A Thin Transparent Phase Correction Surface for Patch Antenna Gain Enhancement

Antenna gain can be increased significantly by achieving a uniform phase distribution in its electric near-field. Phase correction must be implemented to the non-uniform field radiated by the antenna to compensate for the phase variations and create a uniform radiated field phase front. This paper demonstrates the gain enhancement of a simple circularly polarized patch antenna by using a thin, low-cost, passive phase-correcting surface (PCS). The PCS consists of only three metal-dielectric layers and uses thin substrates separated by air gaps of only
$0.16\lambda_{0}$
. The gain enhancement of 11 dB has been demonstrated for a simple patch antenna with a maximum gain of 18.4 dBi at 20GHz. The designed antenna is planar with a bandwidth of 600MHz.