Gain enhancement of compact CPW-Fed ultra-wideband antenna using an FSS reflector

In this paper, an enhancement gain of compact CPW-Fed antenna using a single layer frequency selective surfaces (FSSs) reflector for ultra-wideband (UWB) applications is presented. A hexagonal CPW-Fed antenna with a size of 30 × 30 mm² is realized to provide a UWB bandwidth operation. In this study, a novel design of an FSS unit cell with reduction and a small size of 8 × 8 mm² is proposed. It allows one to achieve a UWB band-stop response between 3 and 11.5 GHz. The FSS reflector has 7 × 7 units with a total size of 56 × 56 mm². This reflector is placed below the antenna at a distance of 20 mm. The main objective of this contribution is to improve the gain level of the antenna, where the proposed antenna achieves an improvement of realized gain of 6.2 dBi with increasing from 2.2 to 8.4 dBi. The antenna became more directive after the integration of the FSS reflector with a directional radiation pattern. The numerical and experimental results are in good concordance with the simulated one. This study is performed in terms of voltage standing wave ratio, radiation pattern, realized gain, and radiation efficiency.