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IEEE Transactions on Antennas and Propagation
Volume 48 Number 3, March 2000

Table of Contents for this issue

Complete paper in PDF format

Ultimate Signal-to-Noise-Ratio of Surface and Body Antennas for Magnetic Resonance Imaging

Wilfried Schnell, Wolfgang Renz, Markus Vester and Helmut Ermert Senior Member, IEEE

Page 418.

Abstract:

Approximating the human body by a homogeneous half-space or cylinder the electromagnetic fields of surface antennas or wholebody antennas for magnetic resonance imaging (MRI) can analytically be calculated. Using these expressions the signal-to-noise ratio (SNR) of a general magnetic resonance detecting antenna can be predicted. We show how the optimum magnetic resonance antenna must look like to achieve the maximum SNR, which will also be presented. Finally,we apply the derived formulas to special antenna geometries like the single-and the double-loop coil, the magnetic dipole, and the"birdcage"resonator.

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