Pulse Radiation Antipotal Vivaldi Antenna With Double-Slot Structure

The Antipodal Vivaldi antenna (AVA) is suitable for radiating pulse, due to its ultra-wideband (UWB) property. However, increasing antenna gain while ensuring the UWB characteristics is a major challenge. This paper presents a novel vivaldi antenna with double-slot structure to enhance radiation performance. The two slots can radiate pulses simultaneously, which endows energy synthesis in space. Due to the equivalent capacitance structure from overlapped adjacent radiation layers, the current on the two slots remains continuous, which is significant for promotion of bandwidth and gain. A wideband feeding balun based on microstrip line is used to feed two slots power-equally. The simulated results show that the designed antenna operates from 300 MHz to more than 3 GHz with $\mathrm{S} 11\lt-$ 10 dB, and the gain is 15.5 dBi at 3 GHz, which is higher than that of the conventional vivaldi antenna.