Dual-Polarized Antenna Gain Enhancement Using Dielectric Slab Superstrate and its Application in Forming an Array

The use of dielectric slab superstrate (DSS) is proposed for gain enhancement of dual-polarized patch antenna and the corresponding arrays. The DSS for a single antenna is investigated firstly to lay a solid foundation for the design of DSS for large arrays. The DSS is placed in front of the dual-polarized aperture-coupled patch antenna and is proved to be available for gain enhancement for both polarizations. The measured results show that the DSS has little effect on the impedance bandwidth but can increase the gain by 10.7 and 11.2 dB for the two ports, respectively. Different from the existing research work, the DSS used to enhance the gain for large arrays is discussed. A piecewise homogeneous DSS with slots is proposed and fabricated for 2 ×2 array with a measured peak gain of 18.3 and 18.4 dBi for two polarizations. The piecewise homogeneous DSS and source antenna array hold the advantages of high gain, large aperture efficiency and easy processability. The piecewise homogeneous DSSs for 4×4 and 8×8 array are also designed and the simulated results show that the DSS can be effective for larger arrays.