A Gain-enhanced Dual-band Microstrip Antenna using Metasurface as Superstrate Configuration

In this paper, antenna gain enhancement using a metasurface (MS) which is designed over the FR4 dielectric by introducing a periodic arrangement of unit cells on a microstrip patch antenna is presented. Combined with the theoretical proof, a method of loading low-frequency MS structure on microstrip antenna is proposed and the antenna gain is improved by using the superposition principle of electric field above the antenna. The proposed antenna is fabricated and measured. It achieves a 4.49 dBi gain enhancement and 8.27 dBi gain enhancement when the superstrate is added over the microstrip antenna at the design frequency of 2.4 GHz and 1.8 GHz, respectively. Since there are a large number of electromagnetic waves in this frequency band in the environment, it can be extended to the study of RF energy collection and other aspects.