Compressed sensing (CS) studies the recovery of high dimensional signals from
their low dimensional linear measurements under a sparsity prior. This paper is
focused on the CS problem with quantized measurements. There have been research
results dealing with different scenarios including a single/multiple bits per
measurement, noiseless/noisy environment, and an unsaturated/saturated
quantizer. While the existing methods are only for one or more specific cases,
this paper presents a framework to unify all the above mentioned scenarios of
the quantized CS problem.
The phase transition is a performance measure of the sparsity-undersampling
tradeoff in compressed sensing (CS). This letter reports, for the first time,
the existence of an exact phase transition for the $\ell_1$ minimization
approach to the complex valued CS problem. This discovery is not only a
complementary result to the known phase transition of the real valued CS but
also shows considerable superiority of the phase transition of complex valued
CS over that of the real valued CS.
This paper is focused on solving the narrowband direction of arrival
estimation problem from a sparse signal reconstruction perspective. Existing
sparsity-based methods have shown advantages over conventional ones but exhibit
limitations in practical situations where the true directions are not in the
sampling grid. A so-called off-grid model is broached to reduce the modeling
error caused by the off-grid directions.