Abstract
This paper presents small-size and ultra-wide band (UWB) antenna that can be useful for microwave imaging applications. The proposed monopole type antenna, developed on Rogers RT5880 substrate, occupies the circuit area of 30-by-30 sq. mm. The performance of the initial antenna was enhanced by applying three different approaches, namely, incorporation of an additional stub, etching a defect on the ground, and the insertion of symmetrical slots. As a consequence, the developed UWB antenna operates in a wide range of frequencies between 2.5 GHz and 12.5 GHz. In addition, the achieved antenna performance was examined on the heterogeneous model to evaluate its practicability.