Flexible 16 Antenna Array for Microwave Breast Cancer Detection

TLDR

Microwave radar imaging for breast cancer detection has been extensively studied, focusing on dielectric property differences across a wide frequency band, and flexible antennas are preferred for wearable applications. The study aims to design single‑ and dual‑polarization antennas for wireless ultrawideband breast cancer detection using an inhomogeneous multilayer model of the human breast. Miniaturized flexible monopole and spiral antennas on 50‑μm Kapton polyimide, measuring 20 mm × 20 mm, were designed with HFSS to operate from 2 to 4 GHz with S11 below –10 dB, and two conformal 4 × 4 ultrawideband arrays in a bra‑like format were developed with reflectors to enhance penetration. Measurements show the flexible antennas maintain good impedance matching across different breast curvatures, and the array reflectors increase penetration by factors of 3.3 and 2.6.

Abstract

Radar-based microwave imaging has been widely studied for breast cancer detection in recent times. Sensing dielectric property differences of tissues has been studied over a wide frequency band for this application. We design single- and dual-polarization antennas for wireless ultrawideband breast cancer detection systems using an inhomogeneous multilayer model of the human breast. Antennas made from flexible materials are more easily adapted to wearable applications. Miniaturized flexible monopole and spiral antennas on a 50-μm Kapton polyimide are designed, using a high-frequency structure simulator, to be in contact with biological breast tissues. The proposed antennas are designed to operate in a frequency range of 2-4 GHz (with reflection coefficient (S11) below -10 dB). Measurements show that the flexible antennas have good impedance matching when in different positions with different curvature around the breast. Our miniaturized flexible antennas are 20 mm × 20 mm. Furthermore, two flexible conformal 4 × 4 ultrawideband antenna arrays (single and dual polarization), in a format similar to that of a bra, were developed for a radar-based breast cancer detection system. By using a reflector for the arrays, the penetration of the propagated electromagnetic waves from the antennas into the breast can be improved by factors of 3.3 and 2.6, respectively.