Impedance matching design of Vivaldi antenna in X-band

The stripline design of an X-band double layer Vivaldi antenna to achieve impedance matching is described in this paper. The theory of the equivalent circuit in transmission line theory is adopted to get the wide of stripline at the coupling point, and it is deduced that the bandwidth of the antenna can be enhanced by a gradient index stripline, as well as double gain by the design of double layer. A antenna of 45mm (length) × 20mm (width) × 3.15mm (thickness) is designed and fabricated in this paper. The simulation results show that the bandwidth is from 8 GHz to 12 GHz, while the maximum gain is 6.7 dB, and the VSWR<;2, which can meet the design requirements.