A Miniaturized CPW-Fed Antipodal Vivaldi Antenna With Enhanced Radiation Performance for Wideband Applications

A miniaturized coplanar waveguide (CPW)-fed antipodal Vivaldi antenna (AVA) is presented in this letter. Elliptically shaped strip conductors are used to lower the antenna operating frequency. With two pairs of tapered slots and circularly shaped loads, the radiation performance in lower operating band can be greatly enhanced. The fabricated prototype of this proposed antenna with a size of $90 \times 93.5 \times 0.8~\hbox{mm}^{3}$ was measured to confirm the simulated results. The wide measured impedance band from 1.32 GHz to more than 17 GHz for $\hbox {VSWR} can be obtained. Meanwhile, the good measured radiation patterns with gain $3.5\hbox {--} 9.3~\hbox{dBi}$ in end-fire direction achieve in the whole measured working band.