  The Cadzow's algorithm is a signal denoising and recovery method which was
designed for signals corresponding to low rank Hankel matrices. In this paper
we first introduce a Fast Cadzow's algorithm which is developed by
incorporating a novel subspace projection to reduce the high computational cost
of the SVD in the Cadzow's algorithm. Then a Gradient method and a Fast
Gradient method are proposed to address the non-decreasing MSE issue when
applying the Cadzow's or Fast Cadzow's algorithm for signal denoising.
Extensive empirical performance comparisons demonstrate that the proposed
algorithms can complete the denoising and recovery tasks more efficiently and
effectively.
