Analysis of the ratio of ℓ1 and ℓ2 norms in compressed sensing
Analysis of the ratio of ℓ1 and ℓ2 norms in compressed sensing
复制标题
压缩感知中≤1范数与≤2范数的比值分析
DOI:
10.1016/j.acha.2021.06.006
复制
发表时间:
2021
影响因子:
2.5
通讯作者:
Webster, Clayton G.
中科院分区:
文献类型:
--
作者:
Xu, Yiming;Narayan, Akil;Tran, Hoang;Webster, Clayton G.
We study the ratio of ℓ 1 and ℓ 2 norms (ℓ 1/ℓ 2) as a sparsity-promoting objective in compressed sensing. We first propose a novel criterion that guarantees that an s-sparse signal is the local minimizer of the ℓ 1/ℓ 2 objective; our criterion is interpretable and useful in practice. We also give the first uniform recovery condition using a geometric characterization of the null space of the measurement matrix, and show that this condition is satisfied for a class of random matrices. We also present analysis on the robustness of the procedure when noise pollutes data. Numerical experiments are provided that compare ℓ 1/ℓ 2 with some other popular non-convex methods in compressed sensing. Finally, we propose a novel initialization approach to accelerate the numerical optimization procedure. We call this initialization approach support selection, and we demonstrate that it empirically improves the performance of existing ℓ 1/ℓ 2 algorithms.