Yu. I. Belov - Ph.D. (Phys.-Math.), Head of Laboratory of Physics Research Institute. E-mail: belov@nirfi.sci-nnov.ru Ye. L. Varentsov - Head of Research Team, FSUE FRPC - Measuring System Research Institute n.a. Yu.Ye. Sedakov - (Nizhny Novgorod). E-mail: elvarentsov@mail.ru M. I. Dudkin - Research Engineer of 3rd category, FSUE FRPC - Measuring System Research Institute n.a. Yu.Ye. Sedakov - (Nizhny Novgorod). E-mail: dudkin.mikhail.ig@gmail.com I. A. Illarionov - Ph.D. (Eng.), Leading Research Scientist, FSUE FRPC - Measuring System Research Institute n.a. Yu.Ye. Sedakov - (Nizhny Novgorod). E-mail: illarionovi@list.ru A. Ye. Shulyndin - Leading Research Engineer, FSUE FRPC - Measuring System Research Institute n.a. Yu.Ye. Sedakov - (Nizhny Novgorod). E-mail: shulindinae@gmail.com

Research of the characteristics of scattering fields is made to determine the backscattering diagrams and the radar cross section (RCS) of an object with the aim to control and reduce radar visibility. Vector measurements (amplitude and phase) of the objects backscattering fields in their near-field area allow calculating the object RCS with the processing algorithm, called inverse aperture synthesis (IAS), which reconstructs the reflectivity of an object uniquely associated with the RCS. This paper analyzes the main factors influencing the accuracy of reflectance reconstruction (by the coincidence of the radio image with a geometric shape) and, as a consequence, the accuracy of the RCS calculation: the distortions presented in the measured field and related to the influence of the background (quality of the anechoic chamber, the rotary support, presence of the fastening elements), finite isolation of the emitter and receiver antennas, the transmission characteristics of the antennas, including the frequency dependence of the phase center position, the radiation frequency band and frequency step, choice of the distance and the azimuth angle sampling. The experimental results have shown that the presented method allows to obtain results of objects RCS measurements with an accuracy of about 20%, which fits the requirements of the majority of tasks.

 

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