Imaging Performance Enhancement using Virtual Antennas for Inverse Scattering System in Noisy Environment

In this paper, it has been observed that the correlation coefficient defined by the scattered field data tested by the two adjacent antennas decreases with noise, which implies that additional nonredundant scattered field information can be obtained to improve the imaging performance by setting more measuring antennas. However, the practical implementation of adding more measuring antennas faces challenges such as limited antenna space, high experimental expenses, and prolonged data collection time. To this end, the frequency-domain zero-padding (FDZP) interpolation method is proposed to acquire scattered field data on more virtual antennas, thereby improving the imaging performance. A linear inversion algorithm modified Born approximation (MBA) method and a nonlinear algorithm subspace-based optimization method (SOM) are employed for imaging scatterers of moderate and high contrast, respectively. Finally, synthetic data based on an ideal cylindrical wave source obtained using the method of moment (MOM), and semi-experimental data using full-wave simulation software HFSS, as well as experimental data, are used to validate the effectiveness and reliability of the proposed method, respectively.