Automated removal of ghost noise from SAR images using wavelet packet transform

Due to interference caused by ground transmitters, so-called ghost noise occurs on images obtained from synthetic aperture radar (SAR). This letter proposes a scheme based on the wavelet packet transform to remove this ghost noise from the SAR image. The wavelet packet transform is employed to decompose the SAR image with the ghost noise both in the spatial and in the spatial frequency domain. To automatically detect and remove the ghost noise, an energy detection method is developed in this letter. The performance of the proposed scheme is demonstrated by some experimental results on real SAR images. In addition, we point out that the proposed scheme is also useful for other applications of image processing and analysis.