3D double S-shaped unidirectional antenna for microwave imaging

A concise 3D wideband antenna with direction is exposed to microwave imaging application. The proposed prototype has a low profile and a three dimensional folded structure is the main geometry of the antenna. To attain uni-directionality and resonance at a lower frequency, a special S-shaped along with a 3D technique is used. The dimension of the proposed antenna is 0.11×0.279×0.044 λ³ at 1.1 GHz which has fed with 50Ω microstrip transmission line. The antenna has a capability of covering the frequency of 1.1 GHz to 2.2 GHz with an average gain 5.5 dBi at 2.0 GHz. The proposed antenna accomplishes 66% fractional bandwidth (1.1–2.2) GHz. This prototype is designed and simulated in HFSS and CST Microwave Studio software.