High Gain Microstrip Patch Antenna as Illuminating Source for Near Field Imaging

The design of a high gain circular patch antenna with the superstrate technique is presented. The antenna was used as an illuminating source for near field imaging. The antenna was designed, constructed and its radiation pattern measured in an open range measurement setup. Measured results showed a maximum antenna gain of 12.0 dBi at 3.0 GHz, and an operating bandwidth of 7.7% (2.86-3.09 GHz). Measured 3-dB beamwidths in the E- and H-planes are 30° and 40° respectively. Maximum side-lobe level is −12 dB at +/− 100° angle in the H-plane, and the front-to-back ratio is 15 dB.