Ultra-Wideband Impedance Matching Technique for Resistively Loaded Vee Dipole Antenna

The resistively loaded vee dipole (RVD) antenna has many advantages as an ultra-wideband (UWB) radar antenna, especially ground-penetrating radar. However, it has the drawback of having considerable reflections at the feed point due to an impedance mismatch between the antenna and the feeding transmission line. In this communication, a matching network is proposed to reduce the reflection and the design procedure is presented. The network is composed of two L-sections in cascade: an inductive L-section for high frequency matching and a high-pass type L-section for low frequency matching. It is demonstrated that the high-pass type L-section hardly destroys the high frequency matching. The RVD with the proposed matching network is implemented and the performance is measured. The results show that the RVD is matched over the desired band of 500 MHz-3 GHz, and more energy is radiated in the main pulse.