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A mathematical model of the data display system for a simulator with distributed processing has been developed. The open-loop single-channel lossless mass service system (MSS) and MSS scheme with the absolute service priorities have been selected as the model basis. The assessment of the efficiency indices and latency by different queuing system service disciplines has been carried out.
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Determining the influence of the underlying surface on the propagation of an electromagnetic wave of the UHF and SHF bands plays a crucial role in the design of the radio communications, radar, television and mobile stations. In the work a new method for determining the influence of the earth surface has been considered taking into account the reflection from the earth surface, scattering and absorption of radio waves in the earth atmosphere. The reflection coefficient, the propagation factor of the radio wave, the potential of the radio communication and location station have been calculated. It has been shown that to ensure the smallest influence of the reflecting surface on the propagation distance of radio waves, it is necessary to arrange the parts of the radio communication (location) system at the Brewster angle, since the modulus of the reflection coefficient of the electromagnetic wave from the surface is minimal. It has been determined that the strong irregularity of the underlying surface also minimizes its effect on the potential characteristics of the devices being developed. It has been explained that this is due to the defocusing of the reflected electromagnetic wave and a decrease in its amplitude at the receiving end of the system. The results obtained are of interest for optimization of the parameters of the developed radio communication and location systems, as well as during the laying of the radio communication route.
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At present, the method of multi-view detection of targets becomes apparent only for targets, which approach or recede from the radiolocation station and do not change their azimuth position. In these methods the target detection is executed in the distance-survey number plane. As a rule, the real targets may have the complicated trajectories of movement, for example, unmanned aerial vehicles. Therefore, it is necessary to develop a method taking into account these trajectories. In the work a modified method of the target detection using the Hough transform on the coordinate x - coordinate plane has been proposed. In this case, the target, which moves between the azimuth directions, would be detected. To determine the efficiency of the target detection using the developed method the simulation of the target detection in the MATLAB medium has been carried out. It has been determined that the probability of detecting the uniformly moving target can be 1.6 times increased.
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The main world automated control systems of the traffic regulations have been considered. The analysis of the components of such control systems based on it has been performed and the main disadvantages have been revealed. It has been proposed for creating the automatic system of the traffic regulation control to use the radio frequency identification (RFID). The description of the developed induction system of detection and identification of vehicles based on RFID has been presented.
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The electronic system using the RFID-technology for automation of the traffic situation control has been proposed. For this electronic system the mathematical model for magnetic field in the near-field region has been developed and the results of the model analysis have been presented.
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Unsanctioned intrusion of unmanned aerial vehicle (UAV) on the territory of the guarded object is primarily detected by specialized radio surveillance systems. The results obtained by radio surveillance systems are used for aiming of UAV visual identification and radio jamming systems. In this work, the problems of UAV detection and tracking of the target trajectory are considered. The known tracking filter systems for radio surveillance application were analyzed and a specialized matrix tracking filter system was proposed, which uses in its algorithm a dynamically changing energy potential of the radio surveillance system. The developed tracking filter system efficiency is evaluated using methods of matrix calculation, mathematical modeling, and probability theory. It has been established that the developed tracking filter system lets the radio surveillance equipment most effectively initiate trajectories of UAV, set its movement window, consider radio surveillance equipment characteristics, and approximate the trajectory of UAV at times of missed detections connected to radar cross-section fluctuations of moving targets. A high efficiency of the developed system has been achieved by decreasing the inaccuracy of the target position prediction two times in comparison with the known tracking filter systems. The obtained results allow easy scaling of the developed tracking filter system for its application as a part of any radio surveillance system.
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The problem of the motion compensation in digital dynamic video images is urgent. The motion compensation for the purpose to improve the compression ratio of video information and to ensure the energy efficiency of television systems as a whole is being carried out. The existing approaches to solving the motion compensation problem have been described. The method of the motion compensation prediction on the basis of the mathematical apparatus of vector fields, which has made it possible to accelerate the process of movement compensation due to identifying the area of the image, the fragments of which have similar speed characteristics, has been proposed. The results of the given method simulation have been presented. The developed method allows an almost twice reduction of the computer time for the motion compensation in video images with the same indices of code volume and the quality of the images being decoded.
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The comparative analysis results of the ways to compensate movement of the frame sequences in television images have been presented.
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