Design and Performance Analysis of Dual band Circularly Polarized C-Slot Patch Antenna

In this paper dual band aperture coupled Circularly Polarized (CP) C-Slotted antenna with a small frequency ratio exited through a single feed is proposed for GPS application. The optimized design of CSlot antenna has been validated using IE3D Electromagnetic wave simulator. The C-slot is asymmetrical about the centre of the antenna. The antenna parameters can be optimized by changing the physical parameters like as length of the slot , permittivity of the dielectric etc.The measured 10-dB return loss bandwidth of the optimized slot are 44.91% & 6.8%for the lower and upper band respectively. The measured Axial Ratio is 0.14 at 1.29 GHz. The overall antenna gain is more than 5.5 dBic and efficiency is 80%.A dual frequency aperture coupled patch antenna may provide a substitute to large bandwidth planner antenna. .