Breast Tumor Detection via S‐Parameter Contrast Using a 1 × 8 Miniaturized Metamaterial Antenna Array for UWB Microwave Imaging

Due to the significant increase in breast cancer cases and the limitations of existing early‐stage detection techniques, microwave imaging has emerged as a critical tool for the diagnosis of carcinogenic and malignant cells in various tissues. In this work, a 1 × 8 miniaturized metamaterial‐based antenna array is conceived and developed for ultrawideband microwave imaging for early breast cancer diagnosis because of its improved accuracy. The developed antenna array features a small dimension, a wide frequency band, a high gain, and broadside radiation properties. To achieve the wider bandwidth from 3.34 to 6.79 GHz, H‐shaped unit cells and T‐shaped feed network dimensions are optimized. The obtained wide bandwidth supports the generation of high‐quality images. A partial ground plane structure is used to improve impedance matching and further enhance the bandwidth. Antenna performance is first numerically and experimentally validated in free space. The antenna performance is validated via numerical simulation and experimental measurements in free space. A numerical phantom with similar tissue properties is created with and without the tumor. Differences in the back scattered signals from the antenna array elements can be observed due to the higher water content and larger dielectric constant of malignant cells as compared to healthy ones, which can be analyzed to identify the tumor or cancer. Here, eight antenna elements are arranged in a circle at a distance of 10 mm from the breast. The separation between adjacent antenna elements is 17 mm to reduce the mutual coupling. Furthermore, the breast tissue is scanned at different angles. At a time, one antenna is excited and the others are in the receiving mode. The collected signals are used to detect malignant cells. The existence of a tumor causes differences in the back scattered signals of the antenna elements. The absolute difference in transmission coefficients, with and without the presence of a tumor, is used to detect the existence of malignant cells. The suggested structure has demonstrated effective performance in microwave imaging using S‐parameter contrast.