Performance of a petal resonator surface (PERES) coil via equivalent circuit simulation

Abstract

MRI coil parameters can be estimated via simulation using an equivalent RLC circuit to investigate coil performance. The Spice Opus simulator was used to simulate the loss return coefficients of a circular-shaped coil and a petal resonator surface (PERES) coil via equivalent (RLC) circuit. Simulated coefficient spectra were obtained and compared with experimentally-acquired spectra generated by both coils. From these spectra, resonant modes and quality factors of both coil prototypes were computed at 64 MHz and compared. Impedance and resonant frequency of the 8 petal-PERES coil design were computed and compared against those obtained with the circuit simulation. PERES coil design produced an impedance value of 54 $\Omega$, and an experimental resonant frequency differing by less than 1% from that predicted by the circuit simulator. The quality factor of the coil prototype differs by only 8% from that obtained with the simulation method. Due to construction imperfections in the coil design, it showed a drop of 8.84 dB in attenuation compared with the simulation results obtained with the aid of an equivalent circuit. This scheme may serve as an alternative to the trial-and-error method usually used to develop dedicated RF coils for magnetic resonance imaging.