Design of ultra-wideband folded antenna for ground penetrating radar

Analyzing the frequency domain of the antenna by using the electromagnetic field simulation software HFSS, we design a new antenna with center frequency of 268MHz and working frequency of 60-419MHz. The relative bandwidth is 134%, which has a wider bandwidth and can be matched better compared to the traditional bowtie ones. By means of adding elliptical arms and truncated arms on both sides, the bandwidth of the antenna is expanded effectively. With the method of slotting and end loading, the gathering effect of the current at the end of the arm is increased and the lowest operating frequency is reduced. In addition, folding the antenna is with the good help of enhancing the gain at the high radiation frequency. At last, a metallic shield carinal cavity is added to the back of the antenna in order to improve its directional gain and anti-interference ability.