IEEE Transactions on Signal Processing
Decoding by linear programming
IEEE Transactions on Information Theory
Breaking the l1 recovery thresholds with reweighted l1 optimization
Allerton'09 Proceedings of the 47th annual Allerton conference on Communication, control, and computing
Modified-CS: modifying compressive sensing for problems with partially known support
IEEE Transactions on Signal Processing
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In this paper we study the compressed sensing problem of recovering a sparse signal from a system of underdetermined linear equations when we have prior information about the probability of each entry of the unknown signal being nonzero. In particular, we focus on a model where the entries of the unknown vector fall into two sets, each with a different probability of being nonzero. We propose a weighted l1 minimization recovery algorithm and analyze its performance using a Grassman angle approach. We compute explicitly the relationship between the system parameters (the weights, the number of measurements, the size of the two sets, the probabilities of being non-zero) so that an iid random Gaussian measurement matrix along with weighted l1 minimization recovers almost all such sparse signals with overwhelming probability as the problem dimension increases. This allows us to compute the optimal weights. We also provide simulations to demonstrate the advantages of the method over conventional l1 optimization.