20 June 2016

DIY radio frequency coils

Weiguo Li of the University of Illinois at Chicago learns to build an RF coil for his MRI experiments at the MagLab. Weiguo Li of the University of Illinois at Chicago learns to build an RF coil for his MRI experiments at the MagLab. Elizabeth Webb

This week at the lab, scientists from across North America are learning the theory and practice of radio frequency (RF) coils.

RF coils are used in magnetic resonance imaging (MRI) to transmit and receive RF signals. The MagLab’s Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) Facility at the University of Florida has an entire lab devoted to RF coil manufacture and development, led by RF engineer Malathy Elumalai.

In response to a growing need for visiting scientists to be able to troubleshoot and design their own RF coils, Elumalai is sharing her expertise at this week’s inaugural coil workshop. Empowering scientists to make their own coils makes sense. The demand for specialized coils has outpaced the rate at which Elumalai can design them. Additionally, sometimes the coils break, causing an experiment to come to a halt.

Throughout this week’s workshop, participants will learn the physics behind RF coils and be trained in specialized software for designing and modeling how the coils will behave under different magnetic fields and with different samples. Participants also have the chance to build their own coil and test it in the MagLab’s 4.7 tesla imaging magnet.

How do RF coils in MRI machines work? First, the coil transmits an RF signal, which produces a magnetic field perpendicular to the one already being produced by the magnet. Then, the same RF coil (or a separate one) receives signals indicating how the nuclear spins inside the subject are relaxing. This information is then processed as an image. Without RF coils, there’d be no "I" (imaging) in MRI!

The workshop is an example of the ongoing training we offer our "users" so that they can make the most of their time with our magnets. The MagLab also offers a User Summer School and a Theory Winter School once a year.


Text and image by Elizabeth Webb.

Last modified on 20 June 2016