The NMR system is equipped with a room temperature transmitter coil and a receiver volume coil, the latter to be used as a reference.
Echoes were acquired by using both the double-D surface coil and the room temperature volume coil in order to compare their performances in terms of SNR.
The SNR is [approximately equal to] 182 for the double-D set-up and [approximately equal to] 776 for the volume coil set-up; the full-width-at-half-maximum values are 103 Hz and 96 Hz, respectively.
Finally, a TEM RF volume coil has been designed, built and tested for[sup.1]H MRI/MRS at 7T.
The third simulated model is a TEM volume coil for 7 T MRI.
Specifically, three coils which can be representative of different situations have been analyzed: a 1.5 T proton surface coil, a 7 T dual tuned surface coil and a 7 T proton volume coil.
The fixed capacitors can be seen joining the two halves of the volume coil. There is also a variable balancing capacitor on top of the volume coil.
Due to the large number and surface area of parallel conductors in a typical volume coil design, there is a degree of capacitive coupling from one part of the coil to the next.
Both homogeneous volume coils and inhomogeneous surface coils can be used for these purposes provided the appropriate RF pulses are used.
Zhang, "A dual-tuned quadrature volume coil with mixed [lambda]/2 and [lambda]/4 microstrip resonators for multinuclear MRSI at 7T," Magn.
Conventional volume coils, such as birdcage coils, are made up by the inductor and capacitor network unit cell assembled into a ring.
They cover surface coils, loop arrays, volume coils
, special purpose coils, coil interface circuits, coil modeling and evaluation, and radio frequency safety.