An RF field pattern with improved B1 amplitude homogeneity

Zhiyue J. Wang, Dah Jyuu Wang

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Providing uniform RF excitation across the sample is challenging in building high-field human MRI scanners. The traditional design strategy for the RF power transmission has been trying to achieve a spatial distribution of B1 that is as uniform as possible in amplitude and direction. The fundamental limitation of this approach is that a constant solution of B 1 is not available from the Maxwell equations at radio frequencies. Here, a new design strategy is introduced that takes advantage of solutions of the Maxwell equations that have a B1 with uniform amplitude and varying direction in a lossless medium. In lossy media the B1 amplitude also varies in space, but there is no intrinsic penalty in the homogeneity due to increases of the real part of the wave vector at higher fields. We demonstrate how it might be realized for RF excitation through a computer simulation for a uniform medium.

Original languageEnglish (US)
Pages (from-to)1-5
Number of pages5
JournalConcepts in Magnetic Resonance Part B: Magnetic Resonance Engineering
Volume24
Issue number1
DOIs
StatePublished - Feb 2005

Fingerprint

Maxwell equations
homogeneity
Maxwell equation
Power transmission
Radio
Computer Simulation
Magnetic resonance imaging
lossy media
Spatial distribution
power transmission
penalties
scanners
excitation
radio frequencies
Computer simulation
spatial distribution
computerized simulation
Direction compound

Keywords

  • B amplitude
  • B field inhomogeneity
  • High-field MRI
  • RF excitation

ASJC Scopus subject areas

  • Chemistry(all)
  • Physical and Theoretical Chemistry
  • Spectroscopy

Cite this

An RF field pattern with improved B1 amplitude homogeneity. / Wang, Zhiyue J.; Wang, Dah Jyuu.

In: Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering, Vol. 24, No. 1, 02.2005, p. 1-5.

Research output: Contribution to journalArticle

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