Design of a tapered slot array antenna for UWB through-wall RADAR

Ultra-wideband (UWB) RADAR based technologies have been gaining popularity recently for through-wall detection and surveillance applications. In this paper, the design and implementation of antenna for such applications is presented. An exponentially tapered slot (Vivaldi) antenna[l] is adopted. The tapered slot element being a travelling wave structure has inherently wide bandwidth with added advantages of high gain and low weight. Arrays based on Vivaldi elements have been extensively studied[2,3]. The current design is based on a segmented approach[2] with design of antenna element or array configuration based on radiation pattern requirements, followed by design of balun feed for individual elements and finally the design of feed network for broadside radiation. In each step, the objective of good impedance match and hence low insertion loss leads to the desired bandwidth performance in the final design.