Nonlinear elastic wave spectroscopy combined with imaging techniques such as acoustic time reversal (NEWS-TR) or sparse array tomography is a promising new methodology for detecting microdamage at an early stage. When dealing with structures which could potentially contain many point-like nonlinear scatterers, there is a need to develop techniques for separately imaging the defects using a distributed sensor network which can be used either in time-reversal imaging processes or for tomographic imaging.. In this contribution, we discuss the application of Independent Component Analysis (ICA) methods to solve the problem of separating multiple nonlinear scatterers distributed throughout a sample, either by combining ICA with time reversal or by using ICA in conjunction with a tomographic experiment. We illustrate the procedure for ICA based tomographic imaging of multiple scatterers in an infinite medium.