In reading about magnetic resonance imaging, I was surprised to learn that the coil/antenna used to send a radiofrequency pulse into the person being scanned is not a coil/antenna at one end of the person, but a large coil actually wrapped around the person. I know how alternating current through a coil can generate EM radiation spreading outward from the coil, but how does a coil generate EM radiation ie. a radiofrequency pulse within the coil? Am I confused about some part of this? Thanks for your help.