A new calibration method for current probes

EMC engineers often use current probes to detect common mode currents. It is necessary to characterize the probes up to gigahertz frequencies. Existing calibration methods for current clamps suffer from the problem of not directly measuring the current within the current clamp. Instead, they either reconstruct the current from measurements at other locations or they use assumptions regarding the geometry which allows them to use a current that is measured at a different location without applying a mathematical correction. The proposed method overcomes these disadvantages by directly measuring the current at the center of the current clamp. The paper also discusses some of the non ideal effects of current clamps.