A Nonconvex Approach for Exact and Efficient Multichannel Sparse Blind Deconvolution [article]

Qing Qu, Xiao Li, Zhihui Zhu
2020 arXiv   pre-print
We study the multi-channel sparse blind deconvolution (MCS-BD) problem, whose task is to simultaneously recover a kernel a and multiple sparse inputs {x_i}_i=1^p from their circulant convolution y_i = ax_i (i=1,...,p). We formulate the task as a nonconvex optimization problem over the sphere. Under mild statistical assumptions of the data, we prove that the vanilla Riemannian gradient descent (RGD) method, with random initializations, provably recovers both the kernel a and the signals
more » ... ^p up to a signed shift ambiguity. In comparison with state-of-the-art results, our work shows significant improvements in terms of sample complexity and computational efficiency. Our theoretical results are corroborated by numerical experiments, which demonstrate superior performance of the proposed approach over the previous methods on both synthetic and real datasets.
arXiv:1908.10776v3 fatcat:ku5mxr7ppfhejlh6kdyuuppspm