A wideband variable width microstrip grid array antenna

A wideband planar microstrip grid array antenna is presented. The antenna is realized on a standard Rogers RO3003 substrate. It is fed using two centrally located microstrip vias through a ground aperture. Measured results show a 12% S11 <;-10 dB bandwidth and a maximum gain of 17 dBi. Using a variable microstrip line width, a side-lobe suppression of at least -12 dB between 77-85 GHz is measured. The antenna can be used in short and medium range operation for automotive radar.