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Magnetic field visualisation and inductance calculation of a simple configuration surface coil at low magnetic field

 

A.O. Rodríguez*^a, R. Amador**^a, R. Rojas^b, F.A. Barrios^c

 

^a Centro de Investigación en Imagenología e Instrumentación Médica, Universidad Autónoma Metropolitana Iztapalapa, Av. San Rafael Atlixco 186, México, D.F., 09340. México.

^b Louisiana State University, Health Science Center, School of Medicine, Department of Radiology, 1542 Tulane Ave., Room 308, New Orleans, LA 70112, USA.

^c Instituto de Neurobiología, UNAM-Juriquilla, Juriquilla 76230, Querétaro, México.

 

* Corresponding author:
Alfredo O. Rodríguez,
Centro de Investigación en Imagenología e Instrumentación Médica,
Universidad Autónoma Metropolitana Iztapalapa,
Av. San Rafael Atlixco 186, México, D. F., 09340. México.
Telephone No.: (5255) 85024569, Fax No.: (5255) 804-4631,
e-mail: arog@xanum.uam.mx.

** Present Address:
Institute of Imaging Science,
Vanderbilt University,
Nashville TN 37232-2675, USA.

 

Recibido el 28 de enero de 2004;
Aceptado el 30 de marzo de 2005.

 

Abstract

We propose a simple method based on the quasi-static approach to visualise the magnetic field created by a simple configuration coil using the calculation for coil inductance. Faraday's law was used to calculate the inductance value and to simulate the magnetic field produced by circular-shaped and square-shaped coils. A software tool was developed to compute the coil inductance, and display the simulated magnetic field. We compared the predicted measured values of inductance, and performed a comparison plot of area versus inductance for both coils. Three dimensional plots of simulated fields are also shown. A circular-shaped coil was built using the method reported here, and brain images were acquired. This approach proved to be useful as an aid to visualise the magnetic field generated by simple coil geometries, and, simultaneously, calculate their coil inductance values.

Keywords: Inductance; RF coil; simulation; magnetic field visualisation; magnetic resonance imaging; brain.

 

Resumen

Un método simple basado en el enfoque cuasiestático se propone para visualizar el campo magnético creado por una antena, a través del cálculo de la inductancia de la antena. La ley de Faraday se emplea para calcular el valor de la inductancia y simular el campo producido por una antena circular y una antena cuadrada. Una herramienta software se desarrolló para obtener la inductancia de la antena y visualizar su campo magnético. Comparamos los valores experimentales y teóricos de la inductancia, graficamos el área de la antena versus la inductancia para ambos geometrías. Se obtuvieron gráficas tridimensionales para mostrar la simulación del campo magnético. Construimos una antena circular basada en este método para generar imágenes cerebrales. Este método muestra que es posible calcular la inductancia y visualizar el campo magnético de antenas RF con geometrías simples.

Descriptores: Inductancia; antena RF; simulación; visualización campo magnético; imagenología por resonancia magnética; cerebro.

 

PACS: 42.30.Va; 76.60.Lz; 76.60.Pc; 87.57.-s; 87.61.-c; 87.61.Cd; 87.63.-d.

 

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