2005/02/15 by Emmanuel Candes, Terence Tao, Candes, Emmanuel +1 · 45 citations
Computer Science · Mathematics · #94B05 #Cryptography and Security (cs.CR) #FOS: Computer and information sciences #FOS: Mathematics #Metric Geometry (math.MG) #cs.CR #math.MG #msc:94B05
paper · pdf · doi:10.48550/arxiv.math/0502327
22 pages, 4 figures, submitted
arxiv created 2005/02/15 · arxiv updated 2009/12/01
This paper considers the classical error correcting problem which is frequently discussed in coding theory. We wish to recover an input vector f ∈ \Rn from corrupted measurements y = A f + e. Here, A is an m by n (coding) matrix and e is an arbitrary and unknown vector of errors. Is it possible to recover f exactly from the data y? We prove that under suitable conditions on the coding matrix A, the input f is the unique solution to the ℓ1-minimization problem (‖x‖ℓ1 := ∑i |xi|) ming ∈ \Rn ‖ y - Ag ‖ℓ1 provided that the support of the vector of errors is not too large, ‖e‖ℓ0 := |\i : ei ≠ 0\| ≤ ρ⋅ m for some ρ> 0. In short, f can be recovered exactly by solving a simple convex optimization problem (which one can recast as a linear program). In addition, numerical experiments suggest that this recovery procedure works unreasonably well; f is recovered exactly even in situations where a significant fraction of the output is corrupted.