提出了一種設計多層雷達吸波材料的方法。在使用普通的損耗材料進行設計時，很難在低頻段獲得較低的反射率。磁性金屬纖維在低頻段比普通損耗材料具有更大的磁導率，此前還沒有包含磁性金屬纖維的吸波材料的設計。文中的設計將磁性纖維作為一層，其他層由普通的損耗材料構成，利用設計的一個程序對這幾層材料的參數和厚度進行了優化，該程序利用了改性的遺傳算法。得到的結果顯示出反射率在低頻段有了明顯的改善(?8 dB對比普通設計的?3 dB)。此設計提供了一種獲得優良吸波材料的方法。In this paper, we present a method for designing multilayer-radar-absorbing material. Generally, low reflectance within low frequency band is difficultly obtained by using ordinary lossy material. Magnetic metal fiber may have larger permeability at low microwave band than ordinary lossy materials have, but until now, no design has been performed for absorbing material containing magnetic fiber. We design the absorbing material by using magnetic fiber composite as a layer together with several ordinary material layers. The parameters and thicknesses of these layers are optimized by a modified genetic algorithm. The obtained results show that the reflectance at low frequency have been improved considerably.