designed.

**INFORMATION MESSAGE SECURITY AND ANTI-JAMMING ENHANCEMENT BY MEANS OF USING PSEUDORANDOM SEQUENCES AND FREQUENCY HOPPING**

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

Assessment of efficiency rational relationship between the offered initial information transmission method and already existing ones that use pseudorandom sequences and frequency hopping is given.

**DATA COLLECTION, PROCESSING AND TRANSMISSION MODELS IN MULTILEVEL INFORMATION CONTROL SYSTEMS**

*P.V. POVETKO, E.G. SUKHOVEY, YU.S. SUKHORUKOV*

The principles for transforming the distribution process duration probability laws according to the system levels and their effect on data used by control subsystem relevance probability are analyzed. Analytical expressions for assessing the time-probability characteristics of data collection, processing and transmission model in the multilevel information control system and data relevance probability are proved.

**NORMALIZING WIDE-BAND RECEIVER INTERFERENCE IMMUNITY AGAINST NARROW-BAND INTERFERENCE**

*A.P. ZHUKOV, A.V. LOMONOSOV, S.A. MACHNEVA*

Minimal set of technical characteristics and parameters that allows carrying out calculations for estimating the interference immunity and normalizing the wide-band signals in the radio communication system receiver against the impact of single narrow-band stationary interference is defined.

**COMPARISON OF SOME MODERN COMMUNICATIONS SYSTEMS**

*YU.I. LEBEDEV, S.A. POSTINIKOV*

Presently the practice of creating communications networks on base of «Wi-Fi» and «WiMAX» technologies is being much advertised and widespread. The object of the present work is comparative analysis of such system design principles, designing charges as well as their comparison with original domestic developments taking as an example a system designed by JSC “Concern”Sozvezdie”.

**CONVERGENCE OF IMPROPER INTEGRALS OF PROBABILITY INTEGRAL WITH POWER AND EXPONENTIAL FUNCTION PRODUCT**

*N.E. KOROTKOV*

Theoretically widest conditions (necessary and sufficient) for improper integrals of probability integral with power and exponential function product convergence with their linear and quadratic indices are derived for arbitrary shape integration contours on the complex surface. Some particular types of these conditions with reference to real infinite limits of integration inclusive the similar integrals in the present branch are described.