What is the purpose of RF coils?

The purpose of RF coils (radio frequency coils) is that they can be a transmitter, a receiver, or both. They are used in magnetic resonance imaging (MRI).


When an RF coil is used as a transmitter, it generates an an oscillating/rotating magnetic field. The static main magnetic field is perpendicular to it. It’s net alignment may be changed if the spin system receives energy. This energy is produced when the oscillation closely matches the natural precession of nuclear spins near the Larmor frequency.


When an RF coil is used as a receiver, it’s purpose is to detect the MR signal. The oscillating net magnetic flux from the excited spin system can be captured by the coil in which an induced electric current is generated. This current is then amplified, digitized, and filtered to extract frequency and phase information. Today RF receive-only coils are often collected into large arrays for use in parallel imaging applications.

Both (transmitter & receiver):

RF coils serving the functions of both transmitters and receiver were once the norm. However, today’s modern scanners mostly utilize separate transmit and receive systems. However, some special parts transmit-receive RF coils are still in common use, especially those used for head and knee imaging.

Where To Buy?

Click here to see our range of coils. Express Transformers and Controls Ltd are a trustworthy transformer manufacturer that offers you quality products with support at the price you can afford. Reap the benefits of quality transformers from us today!


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