Microwave radar and microwave-induced thermoacoustic technique exploit the contrast in the permittivity and conductivity between malignant and healthy tissue. They have emerged as promising techniques for detecting breast cancers. This paper compares the imaging capability of these techniques in the presence of homogeneous and heterogeneous breast tissue. Relying on the data from the finite-difference time-domain simulations, the study shows that both techniques are capable of imaging homogeneous objects. In the presence of electromagnetic dispersion and heterogeneity, radar signals suffer from strong dispersion and multiple scattering, which decorrelate the signals with the scatterers. The microwave-induced thermoacoustic technique takes the advantage of breast being acoustically homogeneous and is capable of generating high-quality images.
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