Approximate message passing-based compressed sensing reconstruction with generalized elastic net prior

• We study compressed sensing when an initial estimation of the signal is available.
• We propose an approximate message passing (AMP)-based solution.
• Parameter selection, state evolution, and noise-sensitivity analysis are presented.
• A practical parameterless version of the proposed method is also developed.
• Simulation results demonstrate the efficiency of the proposed schemes.

In this paper, we study the compressed sensing reconstruction problem with generalized elastic net prior (GENP), where a sparse signal is sampled via a noisy underdetermined linear observation system, and an additional initial estimation of the signal (the GENP) is available during the reconstruction. We first incorporate the GENP into the LASSO and the approximate message passing (AMP) frameworks, denoted by GENP-LASSO and GENP-AMP respectively. We then focus on GENP-AMP and investigate its parameter selection, state evolution, and noise-sensitivity analysis. A practical parameterless version of the GENP-AMP is also developed, which does not need to know the sparsity of the unknown signal and the variance of the GENP. Simulation results with 1-D data and two different imaging applications are presented to demonstrate the efficiency of the proposed schemes.