小型化短波天线及其频带扩展方法

A miniaturized HF antenna and a method of broadening the frequency range

摘要:

为了克服短波天线小型化引起的带宽变窄的问题,提出了一种类似于电偶极子的新型小型化半球线栅结构的短波天线．该天线结构简单,馈电方便．最大尺寸3.6 m,是低频波长的3.6％,高频波长的36％．利用CST MWS软件进行仿真并制作了缩比模型．仿真和测试结果表明,该天线能够在不加载、不用匹配网络的情况下相对阻抗带宽达到40％,并且兼顾了增益与效率．继而研究了通过加载集总元件扩展天线频带的方法,并进行了仿真和实验验证．

Abstract:

The bandwidth will get narrow when the size of HF antenna is small. To overcome this problem, a novel miniaturized HF antenna composed of hemispherical wire grids with performance similar to the electric dipole is presented in this paper. The antenna has simple structure and is easy to feed. The largest dimension of this antenna is 3.6 m, which is 3.6％ of its lowest frequency wavelength, and 36％ of its highest frequency wavelength. The antenna is simulated with the help of CST MWS. A 1/5 scale model is manufactured and measured. The results demonstrate that the relative impedance bandwidth is 40％ without loading or external matching networks while maintaining acceptable performance. A method of broadening frequency range by loading lumped elements is further discussed, and simulation and test verification have been done. The designed antenna can be widely used in HF communication system, over-the-horizon radar and so on.