高功率超宽带变压器油透镜天线设计与仿真

将TEM喇叭天线密封进填充变压器油的尼龙天线罩中，只要合理设计尼龙天线罩外形,使变压器油形成聚焦透镜，不仅能提高天线的功率容量，还能改善其辐射特性。基于变压器油的缩波效应和椭球的几何性质，借助几何光学理论，设计了一款具有聚焦能力的椭球变压器油透镜。变压器油的缩波效应能够增大TEM喇叭天线电尺寸，使TEM喇叭天线的辐射特性得到初步改善，透镜的聚焦能力使天线的定向性得到进一步改善。为了验证理论分析的正确性，另外设计了一款不具有聚焦能力的球状变压器油透镜作为参照，两款透镜天线仿真结果与理论分析吻合。与大气中的TEM喇叭天线相比，椭球变压器油透镜使TEM喇叭天线主波束变窄，远场电压峰峰值提高56.97%，阻抗带宽低频端从0.28 GHz扩展到0.2 GHz，功率容量达到18.43 GW。

Design and simulation of HPM-UWB transformer oil lens antenna

Sealing a TEM horn antenna in a nylon radome filled with transformer oil can enhance the power capacity, and improve the performance of the TEM horn antenna as long as a beam focusing lens is formed by the nylon shell filled with transformer oil. On the basis of the ellipses geometrical properties and the shrinkage of wavelength in a medium, an ellipsoidal transformer oil lens was designed with the help of geometrical optics theory. The theory says that the shrinkage of the wavelength in transformer oil enlarges the electrical size of the TEM horn will preliminarily improve the performance of the TEM horn antenna, and the beam focusing characteristics of the ellipsoidal transformer oil lens will further improve the performance of the TEM horn antenna. In order to prove the correctness of the theoretical analysis, a spherical transformer oil lens without beam focusing characteristics was designed as comparison, and the simulation results agreed well with the theoretical analysis. Compared with the TEM horn in atmosphere, the ellipsoidal transformer oil lens narrowed down the main beam and increased the rEpp by 56.97%, and the low boundary point of the impedance bandwidth reached 0.2 GHz from 0.28 GHz. The power capacity of the ellipsoidal transformer oil lens TEM horn antenna reached 18.43 GW.