Approximate message-passing with spatially coupled structured operators, with applications to compressed sensing and sparse superposition codes
نویسندگان
چکیده
We study a compressed sensing solver called Approximate Message-Passing when the i.i.d matrices —for which it has been designed— are replaced by structured operators allowing computationally fast matrix multiplications. We show empirically that after proper randomization, the underlying structure of the operators does not significantly affect the performances of the solver. In particular, for some specially designed ”spatially coupled” operators, this allows a computationally fast and memory efficient reconstruction in compressed sensing up to the information theoretical limit.
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