volume | PIER Journals

Abstract

The paper presents a new compact directional antipodal Vivaldi antenna that can be employed in modern imaging applications. To obtain wide-band impedance bandwidth in the proposed antenna, a stair case slot is introduced in both the tapered region along with a triangular ground plane. In addition, by means of introducing a parasitic patch close to the centre of radiators, a more directional radiation characteristic is attained within the operational bandwidth. Based on the simulation results, the antenna designed on FR4 substrate provides a wide impedance bandwidth (S₁₁ < -10 dB) of 6.2 GHz i.e., between (3.8-10 GHz) with a gain between 3.5 to 7.5 dB suitable for variety of imaging applications. The designed single feed antenna is compact, low profile and trimmed to provide a triangular geometry with light weight. To validate the directional radiation performance of the antenna, it is fabricated and integrated with a signal generator and spectrum analyzer to obtain the image of a uniform target object i.e., cylinder using the standard back projection Radon transform algorithm. The proposed setup along with the algorithm are promising for the civil and medical applications on applying to other shapes of objects.

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Dr. Amit Birwal

Dr. Kamlesh Patel

Dr. Sanjeev Singh