Quantitative Microwave Imaging of Realistic Numerical Breast Phantoms Using an Enclosed Array of Multiband, Miniaturized Patch Antennas

An Active and Low-Cost Microwave Imaging System design for Detection of Breast Cancer Using Back Scattered Signal

A defected ground antenna with dielectric reflector is designed and investigated for breast tumour diagnosis. Ultra-wide band resonance (3.1 to 10.6 GHz) is achieved by etching two slots and adding a narrow vertical strip in a patch antenna. A high dielectric constant substrate is added below the antenna, which shows remarkable effect on performance. Antenna performance is verified experimentally on an artificially fabricated breast tissue and tumour. Malignant tissue has different dielectric properties than the normal tissue, that causes deviation in the scattered antenna power. Average value of backscattered signal variation and ground penetrating radar (GPR) algorithm is used to localize the tumour of radius 4mm in breast tissue.

A TSVD Analysis of the Impact of Polarization on Microwave Breast Imaging using an Enclosed Array of Miniaturized Patch Antennas

Microwave breast imaging performance is fundamentally dependent on the quality of information contained within the scattering data. We apply a truncated singular-value decomposition (TSVD) method to evaluate the information contained in a simulated scattering scenario wherein a compact, shielded array of miniaturized patch antennas surrounds an anatomically realistic numerical breast phantom. In particular, we investigate the impact of different antenna orientations (and thus polarizations), namely two array configurations with uniform antenna orientations and one mixed-orientation array configuration. The latter case is of interest because it may offer greater flexibility in antenna and array design. The results of this analysis indicate that mixed-polarization configurations do not degrade information quality compared to uniform-polarization configurations and in fact may enhance imaging performance, and thus represent viable design options for microwave breast imaging systems.

Multi-Band Miniaturized Patch Antennas for a Compact, Shielded Microwave Breast Imaging Array

We present a comprehensive study of a class of multi-band miniaturized patch antennas designed for use in a 3D enclosed sensor array for microwave breast imaging. Miniaturization and multi-band operation are achieved by loading the antenna with non-radiating slots at strategic locations along the patch. This results in symmetric radiation patterns and similar radiation characteristics at all frequencies of operation. Prototypes were fabricated and tested in a biocompatible immersion medium. Excellent agreement was obtained between simulations and measurements. The trade-off between miniaturization and radiation efficiency within this class of patch antennas is explored via a numerical analysis of the effects of the location and number of slots, as well as the thickness and permittivity of the dielectric substrate, on the resonant frequencies and gain. Additionally, we compare 3D quantitative microwave breast imaging performance achieved with two different enclosed arrays of slot-loaded miniaturized patch antennas. Simulated array measurements were obtained for a 3D anatomically realistic numerical breast phantom. The reconstructed breast images generated from miniaturized patch array data suggest that, for the realistic noise power levels assumed in this study, the variations in gain observed across this class of multi-band patch antennas do not significantly impact the overall image quality. We conclude that these miniaturized antennas are promising candidates as compact array elements for shielded, multi-frequency microwave breast imaging systems.