【摘要】 采用时域有限差分(FDTD)方法计算了铝梯度周期性结构复合木材的电磁波吸收特性。分析了在木材平板中嵌入多层孔径大小呈梯度周期性变化的金属铝方形网格后,方形孔径大小及金属铝网格的排列方式对材料电磁波吸收特性的影响。结果表明:在1~20GHz频率范围内,在木材中嵌入金属铝网格能够明显改善其电磁波吸收性能。改变金属铝网方形孔径的大小可调整吸收峰出现的位置。在木基材料中嵌入孔径大小呈梯度变化的金属铝网格时,复合材料在8.26~17.44GHz范围内出现了3个反射损耗值小于-10dB的吸收峰,即f=9.36GHz、12.04GHz和14.88GHz时,其反射损耗最小值分别为-18.31dB、-40dB和-32.87dB,其吸收带宽分别为1GHz、0.5GHz和0.3GHz。更多还原

【Abstract】 The finite difference time domain(FDTD)method was used to calculate the absorbing properties of a gradient periodic structure aluminum layers comprised wood composites.The effects of the size of square pore and the arrangement of inserted aluminum layers on the absorbing properties were estimated after a gradient periodic aluminum layers were inserting into the wood panel.The results show that the absorbing properties of pure wood panel were significantly enhanced by inserting aluminum layers in the range of 1-20 GHz.The absorption peak frequency can be tuned by controlling the pore size of the aluminum lattice.The reflectivity loss of the wood-based composites,which consist of aluminum layers whose gradient pore size varies continuously was below-10 dB in the range of 8.26-17.44 GHz,the corresponding number of absorption peak was three,and the minimum value was-18.31 dB,-40 dB,-32.87 dB,respectively at 9.36 GHz,12.04 GHz and 14.88 GHz,the corresponding bandwidth was 1GHz,0.5GHz,0.3GHz,respectively.更多还原