Synthetic ultra-wideband antenna for high-resolution millimeter-wave imaging

A synthetic ultra-wideband millimeter-wave antenna with application in high-resolution millimeter-wave imaging systems is presented. The antenna provides a synthetic ultra-wide bandwidth of approximately 100 GHz in the millimeter-wave regime. Our approach consists of dividing the assumed ultra-wide bandwidth (20-120 GHz) into four channels or sub-bands, and designing an antenna array including four antennas (equal to the number of sub-bands). The antennas are substrate integrated waveguide (SIW)-based antipodal Vivaldi antennas covering 20-40 GHz, 40-60 GHz, 60-90 GHz, and 90-120 GHz frequency ranges respectively. The achieved ultra-wide bandwidth (100 GHz) results in a significant improvement in the axial resolution of current millimeter-wave imaging systems.