New Schur-type-based PCI algorithms for reverberation suppression in active sonar

This paper presents two fast kinds of principal component inverse (PCI) algorithms using Schur-type subspace estimation methods for reverberation, especially for bottom reverberation suppression in active sonar. These algorithms apply Schur-type method into estimating and deleting the bottom reverberation echoes with a low rank. And the computational structure and complexity of Schur-type method are similar to that of LQ-decomposition except for the fact that plane and hyperbolic rotations are used. Compared with SVD-based PCI algorithm, these Schur-type-based algorithms have a similar estimation and separation for the reverberation subspace, but are more computationally efficient. In addition, because two Schur-type-based algorithms work column-wise, these are easy to be implemented in a real-time parallel DSP system.