曲线三极子频率选择表面单元

A Curve-Tripole Element of Frequency Selective Surface

设计了一种新型小型化宽带频率选择表面单元——曲线三极子单元,该单元外形轮廓为圆弧组成的曲线,相对于谐振波长尺寸小,可以三角形方式紧密排列,单元间距小,可调参数多,可设计性好,能够用于带阻型、带通型不同频段、不同带宽的频选表面。基于该单元给出了一个三屏频选的设计实例,实例表明,采用曲线三极子单元的频选表面带宽宽,角度稳定性好,透波率高,有效抑制栅瓣和二次谐振,改进了带外抑制性能。

This paper presents an excellent compact wideband frequency selective surface element-curve-tripole ele- ment. The contour of this element is a curve consisting of arcs, which is small in terms of wavelength. It can be arranged tightly in a triangular grid so that it has smaller inter-element spacing. And it has good design ability because of its more ad- justable structural parameters. Curve-tripole element can be designed both for band-pass and band-stop frequency selective surface with different frequencies and different bandwidth. The paper gives a design example of tri-screen frequency selective surface with the curve-tripole element. The simulated results show that, the FSS with curve-tripole element has excellent band filter characteristic with a fiat top and sharp fall off; works well both for wide-band and wide-angle with high transmission rate; grating lobes and the second harmonic are suppressed effectively; the performance outside pass-band is greatly improved.