Wolfgang Gaggl1, Andrzej Jesmanowicz1, Robert W. Prost1
1Biophysics, Medical College of Wisconsin, Milwaukee, WI, United States
Diffusion Tensor Imaging experiments require wide dynamic signal ranges, as they necessitate collecting an unweighted spin-echo image with a high intensity and a series of diffusion-weighted images with low intensities. Dynamic range increases with increasing the diffusion-weighting. Analog-digital converters with typical RF receivers have 16-bit resolution, while our system reaches over 20-bit. This is possible by direct-sampling the RF signal and downsampling it. Data from our receiver demonstrate superior signal-to-noise and diffusion-to-noise ratios and a dynamic range that is at least 4 bits wider than typical 16-bit receivers, shortening scanning durations and making it ideal for experiments with high diffusion-weighting.