Design of ultra-wideband antipodal Vivaldi antenna for target RCS imaging

A low profile tapered slot antipodal Vivaldi antenna has been designed for array-based UWB target RCS imaging system. The antenna design with dimensions of 100mm×40mm achieves satisfactory impedance matching and radiation across the frequency band from 2.8 to 40 GHz with more than 173% fractional bandwidth. Both simulation and measurement results show that good radiation characteristics have been realized in the whole band. The antipodal Vivaldi antenna has been used in a MIMO antenna array for target RCS imaging successfully. The quality of image validates the performance of the antipodal Vivaldi antenna.