Tunable and high directivity coupler for MRI applications

Sung Min Sohn, Anand Gopinath, John Thomas Vaughan

Research output: Chapter in Book/Report/Conference proceedingConference contribution

3 Citations (Scopus)

Abstract

This paper proposes a tunable and high directivity coupler that is used a RF power monitor in ultra-high field magnetic resonance imaging (MRI) systems. High directivity of a coupler is a critical factor to assure the accurate output in the reflected power measurement. To obtain a tunable and high directivity coupler, a novel directivity tuner includes tunable capacitors and resistors in a passive circuit. A well-tuned capacitance and resistance compensates phase difference and improves directivity in MRI operating frequencies. Therefore, this method significantly reduces the uncertainty of power measurement outputs and can accurately determine reflected power with load variation. The measured results of the proposed coupler agree with the simulation data and achieve excellent isolations (more than 65 dB) and directivities (more than 40 dB) in a compact size of 40 mm × 25 mm.

Original languageEnglish (US)
Title of host publication2014 IEEE MTT-S International Microwave Symposium, IMS 2014
PublisherInstitute of Electrical and Electronics Engineers Inc.
ISBN (Print)9781479938698
DOIs
StatePublished - Jan 1 2014
Externally publishedYes
Event2014 IEEE MTT-S International Microwave Symposium, IMS 2014 - Tampa, FL, United States
Duration: Jun 1 2014Jun 6 2014

Publication series

NameIEEE MTT-S International Microwave Symposium Digest
ISSN (Print)0149-645X

Other

Other2014 IEEE MTT-S International Microwave Symposium, IMS 2014
CountryUnited States
CityTampa, FL
Period6/1/146/6/14

Fingerprint

directivity
Magnetic resonance
couplers
magnetic resonance
Passive networks
Imaging techniques
Imaging systems
Resistors
Capacitors
Capacitance
output
data simulation
resistors
monitors
isolation
capacitors
capacitance
Uncertainty

Keywords

  • directional coupler
  • high directivity
  • magnetic resonance imaging (MRI)
  • power detection
  • Tunable coupler

ASJC Scopus subject areas

  • Radiation
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this

Sohn, S. M., Gopinath, A., & Vaughan, J. T. (2014). Tunable and high directivity coupler for MRI applications. In 2014 IEEE MTT-S International Microwave Symposium, IMS 2014 [6848491] (IEEE MTT-S International Microwave Symposium Digest). Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/MWSYM.2014.6848491

Tunable and high directivity coupler for MRI applications. / Sohn, Sung Min; Gopinath, Anand; Vaughan, John Thomas.

2014 IEEE MTT-S International Microwave Symposium, IMS 2014. Institute of Electrical and Electronics Engineers Inc., 2014. 6848491 (IEEE MTT-S International Microwave Symposium Digest).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Sohn, SM, Gopinath, A & Vaughan, JT 2014, Tunable and high directivity coupler for MRI applications. in 2014 IEEE MTT-S International Microwave Symposium, IMS 2014., 6848491, IEEE MTT-S International Microwave Symposium Digest, Institute of Electrical and Electronics Engineers Inc., 2014 IEEE MTT-S International Microwave Symposium, IMS 2014, Tampa, FL, United States, 6/1/14. https://doi.org/10.1109/MWSYM.2014.6848491
Sohn SM, Gopinath A, Vaughan JT. Tunable and high directivity coupler for MRI applications. In 2014 IEEE MTT-S International Microwave Symposium, IMS 2014. Institute of Electrical and Electronics Engineers Inc. 2014. 6848491. (IEEE MTT-S International Microwave Symposium Digest). https://doi.org/10.1109/MWSYM.2014.6848491
Sohn, Sung Min ; Gopinath, Anand ; Vaughan, John Thomas. / Tunable and high directivity coupler for MRI applications. 2014 IEEE MTT-S International Microwave Symposium, IMS 2014. Institute of Electrical and Electronics Engineers Inc., 2014. (IEEE MTT-S International Microwave Symposium Digest).
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