Design of a Stacked Two Layer Circular Fractal Microstrip Antenna for X-band Application

In this paper, a novel design of a stacked two layer microstrip patch antenna with wideband characteristics is proposed. This paper follows fractal and stacking methodology to improve the characteristics of microstrip antennas. This antenna consists of two circular patches. The upper radiating patch is suspended with Teflon clamps over the lower driving element. The radiating patch is excited through EM coupling by the driving element. The rectangular slots on the ground plane are loaded for better impedance matching over the operating frequency range. The impedance bandwidth of single layer patch is 7%. After using stacking and fractal methodology the impedance bandwidth increases up to 69% ranging from 7.5GHz to 14.4GHz with acceptable return loss. This antenna offers Omni-directional radiation patterns in H-plane. This antenna is useful for X-band applications such as radar, mobile communication, satellite communication etc. as it's center frequency is 10GHz.