基于宽带棋盘型人工磁导体的微带天线RCS缩减技术

Radar Cross Section Reduction for Microstrip Antenna Using Broadband Chessboard Artificial Magnetic Conductor Structure

利用棋盘型人工磁导体(AMC)结构研究微带天线RCS的缩减技术。给出AMC耶路撒冷十字结构的等效电路模型,据此设计两个不同的AMC耶路撒冷十字,使其产生180°的反射相位差,并组成棋盘型结构。当平面波垂直入射到加载棋盘型AMC结构的微带天线表面时,实现了反射波的相消干涉。在天线带内和带外12~24 GHz都明显降低了微带天线的RCS,最大可以达到36 d B的缩减,并且天线的辐射特性基本保持不变。

In order to reduce radar cross section （RCS） of microstrip antenna, a chessboard structure composed of artificial magnetic conductors （AMC） structure is proposed. A novel equivalent circuit model is also introduced to facilitate the analysis and design of the Jerusalem cross AMC structure. Two AMC structures with different resonant sizes are designed to produce a 180° phase difference between the corresponding reflected waves, and destructive interference of backward scattering waves is achieved when a plane wave normally incidents on the microstrip antenna embedded in the chessboard AMC structure. As a consequence, the in-band and out-of-band RCS of the antenna is reduced dramatically from 12 to 24 GHz, and the maximal 36 dB RCS reduction is achieved without changing the performance of the antenna appreciably.