Design of a novel 3D circular Vivaldi antennas array for Ultra-wideband near-field radar imaging

The design of a circular Vivaldi antenna array for Ultra wideband near-field radar imaging is presented. We first show a 3D single Vivaldi antenna with a 12:1 bandwidth without the need for complex microstrip transitions. A 3D circular array of 10 electrically connected elements is simulated using the Method of Moments, with 12:1 bandwidth. The 3D circular array is simulated using the Array Scanning Method (ASM) applied to the Method of Moments, where the ASM appears as a computationally efficient approach for simulating large circular antenna arrays. Near fields in E and H planes in the area of radiation exposure are depicted and exhibit smooth spreading over the whole field of view.