Radar systems are designed to detect targets in the air, at sea or on land. Radar cross section is the most important parameter that affects the radar detection of the individual targets. It is a part of radar equation, which in general and simple manner describes the principle of radar detection. By analyzing the radar cross section it has been demonstrated the importance of this parameter in radar detection. In this thesis, the radar detection principle and radar cross section definition are described in aspect of target detection with individual radar systems. The main part of this paper includes the analysis and description of various methods for reducing the radar cross section. These specific methods have been developed primarily for military needs. One specific method is surface shaping where you can by creating adequate shapes of individual objects redirect incident electromagnetic waves away from radar receivers and thereby achieve the desired invisibility. The surface shaping has been analyzed in details. Surface shaping is the most important method for reducing radar cross section. Mathematical calculations show the effect of surface shaping to radar cross section values for simple objects. The impact of surface shaping has been analyzed on specific models of basic shapes using analytical calculations in MatLab and simulations in COMSOL simulator for different two-dimensional shapes. An important way of reducing radar cross section is also the use of special radar absorbing materials. The characteristics and features of these materials have been analyzed. Their effectiveness have been confirmed with help of simulations. The simulation results were also compared and validated with analytical calculations. All methods of reducing radar cross section can be joined in a common technology called stealth technology. The development of this technology is primary intended for military defense and it is based on hiding against the enemy or from radar systems. On the other hand there have been also developed some successful methods and technologies that can effectively resist the stealth technology.
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