Wideband Antipodal-Vivaldi Antenna for Multi-Frequency Approach Based Microwave Imaging

Inverse scattering method (ISM) based Microwave imaging (MWI) has gained prominence in the quantitative imaging of the dielectric properties in many applications. However, it suffers from the inherent challenge of ill-posedness, which is mitigated by utilizing imaging data across a broad frequency range, albeit at the cost of increased computational demands. To address this issue, MWI leveraging multi frequency imaging approch like long short-term memory neural networks (LSTM-NN) has come forth as an effective alternative, efficiently processing the imaging data across a broad frequency spectrum by treating it as a multifrequency band dataset. Thus for implementation, LSTM-NN-based MWI framework demands broadband antennas and in this regard, this article presents a wide-band antipodal Vivaldi antenna, functioning in the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.3-10 \text{GHz}$</tex> frequency range, providing 9.8 dBi peak gain at 5 GHz and a promising gain across the entire frequency range. The desired performance is achieved by incorporating rectangular and elliptical slots on a conventional antipodal Vivaldi antenna.