Numerical analysis of phase distribution in quiet zone of a compact range with laterally defocused feed
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.
- компактный полигон
- расширенные радиоизображения
- вынос облучателя из фокуса
- compact range
- defocused feed
- higher-order diffraction centers
Аннотация (на русском)
Анализ поля в рабочей зоне компактного полигона при выносе облучателя из фокуса
В работе рассмотрено влияние выноса облучателя коллиматора из фокуса на неравномерность фазы поля в рабочей зоне компактного полигона. Проведена численная оценка поля в рабочей зоне, рассмотрено два способа расчета - в геометрооптическом приближении и методом физической оптики. Проведено сравнение этих методов. Также были проведены измерения неравномерности поля в рабочей зоне компактного полигона при смещении облучателя относительно фокуса зеркала. В работе приведены результаты эксперимента.
For citation
Zubov A.S., Nikitenko A.V. Numerical analysis of phase distribution in quiet zone of a compact range with laterally defocused feed // Journal of Radio Electronics. – 2019. – No. 11. https://doi.org/10.30898/1684-1719.2019.11.8
References
- Балабуха Н.П., Зубов А.С., Солосин В.С. Компактные полигоны для измерения характеристик рассеяния. М.:Наука, 2007.
- D.C. Chang, T.Z. Chang, R.C. Liu, I.J. Fu. Measurement of bistatic radar cross section in sa 5751 compact range // Antennas and Propagation Society International Symposium, 1993.
- Солосин В.С., Балабуха Н.П., Зубов А.С. Компактный полигон ИТПЭ РАН. // Тезисы докладов X Всероссийской научно-технической конференции "Метрология в радиоэлектронике". Менделеево Московской обл., 20-22 июня 2016 г. с. 199-202.