采用FDTD法研究微带天线雷达散射截面的减缩

Study on the Radar Cross Section Reduction of Microstrip Antennas by FDTD Method

采用时域有限差分法(FDTD)方法以及新的含有内阻的磁流环激励同轴馈电模型研究了微带天线的辐射及散射特性,分析了集总负载加载和贴片表面开槽对微带天线雷达散射截面(RCS)的影响,研究了微带天线RCS减缩前后的回波损耗、增益及方向性的变化.研究表明,集总负载加载能降低谐振频率点的RCS,开槽方法能在天线辐射性能改变不大的情况下对微带天线的RCS具有较好的减缩作用.

The FDTD method and a new coaxial line feeding model containing a magnetic frill with inner impedance are used to study the radiation and scattering properties of microstrip antennas. The influences of lumped impedance-loading and the cutring of slots on the patches of microstrip antennas on the radar cross-section are analyzed. The variations of the return loss, gain and radiation pattern of microstrip antenna before and after the reduction of the RCS are studied. It is shown that the lumped impedanceloading can reduce the RCS at the resonant frequencies, and the RCS in a relatively wide band can be reduced by properly cutting slots in the patch of microstrip antenna while the radiation property of the antenna changes little.