2.3 GHz – 2.45 GHz circular polarization U-slot patch antenna

A single-coaxial feed circularly polarized (CP) patch antenna is designed using the U-slot patch technique. With the presence of U-slot, the antenna patch on 3 layers of FR-4 substrate (dielectric constant = 4.7), is able to cover the range of frequency of 2.28 to 2.58 GHz. The size of patch 0.21λ X 0.21λ, while the ground is 0.39λ X 0.39λ, and the thickness of substrate is 0.038λ. The measured gain is 4.232dBi and S
₁₁
bandwidth is about 300 kHz. The proposed antenna is suited for the Wimax and Wi-Fi application.