A NEW MICROSTRIP PICKUP COIL FOR THIN-FILM PERMEANCE METERS

In this paper we propose an application of microstrip line for a singl e-turn pickup Foil in the thin-film permeance meters. This coil has tw o electric ports with one terminated into 50 Ohm. It is free from LC r esonance up to a few GHz because the microstrip line does not resonate s and because the stray capacitance between the pickup coil and the dr iving sheets is small as compared with the conventional figure-8 coil. We measured the thin film permeance up to 700 MHz which is the upper frequency limit of the driving sheets used. The proposed coil has a po tential to measure thin-film permeances over the wide range from 1 MHz up to a few GHz.