关键词: 阵列天线, 天线模式项散射, 雷达散射截面减缩, 延时线

Abstract:

The radiation performance of an antenna must be ensured when reducing the antenna radar cross section (RCS), which makes the in-band RCS difficult to control. For this reason, this paper presents the method of loading delay lines with a varying length to achieve the antenna-mode RCS reduction of an array antenna. Antenna-mode scattering is essentially the reradiation of reflected energy, which comes from the electromagnetic wave received by the antenna and reflects at the mismatched point of the feed network. When a group of delay lines is loaded between the array elements and the feed network, the radiation energy passes through these delay lines once, while the scattering energy passes them twice. Therefore, by optimizing the length of each delay line and adjusting the phase difference between radiation and scattering, the antenna RCS can be reduced with a little degradation in radiation performance. The proposed examples of monostatic and bistatic RCS reduction show that the antenna-mode RCS can be reduced more than 14dB by this method.

Key words: array antenna, antenna-mode scattering, radar corss section reduction, delay line