Through-wall imaging (TWI) is one of the useful applications nowadays in microwave tomography field. Reconstructing image of an object becomes more challenging when it is obscured by walls. In practice, the inclusions of noise worsen the reconstruction results. In this paper, Forward-Backward Time-Stepping (FBTS) in time inversion technique is utilized and integrated with Wall Direct Subtraction (WDS) method to reconstruct unknown object behind walls. The investigation includes two types of walls that are homogeneous and heterogeneous. The object is surrounded by closed walls. With noise added in the setup, Singular Value Decomposition (SVD) and Savitzky-Golay (SG) filtering method are used to eliminate the noise and enhance the reconstructed image of an object. The results show that WDS integrated with FBTS has successfully mitigating wall clutter from both homogeneous and heterogeneous walls, and also improves image reconstruction of a hidden object. Further, by using the proposed noise reduction method, lower MSE values can be achieved.
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