一种双模式短波对数周期天线设计

为了适应电离层传播特性,使短波天线更好地与电离层环境匹配,进行大纵深覆盖,设计了一种双模式短波对数周期天线.天线在垂直方向上由两层水平极化对数周期天线构成,通过同相和反相两种激励模式,使得天线能够同时形成低仰角辐射和高仰角辐射.理论仿真和实际测试表明:双模式短波对数周期天线在6～30 MHz频带内,两种模式的电压驻波比...

Design of a dual mode HF log-periodic antenna

In order to adapt to the propagation characteristics of the ionosphere and make HF antenna better match the ionospheric environment, an HF log-periodic antenna working on dual-mode propagation is designed. The antenna is composed of two log-periodic antennas in the vertical direction. The low elevation mode and high elevation mode are produced in the proposed antenna by in-phase excitation and inverse excitation respectively. The simulation and test show that the voltage standing wave ratio(VSWR) of the proposed antenna is less than 2.5 in the range of 6-30 MHz. The elevation of the antenna is of 20° and the gain is of 12 dBi for low elevation mode;for another mode, the elevation varying from 44° to 60° and the gain of 10 dBi are obtained. The proposed antenna works on two modes,which effectively improves the coverage ability of the conventional HF log-periodic antenna. The design lays a foundation for the further research of multipath separation of high frequency signals.