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Radar cross sections of such objects as metal thin cylinder, folded plate and straight edge, vary closely to (sinx/x)2 law in the vicinity of the principal maximum of backward and bistatic scattering patterns in directions of ray reflection, or shadow or diffraction ray path. It is shown that the effect can be explained on the basis of Fresnel zone concept. Scattered field in the vicinity of principal maximum is presented as a superposition of contributions of two object's ends. Each contribution is a half of the field of the first Fresnel zone, counting from the object's end. It results in independence of the scattering pattern envelope from the object's length in the vicinity of principal maximum. Transition to independence of radar cross section ceiling value from the object's length occurs, when one or more Fresnel zones are located along the object.

The results of the research and development of the unified radiotechnical characteristic of aircraft radomes are presented: an increase in the level of antenna side radiation, associated with the presence of a radome in front of the antenna. It is shown that for an objective assessment of the radio engineering quality of radomes the integral characteristic is best suited – the average increase in the level of antenna radiation power in the required sectors of viewing angles. It has been demonstrated that this characteristic weakly depends on the properties of the antenna with which the radome is estimated.

The problem of interpreting and changing the meaning of terms is relevant in many sciences, including in linguistics. The authors touch on the problem of different interpretations of basic terms in the landscape studies. The article deals with the history of the origin of the terminological vocabulary of the landscape science, describes the problems associated with its use by specialists and the changing meanings of terms over the past decades. Whereas these terms are mostly used interchangeably, there are obviously some fine differences in meaning. In this paper, important moments of the scientific understanding of the basic terms of landscape are presented.