R.N. Akinshin - D.Sc. (Eng.), Associate Professor, Leading Research Scientist, Section of Applied Problems of the Presidium of RAS
A.V. Khomyakov - Ph.D. (Eng.), First Deputy General Director, Chief Designer of Radio Systems, CDBAE. E-mail: rts@cdbae.ru
A.V. Novikov - Head of Section, CDBAE. E-mail: rts@cdbae.ru

The task to substantiate direction pattern and scattering pattern models and to estimate the character of model approximation to direction and scattering patterns of a real antenna was considered. It was suggested that approximation error parameters should be divided into two groups characterizing the direction and scattering pattern representation in the area of antenna beam and in the area of side lobes. As parameters there were used a differential error representing a differential feature for estimating direction and scattering patterns representation accuracy, and an integral conventional error used as a integral feature. The differential error is expressed in percentage terms and demonstrates the ratio of the area under the curve of the error of representing the sample pattern side lobes envelope to the area under the sample pattern side lobes envelope module. The integral conventional error is measured by decibels and demonstrates an average error of the sample pattern envelope representation. It was suggested that for estimating the accuracy of differential scatter features the following scattering patterns should be used: a monostatic scattering pattern; a bistatic scattering pattern by front illumination; a bistatic scattering pattern by side illumination. The total RCS was used for estimating errors of integral scatter feature calculation since the average total RCS and the total RCS are interconnected and in this case there is no need to average the findings.