Dependence between permissible depth of visible physical objects and necessary geometric sizes of stereoimages is established. Expediency utilization of one projector is proved.

Now satellite communication systems with zone service start to be used. For the optimum frequency-spatial planning of such systems it is necessary to know their power characteristics and satellite repeater multibeam antenna pattern. It is also needed to define a method which will allow constructing the optimum frequency-spatial plan for various operating conditions of the system. The operation of satellite communication system with zone service is analyzed in this article. Also digital multibeam antenna array parameters are defined. The coordination rings method is offered as an optimal frequency-spatial planning technique.

The problem of improving effectiveness of electromagnetic metal detectors is considered. A solution is based on introduction of adaptive compensators in their structure.

When frequency territorial planning of land tele-radio broadcasting networks, building new operating transmitting stations or while reconstructing them, there is a problem of their site optimization and technical characteristics definition. When defining station site optimization, it is necessary to make a calculation of signals fields' strength and interference taking into account the intervals profiles constructed in the direction from the station site to the broadcasting border area. In the article, the decision of optimization problem of RTTS site by means of calculation of service areas and zones of shades of broadcasting transmitters with the use of the automated system of calculations and geographical information system is made.

Results of investigations of а pulse-width system (PWS) with negative feedback are presented. Based on an asymptotic method of linear system's order reduction, we suggest a technique of reducing the PWS to an equivalent nonlinear amplitude-pulse system for which known methods may be applied. A possibility of PWS analysis is considered for the cases where the response of the linear part of PWS to pulse inputs is known or can be calculated.

Efficiency of using parallel programming methods for analysis of high dimensional closed queueing networks is considered at this article. Parallel algorithm for evaluation of normalizing constant of closed homogeneous queueing network is described. It is based on decomposition of closed queueing network state space. Acceleration of parallel algorithm in comparison with serial one is evaluated.

The task is estimating the white noise influence on the quality of receiving messages in invariant communication systems. The formulae for calculating the conditional densities of probable values of information elements on the output of a demodulator are gotten. The special properties of the conditional density probability are defined, which are necessary to be considered when the practical realization of invariant communication systems occurs.

An engineering method to define the distance of atmospheric link with necessary readiness factor is described. The results are based on statistics of meteorological visibility range for Novo-sibirsk. Technical characteristics of Free Space Optic (FSO) systems are considered and a table of recommended distance of atmospheric link with necessary readiness factor for Novosibirsk is provided. The results can be useful for communication operators of Novosibirsk.