Wideband coplanar patch-slot antennas for radar applications

This paper presents a set of coplanar patch antennas (CPA), designed to operate at a center frequency of 10 GHz with very wideband characteristics. The antenna is based on a rectangular patch surrounded by thin slot, and its performance is tuned by using slots, shorts, and by mitering the sharp edges and corners. These antenna parameters which include the patch dimensions, the length of the coplanar waveguide feed section, the thickness of the dielectric substrate, the length of a PEC tuning short in the slot, and the length of the additional vertical tuning slots are investigated for improved performance across the entire X-band. The antenna characteristics (impedance, return loss, voltage standing wave ratio (VSWR), and far field radiation pattern) are computed for three designs yielding bandwidths that ranges from 3 to 4 GHz or 30-40% at -10 dB.