Enhancement of Penetration of Millimeter Waves by Field Focusing Applied to Breast Cancer Detection.

The potentialities of improving the penetration of millimeter waves for breast cancer imaging are here explored. A field focusing technique based on a convex optimization method is proposed, capable of increasing the field level inside a breast-emulating stratification. The theoretical results are numerically validated via the design and simulation of two circularly polarized antennas. The experimental validation of the designed antennas, using tissue-mimicking phantoms, is provided, being in good agreement with the theoretical predictions. The possibility of focusing, within a lossy medium, the electromagnetic power at millimeter-wave frequencies is demonstrated. Field focusing can be a key for using millimeter waves for breast cancer detection.