An automated measurement system for characterization of RF and gradient coil parameters

A fully automated laboratory-based measurement system for characterization of coil system parameters is presented. This method uses an inexpensive per sonal computer (PC)-controlled stepper motor positioning system in conjunct ion with a network/spectrum analyzer and an analog-to-digital converter (A/ D) board that allows high resolution data acquisition in an unattended mann er. A graphical interface was created for complete control of stepper motor movement, measurement, and data acquisition. The system is capable of perf orming a wide range of measurements that can, either individually or combin ed, characterize radiofrequency (RF) and gradient coils used in MRI, Measur ement methods, theory, and results for conductor and shield current distrib utions, mutual impedance, and magnetic fields are given. Comparisons with t heoretical calculations are included to validate the accuracy and utility o f the system.