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A floating-point digital receiver for MRI.

John C Hoenninger·Lawrence E Crooks·Mitsuaki Arakawa
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Abstract

A magnetic resonance imaging (MRI) system requires the highest possible signal fidelity and stability for clinical applications. Quadrature analog receivers have problems with channel matching, dc offset and analog-to-digital linearity. Fixed-point digital receivers (DRs) reduce all of these problems. We have demonstrated that a floating-point DR using large (order 124 to 512) FIR low-pass filters also overcomes these problems, automatically provides long word length and has low latency between signals. A preloaded table of finite impuls response (FIR) filter coefficients provides fast switching between one of 129 different one-stage and two-stage multrate FIR low-pass filters with bandwidths between 4 KHz and 125 KHz. This design has been implemented on a dual channel circuit board for a commercial MRI system.

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AlgorithmsAnalog-Digital ConversionFourier AnalysisHumansMagnetic Resonance ImagingRadio WavesSignal Processing, Computer-AssistedJournal Article

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BibTeXRIS

John C Hoenninger, Lawrence E Crooks, Mitsuaki Arakawa. 2002. A floating-point digital receiver for MRI.. https://doi.org/10.1109/tbme.2002.1010852

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