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arXiv · 1904.07409

Complex Trainable ISTA for Linear and Nonlinear Inverse Problems

Satoshi Takabe·Tadashi Wadayama·Yonina C. Eldar
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Abstract

Complex-field signal recovery problems from noisy linear/nonlinear measurements appear in many areas of signal processing and wireless communications. In this paper, we propose a trainable iterative signal recovery algorithm named complex-field TISTA (C-TISTA) which treats complex-field nonlinear inverse problems. C-TISTA is based on the concept of deep unfolding and consists of a gradient descent step with the Wirtinger derivatives followed by a shrinkage step with a trainable complex-valued shrinkage function. Importantly, it contains a small number of trainable parameters so that its training process can be executed efficiently. Numerical results indicate that C-TISTA shows remarkable signal recovery performance compared with existing algorithms.

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Satoshi Takabe, Tadashi Wadayama, Yonina C. Eldar. 2019-04-16. Complex Trainable ISTA for Linear and Nonlinear Inverse Problems. https://arxiv.org/abs/1904.07409

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