Tuning and matching networks for MR imaging and spectroscopy

The authors briefly discuss four tuning and matching networks and their application range in magnetic resonance (MR) imaging and MR spectroscopy. Analytic expressions for the network elements needed to tune and match an MR imaging or spectroscopy probe for a given coil impedance are given, and the connection to the "standard" two-element capacitive matching networks is shown. The power loss factor and the phase shift between the input current and the load current are explicitly calculated for each of the four networks. The merits of the different matching networks are then discussed in the context of a general-purpose license plate coil commonly used in MR imaging.