低频天线测量系统中宽带双极化源天线研究

低频天线测量系统中采用四脊喇叭天线作为发射源天线, 为实现四脊喇叭天线在低频段的小型化, 设计了一种新型结构:脊边缘采用铝固体结构, 内部采用蜂窝结构来减小天线尺寸和重量.利用HFSS仿真软件对喇叭天线整体结构参数进行优化, 并对其进行加工测试.仿真和测试结果表明:后腔采用可调短路板可抑制驻波奇异点的出现; 实际加工过程中, 将聚四氟乙烯板填充在四个对称脊中间确保脊的对称性, 并得到良好的电性能.该天线已应用于低频天线测试系统, 在锥形暗室中作为发射源天线来测量汽车天线的方向图.

Broadband and dual-polarized antenna in low frequency antenna measurement system

To reduce the weight of the dual-polarized quadruple-ridged horn antenna over the frequency range of 75-500 MHz, a composite sandwich structure is used to build the antenna, which comprises solid aluminium and honeycomb materials. The parameters of structure are optimized by Ansoft HFSS software, and an adjustable shorting plate is put at the bottom of the antenna to prevent the occurrence of singularities created by standing waves. A modified Teflon board is inserted into the interspace between the four symmetric ridges. Both simulation results and measurement results show that the satisfied impedance and pattern characteristics for interested bands are obtained.