A new decoupling method for phased arrays in magnetic resonance imaging: an experimental approach

Li, B.K., Hui, H.T., Yang, C.H. and Crozier, S. (2008) A new decoupling method for phased arrays in magnetic resonance imaging: an experimental approach. Science Measurement and Technology, IET, 2 5: 317-325. doi:10.1049/iet-smt:20080033

Author Li, B.K.
Hui, H.T.
Yang, C.H.
Crozier, S.
Title A new decoupling method for phased arrays in magnetic resonance imaging: an experimental approach
Journal name Science Measurement and Technology, IET   Check publisher's open access policy
ISSN 1751-8822
Publication date 2008-09-01
Year available 2008
Sub-type Article (original research)
DOI 10.1049/iet-smt:20080033
Open Access Status
Volume 2
Issue 5
Start page 317
End page 325
Total pages 9
Editor M. Cunningham
Place of publication Stevenage, United Kingdom
Publisher The Institution of Engineering & Technology
Language eng
Subject C1
970109 Expanding Knowledge in Engineering
090399 Biomedical Engineering not elsewhere classified
Abstract A new decoupling method for magnetic resonance imaging (MRI) phased arrays is studied by experimental measurements. A laboratory measurement setup is built to characterise the signal coupling paths and their coupling strengths. A new concept, the receiving mutual impedance, is introduced to measure the coupled signals between the phased array elements. Measured values of the receiving mutual impedances for a typical two-element surface-coil array are obtained and used in other experiments to find the uncoupled voltages from the received voltages. Results show that the new decoupling method is both accurate and robust over a wide frequency range. Comparison of the uncoupled voltages with the actual ideal uncoupled voltages confirms that if the position of the signal source is known, almost error-free uncoupled voltages can be obtained. The errors resulted from a change of the position of the signal source are also measured and it is found that they generally increase with the deviation of the signal source from its position where the receiving mutual impedances are measured. The maximum % error of the uncoupled voltages is found to be below 10% when the signal source changes its position over a distance of half the length of a surface coil. Over this distance change, the signal isolation between the two surface coils is found to be at least 20 dB, whereas the maximum is more than 300 dB. The results demonstrate the effectiveness and the feasibility of the new decoupling method for use in MRI phased arrays.
Keyword Decoupling Method
MRI phased arrays
mutual impedance
magnetic resonance imaging
signal coupling paths
coupling strength
two-element surface-coil array
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: 2009 Higher Education Research Data Collection
School of Information Technology and Electrical Engineering Publications
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Citation counts: TR Web of Science Citation Count  Cited 3 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 4 times in Scopus Article | Citations
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Created: Wed, 15 Apr 2009, 21:56:51 EST by Ms Kimberley Nunes on behalf of School of Information Technol and Elec Engineering