An antipodal Vivaldi antenna with band-notched characteristics for ultra-wideband applications

An antipodal Vivaldi antenna (AVA) with band-notched characteristics is proposed in this paper for ultra-wideband (UWB) applications. For UWB systems, there will be some interference from the narrow band systems. The proposed antenna adopts resonant parallel strip (RPS) to reject an unwanted narrow band. It is easy to tune the RPS to eliminate the interference band. To validate this approach, a printed AVA with RPS is simulated and fabricated. From 2 to 9 GHz, the proposed antenna shows a good result with approximate 2:1 VSWR, an average gain of 6.5 dB, and stable radiation patterns except the notched band. At the center frequency of the notched band, the measured results show that the VSWR is more than 8:1, the realized gain is less than −10 dB and a messy radiation pattern is achieved. The simulated and measured results are in good agreement.