Double-slot Vivaldi antenna with improved gain

A double-slot structure is proposed to design a new Vivaldi antenna with improved gain. The two slots are excited in uniform amplitude and phase by using a T-junction power divider. The double-slot structure can generate plane-like waves across the slot aperture of the antenna. As a result, the gain of the double-slot Vivaldi antenna is significantly improved compared with that of a typical Vivaldi antenna of the same size. The measured results show that the impedance bandwidth of the double-slot Vivaldi antenna is from 2.5 to 15 GHz. The gain of the proposed antenna is considerably higher than the typical antenna at frequencies above 6 GHz. What is more, the structure proposed is far simpler than those designed before.