Undersampling to acquire nuclear magnetic resonance images

In this paper, we present a method that permits the application of a direct digital receiver based on undersampling techniques to NMR and MRI scanners working with incoherent excitation pulses, and we evaluate the performance of such receivers in the acquisition and reconstruction of images. The method has been tested on a BRUKER BIOSPEC BMT 47/40, and the results show that undersampling can be used to process NMR and MRI signals, and that it correctly reconstructs images without loss of information, extending the range of applications of 'digital radio' techniques to NMR and MRI systems working with high-intensity magnetic fields. We also describe a series of tests performed to validate the application of undersampling to NMR systems and an algorithm to compensate the phase fluctuations due to the incoherent excitation pulses.