一种双方环宽带反射阵的RCS缩减方法

RCS reduction technique of double-square wideband reflection array

提出了一种由双方环组成的微带反射阵天线的RCS缩减方法.对有金属地板和频率选择表面支撑的双方环反射阵单元的性能进行了比较.仿真和测量结果显示出当工作频带内的电磁波入射到这两种结构时,其反射波的相位响应较为接近.然而,带外的电磁波照射这两种结构时,由于后一种结构的周期性金属图层对入射电磁波有一定的透射作用,可使反射率减少多达4dB,因此采用由FSS作为地板的结构可在一定程度上减少其带外RCS,而对工作频带内的特性参数却影响不大.

RCS reduction method for Microstrip reflection array antennas with double-square elements is presented. The performance of double-square reflectarray element backed either by a solid metal ground plane or a frequency-selective surface is compared. Simulated and measured results show that when the ＇in-band＇ electromagnetic wave radiates the two structures, its reflection phase response is similar; however, when the ＇out-of-band＇ wave radiates the two structures, periodic metal layer can reduce reflectivity of the antenna by more than 4 dB due to some transmission for incident wave. Therefore, out-of-band RCS can be reduced and have small effects on in-band characteristics by using the structure with FSS as ground plane.