signals from undersampled data by lq minimization where 0< q≤ 1. We show that the null
space property (NSP)–a condition that is equivalent to exact recovery of any sparse signal
from its noiseless observation–is sufficient to stably and robustly recover any approximately
sparse signal via lq minimization. We further show that recovery of a signal via lq
minimization is robust with respect to perturbation of the measurement matrix. Finally, we …