UDC 001.891.573

Numerical analysis of phase distribution in quiet zone of a compact range with laterally defocused feed

 

A. S. Zubov , A. V. Nikitenko

Institute for Theoretical and Applied Electromagnetics of the Russian Academy of Sciences, Izhorskaya 13, Moscow125412, Russia

 

The paper is received on November 6, 2019

 

Abstract. A compact range is designed to conduct quasi-monostatic measurements of the scattering characteristics of various objects. However, the data obtained with bistatic measurements contains additional information about scattering patterns and can be used for design and optimization of the scattering characteristics of such objects at more detailed level. To conduct bistatic measurements in a compact range, it is necessary to shift the feed from the reflector’s focus. This inevitably leads to a less uniform phase in the quiet zone. In this article, we consider approximate method based on ray optics to calculate this decrease in uniformity in the quiet zone of a compact range with laterally defocused feed. The calculation results for this method and physical optics are presented for two reflectors with diameters of 5 and 12 meters. Comparison of the calculated data shows good agreement, however the considered method shows much faster performance on personal computer. The experimental measurements data for compact range with 12-meter reflector is also presented, which also agrees well with approximate calculations. Using this approximate method, we can estimate the size of a quiet zone depending on the bistatic angle; several dependence curves are presented for 6, 10 and 18 GHz. It is shown that simple lateral defocusing of the reflector feed creates a much smaller quiet zone than the zone limited only by the geometry of the reflector itself. In order to get closer to this geometric limit, it is necessary not only to shift feed laterally, but also to use shifts in other directions and/or more complex feeds and measurement methods. Using ray optics technique, we estimate the vertical feed shifts for various azimuthal bistatic angles.

Key words: compact range, defocused feed, higher-order diffraction centers.

References

1. Balabukha N.P., Zubov A.S., Solosin V.S. Kompaktnye polygony dlya izmerenya harakteristik rasseyaniya. [Compact ranges for measuring scatter characteristics]. Moscow, Nauka Publ. 2007. 266 p. (In Russian)

2. Chang D.C., Chang T.Z., Liu R.C., Fu I.J. Measurement of bistatic radar cross section in a 5751 compact range. Antennas and Propagation Society International Symposium. 1993.

3. Solosin V.S, Balabukha N.P., Zubov A.S. Kompaktnyi polygon ITPE RAN. [Compact range at ITAE RAS]. Proceedings of the X Vserossiiskaya nauchno-tekhnicheskaya konferenciya “Metrologiya v radioelektronike” [10th All-Russian Scientific and Technical Conference “Metrology in radio electronics”]. Mendeleevo, Moscow region. 2016. P.199-202. Published by VNIIFTRI. (In Russian)

 

For citation:

Zubov A.S., Nikitenko A.V. Numerical analysis of phase distribution in quiet zone of a compact range with laterally defocused feed. Zhurnal Radioelektroniki - Journal of Radio Electronics. 2019. No. 11. Available at http://jre.cplire.ru/jre/nov19/8/text.pdf

DOI  10.30898/1684-1719.2019.11.8