A UWB Antipodal Vivaldi Antenna with Meta-Reflector Decoupling Module for Through Wall Radar Applications

This work proposes a ultrawideband (UWB) antipodal vivaldi antenna (AVA) which has rectangular corrugation at outer edge and circular outer flares for improving the performace interms of bandwidth and gain. This vivaldi antenna is designed for Through wall radar (TWR) application. For the setup multiple antenna can be used but it cause the mutual coupling through signal leakage via conduting current and surface wave along the surface and the gap in the inter-element region in a MIMO system also contributes to signal leakage. By modifying the surface current distribution, the mutual coupling due to signal leakage can be attenuated but for radiation leakage coupling, traditional approach may not be more efficient. In this paper, we proposed a meta reflector based decoupling module which is square filled grid line (SFGL), and it helps to reduce coupling nearly <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$5-10 ~\text{dB}$</tex> in lower frequency band of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1.7-3.4 \text{GHz}$</tex>.