Subspace-Based Distorted-Rytov Iterative Method for Solving Inverse Scattering Problems

In this article, an iterative method, called the subspace-based distorted-Rytov iterative method (S-DRIM), is proposed for solving inverse scattering problems. In each iteration of the S-DRIM, the subspace-Rytov approximation (SRA) is applied and the results are used to update the parameters of the background medium. Through simulations, the approximation errors of both the Rytov Approximation (RA) and the SRA in various background media are analyzed and compared. The performance of S-DRIM is verified using both synthetic and experiment data. It is observed that the S-DRIM outperforms the non-iterative SRA inversion method for the reconstructions of mild scatterers. In addition, the S-DRIM presents a smaller value of reconstruction error in optimization processes compared to the distorted-Rytov iterative method (DRIM).