论文部分内容阅读
在微波频段,金属线天线涂以六方晶铁氧体涂料会减小后向散射雷达截面,在高频和超高频通信频带内也不会引起辐射效率的显著变化。本文推导了在无限长圆柱导体的表面上涂以多层六方晶铁氧体涂料的后向散射雷达截面,其结果加以修正可以用来估算有限长单极天线的后向散射雷达截面。给出多层涂复的计算结果是为了说明在一定的涂层厚度下,在微波频段内后向散射特性所能得到的改善。根据计算结果可见这种技术最适用于各层涂料的特性及其几何参量均具有锥削分布的情况,同时要在所需的频段內将铁磁材料的谐振频率参差配置。最后,在微波频段(对入射波为TM和TE极化而言),这个原理通过对超高频铁氧体涂复天线减小后向散射的测量和对该天线在超高频段的辐射特性的测量而得以证实。
The application of hexagonal ferrite coatings to wire antennas in the microwave band will reduce the backscatter radar cross section and will not cause significant changes in radiation efficiency within the HF and UHF communications bands. In this paper, the backscatter radar cross section of multi-layer hexagonal ferrite coating on the surface of an infinite cylindrical conductor is deduced. The result can be used to estimate the backscatter radar cross section of a finite length monopole antenna. The calculation results of multilayer coating are given to illustrate the improvement of backscattering properties in the microwave band at a given coating thickness. According to the calculation results, it can be seen that this technique is most suitable for the coating of all layers and its geometrical parameters have taper distribution, and meanwhile the resonant frequency of the ferromagnetic material needs to be arranged in the required frequency band. Finally, in the microwave frequency band (TM and TE polarization for incident waves), this principle reduces the backscatter measurement of the UHF ferrite coated antenna and the radiation characteristics of the antenna in the UHF band The measurement was confirmed.