Basic design of adjusting methods on indoor electromagnetic wave absorber using powder-type magnetic wood

为了在日益增强的电磁环境下改善舒适的居住环境，木质电磁波吸收器是解决不必要的辐射或减少其对周围区域影响的可能途径之一。研究了考虑材料常数和电磁吸收特性的室内电磁波吸波材料调整方法的基本设计，并将其应用于粉末型室内木质吸波材料的设计，取得了较好的效果。提出了两种方法，一种是将磁性液体浸渍到木粉中，另一种是对粉末型磁性木材进行低温加热。这两种方法都可以改变介电常数，并且可以在不改变电路板厚度和重量的情况下改变匹配频率。我们的研究结果可以用于设计特定吸收频率的室内粉末型木波吸波材料。

To improve a comfortable residential environment under the increasing electro-magnetic environment, a woody electromagnetic wave absorber is one possible approach to solving the unwanted radiation or to reduce its impact on the surrounding area. The basic design of adjusting methods on indoor electro-magnetic wave absorber concerning about material constants and electromagnetic absorption characteristic is examined and the methods give good results to design indoor powder-type magnetic wood wave absorbers for a specified absorp-tion frequency. The two methods are proposed, one is a method to impregnate magnetic fluid to wood powder and the other is to heat the powder type magnetic wood in low temperature. Both methods change permittivity and can shift the matching frequency without changing the thickness and the weight of the board.The results from our studies can be used to design indoor powder-type magnetic wood wave absorbers for a specified absorption frequency.