Corrugated Antipodal Vivaldi Antenna in a Matching Medium for Ultrawideband Breast Cancer Detection

This study presents an antipodal Vivaldi antenna (AVA) with corrugations, specifically designed for breast tumor detection. The proposed antenna is designed with an overall size of $160 \times 200 \mathrm{~mm}^{2}$ on a 1.6 mm thick, low-cost FR4 substrate, operating in a triton coupling medium with a relative dielectric constant of $\epsilon_{r}=5.5$. Larger corrugations are employed to enhance the performance at lower frequencies, with all antenna parameters optimized to achieve a compact AVA design. The antenna is fed by a solderless SMA port and used to obtain realistic simulation results. By choosing the appropriate slot lengths and tilt angle of the corrugations, the radiation pattern is enhanced within the operating frequency band of $0.65-3 \mathrm{GHz}$. Compared to the conventional AVA design (without corrugations), the proposed AVA achieves gain of approximately $\mathbf{1 0} \mathbf{~ d B i}$, despite its smaller size.