A High Dynamic Range Receiver for Improved Diffusion Tensor Imaging

Wolfgang Gaggl¹, Andrzej Jesmanowicz¹, Robert W. Prost¹

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.