A low cross-polarized antipodal Vivaldi antenna array for wideband operation

An antipodal Vivaldi antenna gives good performance over a wide bandwidth, but the cross-polarization level is unfortunately high due to the slot flares on different layers. As a simple technique to reduce the cross-polarization level in the array, the antipodal antenna and its mirror image are placed alternately in the H-plane. The cross-polarization level is reduced more than 20 dB at broadside.