Analysis of high-field RF coils using the method of lines

The method of lines is described as a novel and powerful way to analyze radio frequency (RF) coils for high-held magnetic resonance imaging. Originally developed for optical and microwave circuits, this method enables a full-wave solution to Maxwell's field equations without the computational burden of pure finite element or finite difference methods. Because only two of the three geometric dimensions are discretized, while seeking an analytic solution in the remaining space dimension, an efficient solution can be obtained at reasonable geometric restrictions. After outlining the theoretical formulation and the computer implementation of this technique, we will apply it to the modeling of microstrip RF transverse electromagnetic resonator coils at 200 and 400 MHz as well as a high-pass shielded birdcage resonator and a single-loop surface coil. With single-frequency solutions obtainable within 5-10 s on a personal computer, the approach proves highly suitable as a design tool and for rapid prototyping. (C) 2003 Wiley Periodicals, Inc.