A floating-point digital receiver for MRI

Author

Hoenninger, John C., III ; Crooks, Lawrence E. ; Arakawa, Mitsuaki

Author_Institution

RIL Div., Toshiba America MRI, Inc., San Francisco, CA, USA

Volume

49

Issue

7

fYear

2002

fDate

7/1/2002 12:00:00 AM

Firstpage

689

Lastpage

693

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 impulse response (FIR) filter coefficients provides fast switching between one of 129 different one-stage and two-stage multirate 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.

Keywords

FIR filters; biomedical MRI; biomedical electronics; low-pass filters; radio receivers; 4 to 125 kHz; MRI; RF receiver; analog-to-digital linearity; bandwidths; channel matching; clinical applications; commercial MRI system; dc offset; dual channel circuit board; fast switching; finite impulse response filter coefficients; floating-point digital receiver; large FIR low-pass filters; long word length; low latency; magnetic resonance imaging system; one-stage multirate FIR low-pass filter; preloaded table; signal fidelity; stability; two-stage multirate FIR low-pass filter; Bandwidth; Finite impulse response filter; Low pass filters; Magnetic fields; Magnetic resonance imaging; Magnetic separation; RF signals; Radio frequency; Radiofrequency amplifiers; Receiving antennas; Algorithms; Analog-Digital Conversion; Fourier Analysis; Humans; Magnetic Resonance Imaging; Radio Waves; Signal Processing, Computer-Assisted;

fLanguage

English

Journal_Title

Biomedical Engineering, IEEE Transactions on

Publisher

ieee

ISSN

0018-9294

Type

jour

DOI

10.1109/TBME.2002.1010852

Filename

1010852