Novel Antenna for Microwave Breast Screening: Minimizing Surface-Wave Crosstalk

The crosstalk between sensing elements of microwave-based breast imaging systems has been widely explored in the literature. In single-substrate sensor arrays, the main source of crosstalk are the surface waves propagating at the interface of the substrate and the biological tissue. In this paper, we first report on the analysis of the existing surface waves for a shielded unidirectional antenna array next to the human breast. Then, we present a novel antenna array operating in 3.1-5.1 GHz, followed by a more complex design with hexagonal metallic walls, advantageous for the suppression of the surface waves. The results indicate that the reduction in the crosstalk is significant and worth the trade-off of the design complexity.