A NEW MINIATURE MAGNETIC-FIELD PROBE FOR MEASURING 3-DIMENSIONAL FIELDS IN PLANAR HIGH-FREQUENCY CIRCUITS

A new noncontacting miniature magnetic field probe for measuring the s urface current distribution on high-frequency planar circuits in x-, y -, z-directions in the 1-20 GHz band has been designed, fabricated and tested, The field probes have very small dimensions and do not need a ny connection to the operating circuit under test, therefore there is almost no perturbation of the circuit properties, This simple and prac tical magnetic field probes can be used to assist the design of microw ave circuits, antenna diagnostics and to test products in industry, Th is paper describes the producing procedure of the magnetic field probe s, a scanning diagnostic system, measurement examples and comparisons between measurements and calculations. The measurement results agree v ery well with theoretically expected field distributions.