STRUCTURE ANALYSIS OF SINGLE- AND 2 MULTI-FREQUENCY SUBSPACE MIGRATIONS IN 3 INVERSE SCATTERING PROBLEMS

We carefully investigate the structure of single- and multi frequency imaging functions, that are usually employed in inverse scattering problems. Based on patterns of the singular vectors of the Multi-Static Response (MSR) matrix, we establish a relationship between imaging functions and the Bessel function. This relationship indicates certain properties of imaging functions and the reason behind enhancement in the imaging performance by multiple frequencies. Several numerical simulations with a large amount of noisy data are performed in order to support our investigation.