Signal processing in transceivers for nuclear magnetic resonance and imaging

The relationships between signal processing schemes and expected performances of several types of NMR transceiver are discussed to show how emerging digital technologies may be used in future systems. We identify a transceiver architecture where accuracy of the analog signal processing functions is not critical, and top performances are obtained through real-time digital signal processing. Our receiver, comprising an oversampling analog-to-digital converter scheme, achieves a dynamic range of 12 bits at bandwidths above 1 MHz, and a dynamic range in excess of 16 bits at bandwidths <15 kHz. We give an outline of specifications and hardware design issues of the main parts of this transceiver and demonstrate experimentally the superior performances of our receiver.