一种改进的探地雷达蝶形天线

Improvement of bow-tie antenna for ground penetrating radar

探地雷达(GPR)系统一般采用宽带短脉冲信号,因而其天线应该是宽带的。为提高天线的辐射效率,有效吸收天线末端的反射波,一种新型结构的蝶型天线被提出。该天线将脉冲激励电路和天线集于一体,同时采用分布电阻加载的方法,以吸收天线末端与激励点处的反射波。通过FDTD方法对天线辐射特性的研究表明,改进后的天线可以有效的吸收来自天线末端的发射波,消除在激励点处由于阻抗不匹配产生的二次反射,使天线具有较好的辐射波形,提高天线辐射效率,满足探地雷达系统的需要。

The driven signal of Ground Penetrating Radar （GPR） system usually is wide-band and short pulse, so the antenna must be wide-band. In order to reduce the strength reflective wave at antenna end and improve the detecting effect of the GPR, a novel configuration of bow-tie antenna is presented in the paper. The driving circuit is built in the resistively loaded antenna. In the paper, the radiation characteristics of the bow-tie antenna are studied through Finite Difference Time Domain （FDTD） Method. Numerical simulation results show that the antenna proposed in this paper terminates the reflections at the end of antenna and reduces the strength of reflective wave at antenna excitation point. Of course, the radiation efficiency can be improved. The antenna can be applied in GPR systems.