Characterization of Current Equalizers for Coaxial Impedance Bridges

In this work, three passive and two active current equalizers designed for use in coaxial impedance bridges are characterized over a wide frequency range. A dedicated measurement circuit is used to determine the current mismatch between the inner and outer currents of the coaxial network. Active equalizers show a reduced current mismatch compared to passive equalizers. However, the resonance behavior measured at low frequency highlights the need for further optimization of active designs.